ChemSemBlog

The Preparation of Highly Conjugated Compounds for Device Applications and the Preparations of Functional Sol-gels for Control of Cell Growth.

by Celena on Mar.15, 2010, under ChemSem 08, _Spring 2010

This week’s presenter Elizabeth M. Sanford spoke of two topics: one dealing with the preparation of highly conjugated compounds as well as the functional of sol-gels for the control of cell growth. Sanford graduated with a BA in Chemistry from Smith College and her current research focuses on the development of new materials for applications in electronics and the biomedical sciences. Sanford’s presentation was very understandable and she explained the topic very well making eye contact with the audience and being enthusiastic about the topics.

Polyphenylene vinylene (PPV) is a conducting polymer that has been successfully processed into a highly ordered crystalline thin film. It’s prepared by thermal processing of a precursor polymer and it has been found to be capable of electroluminescence. When doing studies of this polymer they found using a photovoltaic solar cell that when electrical energy is inputted then light energy is outputted making it a electroluminescent device. Sanford then told us of organic light emitting diols made of polymers that are present in television sets and watches. These diols would be perfect if someone wanted to have a computer screen in the visor of the helmet or a TV screen that would be able to roll up into the ceiling. In her study she first wanted to solvate electrolytes using a substance that was polar to separate from the non-polar regions. They found that if the polymers were covalently linked they would group together. The proposed polymers consisted of homopolymers and alternating polymer backbones. This process uses organic chemistry the Witting reaction and the Gilch reaction.

In using polymers they would try to cleave off the side chains with halomethylation but the product wouldn’t be pure. The Gilch reaction would produce a gelatin product that left intractable material and had varying molecular weights. Due to these problems her research group decided to switch to smaller molecules, exploring with thiophene compounds as core molecules. She then used biothiophene and performed a coupling reaction with palladium, then continued on to perform the witting reaction. There were still some solubility problems encountered due to connecting the aromatic rings together but they tried putting ethers, alkyl groups, and branching alkyl groups on the molecules to aid in a better connection of the aromatic rings. Their future plans are to characterize polymers and prepare and testing devices.

For the second part of the presentation Sanford spoke of the preparation of functional sol-gels. There are many synthetic blood vessels and tissue culture making support for cells, this group wanted to functionalize glass to see if they could get cells to grow. They also wanted to avoid the synthetic costs so they performed this research in-house using sol-gels to make glass at a low temperature. They first took tetraethyl orthoscilicate, hydrolyzed it, condensed it and ended up forming glass. Some problems that were encountered were the forming of the glass was too quick and it would form inside the glass ware that they were already using it, and it couldn’t be coated. To solve this problem they purchased a hobby lobby airbrush from Aldrich and were able to spray coat the glass. When cells were put on glass cultures they didn’t really like to grow, instead they would grow on top of one another until eventually they died. When cells were put on aminopropyl treated sol-gels they spread out and grew very well. They find the applications to this study to aid in cell growth test strips, finding out what would be the best growth treatment and cell growth into packaging materials of bone. In the future they wish to try more substrates, different starting techniques, and characterize surfaces.

Many students seemed to be engaged by this presentation and asked many questions. Sanford was able to answer them well and encouraged me to learn more or do summer research on these subjects. Sanford spoke of her school of graduate studies a little, but I wasn’t really encouraged to attend. This topic was interesting I learned a lot of new things.

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Review of Elizabeth M. Sanford’s The Preparation of Highly Conjugated Compounds for Device Applications and the Preparation of Functional Sol-Gels for Control of Cell Growth

by shieun on Mar.14, 2010, under ChemSem 08, _Spring 2010

I’m sure that for most of the students, chemistry seminar is their last course to attend before heading off for spring break. So, it would be natural for the atmosphere to be distracted and antsy. However, our speaker Elizabeth M. Sanford was able to catch my attention and keep me interested in her presentation. An associate professor at Hope College in nearby Holland, MI, Sanford seemed both an impressive researcher and teacher.

She heads over two research projects currently: highly conjugated compounds and functional Sol-Gels for cell growth. The highly conjugated compounds have electroluminescent properties that basically do the opposite transition of energy of a solar cell. They are also thin and flexible and can be used in lighting fixtures, monitors and screens. Some awesome examples Sanford gave us were: screens inside helmets for military personnel, a television screen that can be rolled up like a projector screen, more natural indoor lighting, or plastic that glows in the dark. However, these products have short lifespan due to the phase separation issue from mixing polar and nonpolar reagents. Sanford tried to solve this issue by adding polar groups on conjugated compounds. However they team ran into a dead end when they could not elicit the amount of control they needed to synthesize the polymer.

Her second research deals with Sol-Gels. Tissue culture requires special petri dishes and special formulas which all add up to a financial burden. Unfortunately regular glass deters the growth of such cells. Frustrated by the way other people were going around trying to solve this problem, Sanford decided to solve it herself. Sanford proposed to attach functional ends to the glass through coating or dipping. While the glass was made quite easily, the coating and dipping caused the most trouble. However, from a glass company working friend, Sanford learned that they favoured spraying the glass. So she found a relatively cheap method instead. An airbrush from Hobby Lobby provided the answer.

