Crops: A Green Approach toward Self-Assembled Soft Materials

This talk presents novel and emerging concept of generating various forms of soft materials from renewable resources. In future research, developing soft nanomaterials from renewable resources (an alternative feedstock) would be fascinating yet demanding practice, which will have direct impact on industrial applications, and economically viable alternatives. Our continuous efforts in this area led us to develop new glycolipids from industrial byproducts such as cashew-nut-shell-liquid, which upon self-assembly produced soft nanoarchitectures including lipid nanotubes, twisted/helical nanofibers, low-molecular-weight gels and liquid crystals. More recently, we have developed multiple systems based on biobased organic synthesis by chemical/biocatalytic methods for functional applications. We used the ‘chiral pool’ of carbohydrates using the selectivity of enzyme catalysis yield amphiphilic products from biobased feedstock including amygdalin, trehalose and vitamin-C. Amygdalin amphiphiles showed unique gelation behaviour in a broad range of solvents such as non-polar hexanes to polar aqueous solutions. Importantly, an enzyme triggered drug-delivery model for hydrophobic drugs was demonstrated by using these supramolecularly assembled hydrogels. Intriguingly, by combining biocatalysis, with principles of green and supramolecular chemistry, we developed building blocks-to-assembled materials. Also address the advances that have led to the understanding of chiral behaviour and the subsequent ability to control the structure of glycolipid nanostructures, and the resulting impact of this on future material applications. These results will lead to efficient molecular design of supramolecular architectures and nanomaterials from underutilized plant/crop-based renewable feedstocks.

Related References:
1. Vemula, P., John. G. Crops: A Green Approach toward Self-Assembled Soft Materials. Accounts of Chemical Research 41, 769-782, (2008).
2. Vemula, P., Douglas, K., Achong, C., Kumar, A., Ajayan, P., John. G. Autoxidation Induced Metal Nanoparticles Synthesis in Biobased Polymeric Systems: A Sustainable Approach in Hybrid Materials Development. Journal of Biobased Materials and Bioenergy 2, 218-222 (2008).
3. Kumar, A., Vemula, P., Ajayan, P. M., John, G. Silver Nanoparticles Embedded Anti-microbial Paints Based on Vegetable Oil. Nature Materials 7, 236-241 (2008).
4. John, G., Vemula, P. Design and Development of Soft nanomaterials from Biobased Amphiphiles. Soft Matter 2, 909-914 (2006). Front cover page feature.
5. Vemula, P., Li, J, John, G. Enzyme Catalysis: Tool to Make and Break Amygdalin Hydrogelators from Renewable Resources - A Delivery Model for Hydrophobic Drugs. Journal of American Chemical Society 128, 8932-8938 (2006). Highlighted in Green Chemistry 8, 675 (2006).
6. John, G., Zhu, G., Li, J., Dordick J. S. Enzymatically-Derived Sugar Containing Self-Assembled Organogels with Nanostructured Morphologies. Angewandte Chemie International Edition 45, 4772-4775 (2006). Front cover page feature. Angewandte Chemie 118, 4890-4893 (2006).
7. John, G.; Masuda, M.; Jung, J., H; Yoshida, K.; Shimizu, T. “Unsaturation Influenced Gelation of Aryl Glycolipids” Langmuir, 2004, 20, 2060-2065.
8. John, G., Minamikawa, H., Masuda, M. and Shimizu, T. “Liquid Crystalline Cardanyl Glucopyranosides” Liquid Crystals, 2003, 30, 747.
9. John, G.; Jung, J. H.; Shimizu, T. “Morphological Control of Helical Solid Bilayers in High-Axial-Ratio Nanostructures through Binary Self-assembly”. Chem. Eur. J. 2002, 8(23), 5494-5500.
10. John, G.; Masuda, M.; Shimizu, T. “Nanotube Formation from Renewable Resources via Coiled Nanofibers” Adv. Mater. 2001. 13 (10), 715-718.