February 1, 2010
Amrita School of Engineering, Coimbatore
Chemotherapy, radiational therapy or surgery is mainly used for treatment of cancer today. Cytotoxic drugs, however, are limited in that they destroy healthy cells in addition to cancerous cells. Moreover, the intrinsic or acquired multidrug resistance of cancerous cells becomes a problem.
Now research is being conducted into nano dendritic polymers that can carry cytotoxic drugs into the body for targeted annihilation of cancerous cells alone. ‘This can also help in minimizing the intrinsic or acquired multi-drug resistance of cancerous cells,” explained Mr. Krishnan Namboori, Research Associate at CEN.
Dendritic molecules are highly symmetrical and characterized by structural perfection. As part of the Computational Chemistry Group of CEN, Mr. Krishnan performs computational analyses to help understand the behavior of these polymers better. “Our computational analysis provides an insight into various factors affecting cancer drug delivery,” he said.
A computational model of the sample is generated and subjected to geometry optimization. Energy of the system is determined based on first principles. Electrostatic, hydrophobic and hydrogen bond interactions that take place during entrapment of drugs within the dendritic polymer are studied. The covalent and electrostatic interactions between the drug and surface of the polymer are analyzed.
“Molecular simulations were used to study the various properties of Polyamidoamine (PAMAM) dendrimers both in equilibrium as well as in the transient or steady-state flows,” Mr. Krishnan explained further. “We used the term “insilico”, implying that ours was a computational study, meaning that the experiment was done on silicaware, ie. computer. Modeling and simulation are essential steps in computational material sciences and life sciences.”
A paper titled, INSILICO ANALYSIS OF NANO POLYAMIDOAMINE (PAMAM) DENDRIMERS, based on the initial work completed was accepted for oral presentation at the International Conference on Nano Sciences and Technology (ICONSAT-2010), that will be conducted at IIT-Bombay during February 17-20, 2009.
Authors of the paper include Vasavi C.S., Sriram Ramakrishnan, Sruthy Anna Cherry and Anjitha P.S., students of M Tech (Biomedical Engineering). The paper explains modeling and simulation of the molecules (drugs and PAMAM) and their interactions. The conference paper will be published in International Journal of Nanoscience, World Scientific, Singapore (IJN).
“Nano dendritic polymers are interesting to study because of their diverse chemical properties and their safety for use in the body. We will determine and characterize interactional energy. We will also be able to identify the interactions as covalent or electrostatic. An insight into these analyses will help us study how the molecular properties help in anticancer drug delivery.”
The conference will feature invited talks from international experts including Prof. CNR Rao (JNCASR, Bangalore, India), Christian Plank (Technische Universität München, Germany), Ding Jun (National University of Singapore, Singapore), Elena A. Rozhkova (Argonne National Laboratory, USA), G.K. Dey (BARC, Mumbai), K. Krishnan (University of Washington, Washington, USA), Katsuhiko ARIGA (National Institute of Materials Science, Japan), Mohamed S. El-Shall (Virginia Commonwealth University, USA).