One of the aspects that made her presentation engaging was that she made a connection with her audience; her family often accidently exit into Berrien Springs on their way home and she commented on Kozy’s Chicken, a local restaurant’s giant plastic mascot. Her acknowledgements are notably more detailed than other presenters, not due to the number of people to thank but because she seems to genuinely know what they did and what they are doing and found it interesting enough to tell us. Even more exceptional was her small bit on Hope College’s missionaries, and it was refreshing to meet a presenter who did both research and academic work as well as missionary work.

Her slides were very simple, almost bare of any affectation, mostly black and white reactions and text. However, the pictures that she had were more than interesting, because who doesn’t want to look at the coolest new gadgetry and technological advances that look more science-fiction than reality.

Laymen’s Summary of Chemistry Seminar: Highly conjugated polymers do something cool. They take electricity and turn it into light, the exact opposite of solar cells that use the energy of sunlight and turn it into electrical energy. Although they have been making progress, Sanford’s team went back to the beginning to mess around with different cores. Tissues cannot be made without really special equipment, but Sanford found that glass with functional groups attached to it works almost as well as those special petri dishes.

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The Preparation of Highly conjugated compounds for device applications and the preparation of functional sol-gels for control of cell growth

by Andrew Yang on Mar.14, 2010, under ChemSem 08, _Spring 2010

This week’s presentation (3-11-2010) was titled “The Preparation of Highly Conjugated Compounds for Device Applications and the Preparation of Functional Sol-Gels for Control of Cell Growth” and was presented by Elizabeth M. Sanford from Hope College in Holland, Michigan. As you can see from the title, her presentation was a two part presentation that dealt with Highly Conjugated Compounds, and Sol-Gels for Cell Growth.

Highly Conjugated Compounds are used as electroluminescent devices to get light. It is used for modern TVs, the best example being Sony’s new line of TVs. The only problem with this new technology is that it has a short life, Sony’s TVs lasting only about five years. In order to synthesize these molecules, general organic chemistry reactions are used. These reactions include, Halogenation, Acid workup, Williamson ether synthesis, and other ether synthesis. By increasing conjugation, they are able to get more luminescent characteristics. After polymerization, the product precipitates out, forming a red compound that looks like an artificial liver.

Sol-Gels are used for two procedures: Making synthetic tissue from individual’s own cells, or using a matrix for the support of tissue such as bone. This is done by packing the bone with this matrix, and allowing the bone to grow. This matrix however, must be made of material that cells like to attach to. It needs to be a material that the body will accept and not reject. Another issue with this research is that the tissue culture is expensive. Elizabeth Sanford however invented a spraying device, which allows people to find what material is best for cell growth with lower cost.

Overall, I thought her presentation was interesting, and clearly presented. I would love to hear more about her progress later on.

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A New Growing Surface

by ckrym on Mar.12, 2010, under ChemSem 08, _Spring 2010

Elizabeth M. Sanford from Hope College presented at Chemistry Seminar March 11, 2010. The presentation was divided into two parts. If I were to describe this presentation to a family member or friend I would say that it describes making synthetic organic compounds and creating glass that can grow cells for microbiology. The first was entitled “Preparation of highly conjugated compound for device application” and described using Gilch polymerization and the Wittig reaction to produce synthetic organic material made of thiophenes.

The second half of the presentation was entitled “Preparation of function sol-gels for control of cell growth”. This part of the presentation interested me the most and it dealt with biological techniques to use synthetic materials in the body. Sanford pointed out that researchers either want cells to grow in the case of tissue, bone, or blood vessel implants or do not want cells to grow in the case of stints. To prevent cells from growing stints are coated in aspirin compounds, or anti-cancer type agents that cause cell proliferation. Sanford’s research team attempted to make cells grow on glass using sol-gel. The sol-gel is created at low temperatures using tetraethyl orthosilicate with aminopropyl additives. The sol-gel hardens very quickly and spin-coating and dip-coating failed to after dilution the gel is sprayed on with an air bush. The treated glass allows cell growth unlike normal class dishes. Possible applications for this technology are medium test strips for microbiology with several different additives in strips on one plate and also to improve cell growth in products that contain glass used as packing in the body.

This presentation was easy to follow. Sanford did a great job of combining the practical purpose of her research with detailed methodology.

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New Materials for Electronics and Biology

by kgardner on Mar.12, 2010, under ChemSem 08, _Spring 2010

Dr. Elizabeth Sanford came to Andrews to talk with us about “The Preparation of Highly Conjugated Compounds for Device Applications and The Preparation of Functional Sol-Gels for control of Cell Growth”. Dr. Sanford was very interesting to listen to as she talked about the research going on in her lab. She has been focusing in two different areas, the first on being conductive polymers. She began this part of her talk with showing us some of the more resent discoveries and products, but mentioned that some of these had been seen in the 1950’s. Organic light emitting diodes can be found at this time in cameras, cell phones, and portable displays, among other things. The specific type that Dr. Sanford has been working with in her lab has been with light emitting electrochemical cells.

