Doxorubicin is cytotoxic anthracycline antibiotic drug used in cancer treatment. The drug's efficacy in various kinds of cancer made its usage dominant for treating cancers. In this study, we determined the solubility of the doxorubicin in three different polymers, i.e., poly (N-isopropyl acrylamide), polyethylene glycol, and polyvinyl pyrrolidone, to increase the doxorubicin's drug efficacy on the targeted tumor site. We investigated the doxorubicin-polymer interactions with carbon-nanotube in the aqueous environment for the targeted delivery application using classical molecular dynamics simulations. An in-depth atomistic insight into polymer interaction with the drug/carbon-nanotube/water is obtained within the study. We have critically analyzed various properties such as interaction energy, hydrogen bonds between polymer-drug and polymer-water, the diffusion coefficient of the drug, end-to-end distance, radius of gyration of the polymer chains, and finally, drug density contours for different drug to polymer ratios. Our results explain the selection of effective monomer chain length of polymer and the suitability of the polymer carrier with doxorubicin.

The aggregation behavior of asphaltene in the toluene-hexane mixture is systematically investigated using experimental techniques such as optical microscopy and Fourier-transform infrared spectroscopy (FTIR) combined with molecular dynamics (MD) simulations. The optical images of various asphaltene concentrations are processed to determine the size of asphaltene aggregates. FTIR is performed within our work in order to understand the formation of aggregates and its interaction with the solvent mixture. MD simulations are employed to achieve atomistic insights into the aggregation behavior of asphaltene. The end-to-end distance of the asphaltene molecule is calculated for various asphaltene concentrations in the toluene-hexane mixture. The dynamical properties of the asphaltene aggregates such as the diffusion coefficient and shear viscosity are calculated. Further, an in-depth analysis of the density contours is performed to probe the clusterization of asphaltene. Thus obtained structural and dynamical properties of the asphaltene aggregates in the toluene-hexane mixture are compared with our experimental findings. Our results thereby highlight the importance of the combined experimental and theoretical study to achieve deeper and better insights into the aggregation behavior of asphaltene in toluene-hexane mixture.