Polymer-drug interactions

Negative contribution to the enthalpy of mixing as a result of forming drug-polymer interactions. 

Pignatello, R. Eerro, M. Puglisi, G. Preparation of solid dispersion of nonsteroidal anti-inflammatory drugs with acryhc polymers and studies on mechanisms of drug-polymers interactions. AAPS Pharm Sci Tech 2002,5, 1-11. 

Lin, S.-Y. Lee, C.-L. Lin, Y.-Y. Drug-polymer interaction affecting the mechanical properties, adhesion strength and release kinetics of piroxicam-loaded Eudragit E films plasticized with different plasticizers. J. Control. Release... 

Goracinova K, Klisarova L, Simov A, et al. Preparation, physical characterization, mechanisms of drug/polymer interactions, and stability studies of controlled-release solid dispersion granules containing weak base as active substance. Drug Dev Ind Pharm 1996 22(3) 255-262. 

Forster A, Hempenstall J, Rades T. Investigation of drug/polymer interaction in glass solutions prepared by melt extrusion. Internet J Vib Spectrosc 2001 5 6-20 [www.ijvs.com]. 

Chitosan and several of its innumerable derivatives have the ability to form thin membranous films of use in packaging [254-256], encapsulation and drug delivery systems. Due to drug polymer interactions, high viscosity chitosan films showed better sustainable release and the mechanism of release followed Fickian diffusion control with subsequent zero order release [257]. 

Huang J, Wigent RJ, Schwartz JB (2008) Drug-polymer interaction and its significance on the physical stability of nifedipine amorphous dispersion in microparticles of an ammonio methacrylate copolymer and ethylcellulose binary blend. J Pharm Sci 97 251-262. 

Presumptions covalent networks of identical hydrophobicity, drug-polymer interaction, degrada-tion/homogeneous erosion pathway, size and morphology loaded by swelling (see text for deteiils)... 

Obviously, drug physicochemical properties such as solubility, drug-polymer interaction, drug physical state, drug content in the matrix, and the distribution of... 

In conclusion, miscibility of a ternary system (dmg, polymer, and water) depends on the balance between the thermodynamic factors, which in turn are affected by the amount of water absorbed by the system. The extent of water sorption depends on the hygroscopicity of both polymer and dmg, in addition to the strength of the in-termolecular interactions. Thus, a system that has strong drug-polymer interactions. 

The low porosity of compressed tablet may require use of hydrophilic fillers to improve the dissolution rate that may be at the expense of drug/polymer interactions. 

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