The other subject that Dr. Sanford talked about was her sol-gel experiments. The need to increase cell growth and decrease cell growth in different areas was discussed, she then moved on to some examples of each. For instance when bone needs to be replaced, they want to make sure that cells from the body will grow on it and it will be like other bone. However, an example of when they do not want a lot of cell aggregation and growth is when they put a shunt into a blood vessel. Dr. Sanford’s research deals with making sol-gels as an alternative in ex-vivo cell growth to glass. Cells do not grow well on glass so she has been working on plating Petri dishes with her sol-gels to make a better growth environment for cells.

All together it was a very educational seminar and we learned a lot. I would describe it to a non-science friend as first having to do with making objects that glow, and then creating a material to grow cells on.

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March 11 Seminar

by fletchek on Mar.12, 2010, under ChemSem 08, _Spring 2010

This week’s speaker was Elizabeth Sanford from Hope College.  She talked about two of her research projects.  The first project was based on conductive polymers.  The first conductive polymer was discovered by Heeger, Diarmid, and Shirakawa, and they received a Nobel Prize for it.  Sanford’s project focused on polyarylenevinylenes.  They are just semiconductors, yet they have electroluminescent properties (in other words, they glow).  Glowing plastics have great potential.  The organic light emitting diodes have already been commercialized in small devices such as cell phones, but due to a short lifetime have yet to be incorporated into large devices.  Sanford used two different reactions to make the polymers.  The first reaction was the Gilch route, the second reaction was the Wittig synthesis.  The Gilch method gave a 20-30% yield using anhydrous solvent.  The product was intractable (didn’t dissolve in anything) and looked like “chopped liver” on the GC-MS.  The Wittig synthesis gave a much better yield, 40-80%.  The product had a lower molecular weight, increasing its solubility.

Sanford’s second project was using sol-like gels to mediate cell growth.  Sanford took on this project because she discovered that no one had a rational approach to making biological polymers.  There are already synthetic blood vessels used for kidney dialysis, and stents used for clearing blocked arteries.  The problem with stents is that the body has an immune response to them.  The infection fighting cells travel to the artery and clog it up again.  But, if stents could be coated to prevent or reduce an immune response, it would be a great help.  This is where sol gels come in.  If glass could be functionalized with sol gels, cell growth could be adjusted on it.  This would reduce the need to buy expensive cell culturing equipment.  First, the glass itself has to be made.  At first, the glass formed too quickly to coat it with the sol gel.  Spin and dip coating also failed.  But, an airbrush from Hobby Lobby was finally used to get the job done.  With the sol gel technique, one could have a glass slide painted with many different functionalities.  Several different groups could be tested at once.  The glass staining techniques need to be improved, however.

The conductive polymer project had a sequence of organic reactions that I had trouble following, so I wasn’t too interested in that.  However, I found the sol gel project to be very interesting.  I’ve been told that “plastics make it possible,” but now it seems that it’s glass that’s making it possible to grow cells.  I would like to know which kind of cells Sanford plans to investigate with the sol gels.  I would also like to know how large the functionalized glass slides can get.  I had never heard of synthetic blood vessels and stents before, so this talk introduced me to them.  Finally, I learned that there are some synthetic organic chemists that like to shop at Hobby Lobby.  In summary, the first project of this presentation dealt with organic polymers that conduct electricity; the second project dealt with growing cells on glass.

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Synthesis, Applications, and Commercial Development of Dendrimers

by Danuel on Mar.09, 2010, under ChemSem 07, _Spring 2010

Chemistry seminar on March 4th, 2010 was presented by Joseph Heinzelmann. He is a product manager for Dendritic Nanotechnologies Inc. I would describe this seminar as a description of the applications of new polymers called dendrimers, and new insight into the use of a chemistry degree. The presentation consisted of two parts. The first described dendrimers.  The second part of the presentation focused on the use of a chemistry or biochemistry degree.

Nomenclature or dendrimers begins with branching then the surface groups. Dendrimers were found to be 1-10nm in diameter, built using organic chemistry, and consisted of branching which aided in the growth of functional groups on the outside. They were also found to be cross linkers interacting with other polymers, gaining strength and losing flexibility, allowing protein and antibodies to line up, making it easy to detect where a heart attack was taking place. Dendrimers also help create osmotic pressure of a molecule without losing it through a membrane. An interesting part of their structure is a void space which allows for carrying molecules such as drugs. This capacity can make them useful in targeting cancer cells. Heinzelmann has an idea that the ligands could be targeting groups, and the drugs used in cancer treatments could be inserted in these void spaces, then the dendrimer could be directed to the area of cancer cells, centering the drugs on them, killing them. Another idea is that the dendrimers can be modified to carry a genetic code involving siRNA-small interfering RNA.

Heinzelmann then focused on the career possibilities for chemistry majors, aside from the usual route undergrads take. Himself only obtaining a Bachelors in Chemistry, Heinzelmann stressed that it was not necessary to earn a PhD in science to achieve a fulfilling career life in chemistry. In the business world, there is a need for marketing, supply chain management, sales, and regulatory positions with the government. An open mind keen on learning proved to be a key factor in success.

Though there was some lack of fully defined explanations on several things, Heinzelmann did have all the data required to make a clear case for the DNT product value and progress. Furthermore, Heinzelmann understood the material he was discussing and answered the questions that were asked clearly and with specific and useful responses. Overall the lecture was well presented, and put together.

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Synthesis Application and Commercial Development of Dendrimers

by brummett on Mar.09, 2010, under ChemSem 07, _Spring 2010

Joseph Heinzelmann visited us from Mount Pleasant, Michigan from Dendritic Nanotechnologies, DNT.  At Dendritic Nanotechnologies Joseph Heinzelmann is a product manager.  Joseph in in his sixth year of experience experience at DNT, these experiences include production Dendrimers, Business Development and Production Management.  Joseph has played a very important role to continual development of the PAMAM and PRIOSTAR production lines at DNT.  Joe received a BS degree in chemistyr from Albion College in Albion Michigan in 2004 and then received an MBA in 2009 from Northwood University.  Joe is a happily married man with a two year old daughter.

Joseph Heinzelmann’s work with DNT is solely focused on Dendrimer production.  There are two classes of dendrimers, the Priostar and the PAMAM.  The PAMAM is the dendrimer that Joseph spoke with us about on thursday. A major question is what is a dendrimer.  A dendrimer is carefully architected and highly organized.  Dendrimers are very limited in there size.  They tend to range in size from 1-10 nanometers.  These dendrimers are built via organic chemistry.  These dendrimers can be created to be larger in size and density.  However, the higher the density the more brittle it makes the product.  These dendrimers are being used to create a type of cancer killing drug carrier.  Meaning that the dendrimer is like a capsule that will carry the cancer killing drug around the body and then with ligands being attached to the exterior of the dendrimer, allowing the cancer cells to be targeted.  This study and development is key because this could lead to a cancer cure.  The cancer killing drug would be placed within the void space in the generation 4 to generation 6 dendrimers.  However, as feasible this idea is it will not be available to the market for some time due to a lack of research in the field and funding from the government to continue to studying.

Joseph Heinzelmann was a great speaker.  He spoke loudly and clearly and was very energetic and knowledgeable about the topic he presented.  Due to a lack of time I was not able to ask all of my questions about the dendrimers.  I would really like to know if dendrimer is cancer specific?  How feasible will it be to get these dendrimers to have the cancer killing drug attached to the dendrimer?

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Synthesis , Applications and Commercial Development of Dendrimers

by seonui on Mar.08, 2010, under ChemSem 07, _Spring 2010

The speaker of Chemistry Seminar held in March 4, 2010 was Joseph Heinzelmann, who has 6 years of experience at Dendrictic Nanotechnologies (DNT). As a product manager, he has worked for business and development of Priostar and PAMAM dendrimers at his company. So, during his seminar he emphasized the importance of marketing and business in chemical industry. The chemical industry has shown rapid growth, and the U.S. chemical output is $400 billion a year.

In addition, through his presentation, I could learn more about dendrimers. DNT produces two product lines of dendrimers, Priostar and PAMAM, and both dendrimers have endless possibility. Dendrimers are highly branched polymer molecules consisting of core molecules, branch structures usually until fifth generation, and surface groups of several kinds of ions. The surface of dendrimers can be modified, and void space between generation structures is capable of carrying molecues like drugs or imaging agents. Therefore dendrimers can cover a very wide range of application area including druge delivery, siRNA and DNA transfection vectors, surface modifier for conjugating antibodies, peptides, or dyes, and so on.

In spite of these a lot of advantages, in fact, dendrimers are not yet used in therapeutics as drug carriers for treatment of cancer. There are several significant problems that need to be solved. At first, researchers face manufacturing problem, and the safety of dendrimer is required to be studied before dendrimers are used to cure cancer. In addition, drug delivery takes a long time and a lot of money.

To my non-science friends, I would say that dendrimer is a highly branched spheroid or globular molecules that have a lot of applications in life sciences research, industrial, and pharmaceutical areas.

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Synthesis, Applications, and Commercial Development of Dendrimers

by Celena on Mar.07, 2010, under ChemSem 07, _Spring 2010

The presenter for this week was Joseph Heinzelmann. He completed his Bachelor’s of Science in Chemistry and began working at Dendritic Nanotechnologies (DNT). Heinzelmann is currently a DNT products manager, whose main focus of research is PAMAM dendrimers. A dendrimer is a highly organized polymer built from repeating branching made in order of molecular complexity. PAMAM dendrimers represent an exciting new class of macromolecular architecture called “dense star” polymers. Dendrimers have a high degree of molecular uniformity, narrow molecular weight distribution, specific size and shape characteristics, and a highly- functionalized terminal surface. The manufacturing process is a series of repetitive steps starting with a central initiator core. Each subsequent growth step represents a new “generation” of polymer with a larger molecular diameter, twice the number of reactive surface sites, and approximately double the molecular weight of the preceding generation.

Nomenclature or dendrimers begins with branching then the surface groups. Dendrimers were found to be 1-10nm in diameter, built using organic chemistry, and consisted of branching which aided in the growth of functional groups on the outside. They were also found to be cross linkers interacting with other polymers, gaining strength and losing flexibility, allowing protein and antibodies to line up, making it easy to detect where a heart attack was taking place. Dendrimers also help create osmotic pressure of a molecule without losing it through a membrane. An interesting part of their structure is a void space which allows for carrying molecules such as drugs. This capacity can make them useful in targeting cancer cells. Heinzelmann has an idea that the ligands could be targeting groups, and the drugs used in cancer treatments could be inserted in these void spaces, then the dendrimer could be directed to the area of cancer cells, centering the drugs on them, killing them. Another idea is that the dendrimers can be modified to carry a genetic code involving siRNA-small interfering RNA.

With all of these plans for dendrimers there is the problem of manufacturing. They must be taken through a regulatory process, get FDA approved, solve safety issues, and the drug delivery takes time. Purity has also been an issue, the dendrimers cannot touch each other or they will create dimmers. One must also use large excess of reactant about 100 equivalents per surface. Heinzelmann then concluded that PAMAM dendrimers have great promise, endless possibilities, trouble securing funding, and the manufacturing process must be improved and that there are still new classes of polymers still being developed. He also gave very useful information about the future careers awaiting chemistry majors and believes that one must stay open minded and keep learning.

During this presentation Heinzelmann’s audio was well, made eye contact with the audience, went through the slides quickly and finished on time. I found this topic to be very interesting and many students seemed to be engaged. There were many questions answered at the end and all of these questions were answered well. This presentation did encourage me to learn more about PAMAM dendrimers and I wouldn’t mind doing summer research on this topic. I wasn’t really encouraged to go to the speaker’s school for graduate studies, but Heinzlemann didn’t really speak about it, but he was available to answer question if one was to ask at the end of the presentation.

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Dendrimer

by young on Mar.07, 2010, under ChemSem 07, _Spring 2010

There was a presentation on March 4, 2010 about synthesis, application and commercial development of dendrimer. The presentation was given by Mr. Joseph Heinzelmann who is the product manager of dendritic nanotechnologies, Inc. The presentation was very impressive because it was full of informative contents about business in chemistry as well as scientific contents. He started the seminar introducing the basic knowledge of dendrimers. What properties do dendrimers have? How are they synthesized? What application can they be used?

Mr. Joseph Heinzelmann told us that dendrimers are highly organized polymers which are built from repeating branching sides. As the complexity of the molecules, there are a number of different types. Dendrimer is composed of a core molecules, interior rod, and surface group. The question I asked to him was that which molecules can be a core molecule. He answered that any molecule is able to be a core molecule of a dendrimer and the company he is working for is using ammonia group for the core molecule. One of the applications of the dendrimer is to carry molecule like drugs or imaging agents. Nowadays, the treatment for cancer is MTX which blocks the pathway of synthesizing Tetrahydrofolate from Folate. However, the weak point of MTX is that it is non-selective. It means that MTX also affect on normal body cells which grow rapidly such as hair cell. If dendrimers carry MTX to only tumor cells, they will be the best way to treat cancer.

I would tell my friends that the presentation was a good chance to learn how a company based on chemistry is operated and how dendrimers can be used.

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The Business of Dendrimers

by ckrym on Mar.07, 2010, under ChemSem 07, _Spring 2010

Chemistry seminar on March fourth was presented by Joseph Heinzelmann. He is a product manager for Dendritic Nanotechnologies Inc. I would describe this seminar to friends and family as a description of the applications of new polymers called dendrimers, and new insight into the use of a chemistry degree. The presentation consisted of two parts. The first described dendrimers and a new type of PAMAM dendrimer. The second part of the presentation focused on the use of a chemistry or biochemistry degree.

A PAMAM dendrimer is an acronym for a polyaminoamine dendrimer. These are a new class of polymers being developed that begin with a bi-functional core molecule. It is hoped that dendrimers will be used in cancers treatment as they can carry ligands that locate cancer on their surface and deliver drugs to kill the cancer from the void of the dendrimer. One complication with these polymers is that they cannot touch or they become dimers. A great deal of excess reagent must be used to prevent this from happening. I asked if further research was being done to reduce the waste of reagent. Heinzelmann informed me that they are looking at covering the active groups that cause the dendrimers to combine.

The presentation helped to bring some new ideas to us about what can be done with a chemistry or biochemistry degree. Often we assume that we will all either go into some kind of medical field or get a doctoral degree and focus on research. This presentation helped to remind me that there are a lot of other options for students getting chemistry degrees. Heinzelmann mentioned that in the drug and chemical industry there are jobs like sales, and product managing. He also suggested some professions I would not associate with chemistry majors. The main one that surprised me was getting a Juris Doctor, JD, to go into patent law. I currently have quite a few friends who are pre-law and all of them are English or political science majors.  I am personally not interesting in using my biochemistry degree to get a JD, but it’s always good to be informed of carrier choices I wouldn’t necessarily have thought about.

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Chemistry from the Business side

by shulla on Mar.07, 2010, under ChemSem 07, _Spring 2010

This week Joseph Heinzelmann of Dendritic Nanotechnologies (DNT) lectured for ChemSem. Though not involved as deeply in chemistry as the common speakers, he did explain the chemistry that DNT is researching and to what end. Specifically, DNT is endeavoring to grow fractal dendritic polymers which, as a course of steric inhibition eventually resemble spheres, could be used in a number of applications.

To grow these symmetrical dendrimers, DNT started with a form which came to be called Prioster. It seems, though not clearly explained, that Prioster offered significant challenges on a synthesis and purification front causing DNT to pursue other options in research in this field. The next stage involved poly-amino-amine dendrimers (Pamams) which thus far appear to be far more promising. Though only a small amount was described concerning the actual production of Pamams, much was described concerning their effect, especially their potentials as pharmaceutical transportation mechanisms in the body. The dendrimers conform to spheres after enough branching has taken place (4-10 generations) but there are still vacancies inside the structure where other molecules can be held. In terms of cancer research, by tagging the dendrimer in such a way as to cause it to dissolve under the right biological conditions, it is possible to cause the drug to be released in small but potent quantities at a very targeted point, i.e. a cancerous cell.

There were several questions I had regarding a number of applications of DNT products. First of all, considering the small size of the spherical 4th generation dendrimer, how hardy is the shape? Does the dendrimer form a solid useful sphere and therefore could it be used as a nanotechnology ball bearing? Furthermore, what is the robustness of the dendrimer in general? Though the speaker mentioned that they tend to be stable up to 60-70 degrees Celsius, are there other areas in which the dendrimer shows frailty? Does the cold cause brittleness or is the range of usable temperatures broad? Finally, Considering the reactivity of amines, how well would the polymer work in acidic or basic environments? Does it break down? The technology itself is very interesting, but there seems to be many areas of it that went undiscussed or are still unexplored.

Though there was some lack of fully defined explanations on several things, he did have all the data required to make a clear case for the DNT product value and progress. Furthermore, Heinzelmann understood the material he was discussing and answered the questions that were asked clearly and with specific and useful responses. Overall the lecture was well presented.

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Review of Joseph Heinzelmann’s Synthesis, Applications, & Commercial Development of Dendrimers

by shieun on Mar.07, 2010, under ChemSem 07, _Spring 2010

Joseph Heinzelmann brought into focus the business aspect of chemistry this week. He is the product manager of Dendritic Nanotechnolgies, Inc. (DNT), a part of a larger company, Starpharma, based in Australia. Starting off in organic synthesis, Heinzelmann moved on to work as a business manager before assuming his present role at DNT.

Two product lines that Heinzelmann is responsible for are Priostar Dendrimers and PAMAM Dendrimers. Dendrimers are spherically shaped molecules that can be divided into four parts: the core, generation, interior void, and the surface groups. The core can be anything with at least 2 amine groups. Each layer of branching, called a generation, is appended on through a Michael’s addition reaction. The number of generations, how large the dendrimer can become, is determined by the interior void, the free space between the branches that decreases with each branching. The void space is considered around the 3rd or 4th generation – drugs or imaging agents can be inserted in these compartments, like luggage for the dendrimer. Constituents of the surface groups determine the actual chemistry of the dendrimer as it composes the outermost region of the molecule. Dendrimers can range in size from 1-10 nm and the size determines where it can travel in the body, how the body will manage it. Because they are basically plastic, dendrimers are excreted from the body normally (through the kidneys).

Some of the dendrimer’s interesting characteristics show promise as a biomedical solution. Cross linkers on the surface create high density reaction area and the internal structure provides strength without the loss of flexibility, a common problem with most polymers. Many possibilities lie in surface modifications to improve the manner of interaction with other reagents. For example, during a heart attack the body secretes certain products. Dendrimers can bond to antibodies and antigens in blood and because they can be lined up, it is easier to determine whether the person is having a heart attack or if they are suffering from heart burn.

Hopeful applications for dendrimers may be in fighting cancer. Most therapy for cancer involves the killing of healthy cells. Incorporating existing cancer drugs with the “smart” nanotechnology of dendrimers, the cancer cells can be targeted avoiding the deterioration of healthy cells. Imaging agents can also be incorporated and with MRI scanning the progress of the drug can be observed in real time. Gene therapy is another possibility since dendrimers can be made the same size as siRNA (small interfering RNA) they would be able to carry genetic coding. However, like many hopeful patents, dendrimers face the problem with manufacturing problems, government restrictions, financial restrictions, and safety issues.

Another issue Heinzelmann wanted to focus on was the career possibilities for chemistry majors, aside from the usual route. Himself only obtaining a Bachelors in Chemistry, Heinzelmann stressed that it was not necessary to earn a PhD in science to achieve a fulfilling career life in chemistry. In the business world, there is a need for marketing, supply chain management, sales, and regulatory positions with the government. An open mind keen on learning proved to be a key factor in success.

Heinzelmann’s presentation topic was not wholly new as we have had other seminars on dendrimers. However it was refreshing to have the basic foundation that Heinzelmann gave on dendrimers, as the other speakers assumed that we had this knowledge leaving the audience a bit befuddled. Since we are reaching our last guest speakers, a slew of questions bombarded Heinzelmann from all across the amphitheater. Many of my own questions were asked and answered, although it remains unclear what the present stage dendrimers are at in relation to being in practical use. During the presentation, Heinzelmann mentioned that due to the discouragement of ever getting dendrimers past that large mountain of regulations and testing, many people left the project. In relation to cancer, I wondered if dendrimers really are the future to cure cancer.

Laymen’s Summary of Seminar: Dendrimer’s root word is Greek for ‘tree-like branching’. The molecule looks like a sphere, or even better, a strange planet covered with tall trees, something you would see in the world of the Little Prince. Dendrimers can carry other small molecules, such as drugs, in the pockets of space between the branches. In the body, the size of the dendrimer determines where it can go, giving us more ability to decide what to do with it. Side note: You do not need a PhD in science to be great at chemistry or have a great career in the chemistry world.

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Chemistry Seminar on 03/05/10

by jongho on Mar.07, 2010, under ChemSem 07, _Spring 2010

This week’s chemistry seminar was presented by Mr. Heinzelmann, a current product manager at Dendritic Nanotechnologies (DNT). After obtaining a B.S. degree in chemistry from Albion college, he thought deeply about his future career working as a chemist. He decided working in a lab alone for many hours was not a type of thing he wanted to do for the rest of his life, so he moved onto obtain an MBA from Northwood University. He has been  working at DNT for 6 years, and he demonstrated to us chemistry major undergraduate students that there are many more ways we can take after we graduate depending on our own interest. The title of his presentation was “Synthesis, applications and commercial development of dendrimers.”

I learned that DNT is owned by Starpharma. DNT has 69 patents issued and owns two product lines of dendrimers. Manufacturing steps of DNT were as follows: prepare bifunctional molecule -> attach methyl ester -> attach ethelyne diamine. The core molecule has four surface groups, and each additional generation (attaching ethelyne diamine) doubles the surface groups. Thus, dendrimer starts with 5.2nm in size, but grows bigger as its generation increases. In the middle of dendrimer, there is a room for solvent or other molecules to get in, and this room serves its purpose well when used to deliver cancer treating drugs for instance.

My questions during his seminar included: 1) How long do you think it will take for this dendrimer to be used in real life as a cancer delivering agent? 2) What is the biggest generation you have created and does it grow in size forever? and 3) How does different sized dendrimer find its way to the right place in the body?

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Review on Insights Into the Chemistry Business

by quines on Mar.07, 2010, under ChemSem 07, _Spring 2010

Our lecturer, Joseph Heinzelmann, product manager from Dendritic Nanotechnologies was able to give a presentation on not only dendrimers, but also on the chemistry industry and career options that is relevant for us. I enjoyed this presentation because he was able to explain clearly about the dendrimers.

His presentation focused on the PANAM dendrimer. He made a statement that dendrimers are carefully architectured polymers that consist of a core and several layers categorized by generations. In addition to that, dendrimers can have many different surface groups. It was named dendrimer for its treelike branching. Usually dendrimers are 1-10nm and built with some organic chemistry reactions. I learned that dendrimers do a variety of things. They can be crosslinkers, have suface modification, and carry drugs in their void spaces.

Overall, I enjoyed this seminar because I was able to learn more about the chemical industry. It seems like an interesting area of chemistry if you do not want to be stuck in the lab, as Heinzelmann put it. In this seminar we had an abundance of questions as we are winding down to only a few more seminars left. Because of this, I was able to learn a great deal more about dendrimers.

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Synthesis, Applications and Commercial development of Dendrimers

by choig on Mar.07, 2010, under ChemSem 07, _Spring 2010

The seminar that was held on March 4, 2010 was “Synthesis, Applications and Commercial development of Dendrimers.”  The guest speaker for this presentation was Joseph Heinzelmann who graduated from Albion College with B.S.in Chemistry.  Following that he focused on organic synthesis and started working on dendrites.

Joseph Heinzelmann started his presentation with DNT/ Starpharma after he introduced himself.  Starpharma is the $150 M market Cap Brotech Company in Melbourne. DNT is mostly involved in the production and study of dendrimers. Dendrimers are carefully architected, highly organized polymers. They are also nomenclature, composed by small core, inferior void and surface group. Furthermore, they are cross linkers which work as surface modification and ball bearing. Additionally, void space allows for carrying molecules like drug or imaging agents.

More interesting thing is that in nanotechnology, the size helps to ligands could be targeting group, and drug could be things that kill cancer. Moreover, some dendrimers can be modified to carry genetic code. Therefore, dendrimers can be useful treatments for various different diseases such as cancer and heart attacks. However, it cannot be used in prescription because it has not been proved to be safe. Now, he is working on these problems hoping dendrimers to be useful drug that kills cancer cell not harming any other healthy cells.

Overall, this presentation was pretty interesting and attractive because a lot of people are struggling with cancer and people who have cancer also struggling with side effects from the cancer drug or treatments. I had questions for this seminar and one of them was how the dendrimers structurally related like bonding. He answered with drawing bonding and mechanisms on the board.

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Synthesis, Applications and Commercial Development of Dendrimers

by Andrew Yang on Mar.07, 2010, under ChemSem 07, _Spring 2010

The presentation this week (03-04-2010) was titled “Synthesis, Applications and Commercial Development of Dendrimers”. It was given by Joseph Heinzelmann, who is the product manager for DNT/Starpharma. Joseph graduated high school in 200, then went to Albion College.

His company specializes in two different product lines, specifically dendrimers. Dendrimers are carefully architected, sphere, small polymers. The size of these dendromirs range between one to ten nano meters, and are built using basic organic chemistry. Dendrimers can be useful treatments for all sorts of different diseases, including cancer and heart attacks. Joseph is hopeful that these dendrimers will be able guide cancer killing drugs specifically to cancer cells, and not destroy other healthy body cells. Dendrimers can also help enhance heart attack detectors, which is very important. Because of the specific shape of the dendrimer, in any type of filtration device, or membrane, it can be used to create an osmolarity, which in some situations can become very important. The only problem to this research, is that it is old. Dendrimers are not used in perscription drugs because it has not been proven to be safe. Currently, Joseph is trying to find a solution to this and the issue of the budget. Joseph Heinzelmann presented his work very effectively, and kept his audience attentive. He spoke clearly and without an accent. Many questions followed the question and answer session, which he answered effectively.

Overall, I thought the presentation was interesting to listen to. The fact that this technology could be used to treat cancer, and detect heart attacks was very interesting. Although I am very interested in cancer treatment, this type of technology did not appeal to me. It is not something that I would like to spend my time researching.

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Synthesis, Applications and Commerical Develpment of Dendrimers

by mastera on Mar.05, 2010, under ChemSem 07, _Spring 2010

The lecture this week was about the synthesis, production, and uses of dendrimers. The speaker was Joseph Heinzelmann, Product Management, Dendritic Nanotechnologies, Incorporated. DNT is a subsidiary of Starpharma Holdings Limited, and is mostly involved in the production and study of dendrimers.

The topic delivered this week was fairly interesting in that it not only included information concerning the synthesis and production of a new technology that could potentially have applications to curing cancer, but it also included information concerning job potentials in the field of chemistry. One of the things that I learned from this lecture was that the spherical structure of dendrimers give them a larger surface area, allowing them to have a higher density for reactions. Another thing that I learned from this lecture was that dendrimers provide a better function than other polymers because of their spherical nature. This is because the spherical shape of the dendrimer prevents it from escaping through the porous materials in the body, whereas polymers are typically long skinny chains that can easily fit through pores. One thing that would be interesting to find out more about is how dendrimers are synthesized, more specifically how the spherical shape of a dendrimer is formed.

If I were to describe the topic of this lecture to one of my non-science friends, I would probably say that the lecture was about how a chemical that has potential in fighting cancer is created and produced, and how the companies that make it market the product to other companies.

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Dendrimers and the Business Side of Chemistry

by kgardner on Mar.05, 2010, under ChemSem 07, _Spring 2010

Joseph Heinzelmann came to talk to us about some of the business sides of a degree in chemistry. He is a worker for Dendritic Nanotechnologies, Inc, or DNT, where he began working in 2004. This talk was very interesting, first with the subject matter on dendrimers, then with the insight into the different options that are out there for graduates with chemistry degrees.

A dendrimer is a molecule that is made up of a core, and has branches coming out of it creating some very large molecules. There are surface groups on dendrimers that are used for reacting with destinations, and there are void spaces within the molecule where substances can be packed and carried. A current use for dendrimers is to find out if an individual is having a heart attack. Some future uses include work with cancer and gene therapy. In the case of cancer, dendrimer would be loaded with cancer drug and injected into the body. The surface groups would be made so that they will interact with the cancer wherever it is in the body, so the dendrimer would be caught and the drug would be unloaded before the dendrimer would be removed from the circulation. The dendrimers that I have just described and what most of Heinzelmann’s talk was about are the PAMAM dendrimers. These are made by repeated action of starting with the core molecule and adding methyl acrilade, after this ethylene diamine is added. These two steps are repeated, each time adding another generation until the desired size of the dendrimer is established.

I would describe this talk to a non-science friend as being partly about creating carrier molecules for anti-cancer drugs and partly about the business side of chemistry.

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