@article { ISI:000297470800009, title = {pH Sensitive graft copolymers for zero order drug release: a mechanistic analysis}, journal = {Drug Development and Industrial Pharmacy}, volume = {38}, number = {1}, year = {2012}, month = {JAN}, pages = {73-83}, publisher = {INFORMA HEALTHCARE}, address = {TELEPHONE HOUSE, 69-77 PAUL STREET, LONDON EC2A 4LQ, ENGLAND}, abstract = {

Aliphatic polyesters containing pendent unsaturation were synthesized by the polycondensation of a diol, dicarboxylic acid and glycidyl methacrylate. Grafting methacrylic acid (MAA) resulted in graft copolymers containing polyester backbone and MAA grafts. Depending on composition, the polymers swelled extensively and eroded or dissolved at near neutral pH but remained in collapsed state at acidic pH. Three representative drugs differing in solubility, viz., Diltiazem hydrochloride (DH), Indomethacin (IM) and Verapamil hydrochloride (VH) were released at constant rate from tablets made by compressing spray-dried microparticles. The release of DH at constant rate has been attributed to increase in diffusion coefficient of the drug from the swollen layer of matrix. The release of IM and VH at constant rate was governed by erosion and was enhanced in matrices which undergo dissolution. The release rate was enhanced with increasing MAA content and the frequency of grafts along the polyester backbone. Once a day dosage forms for drugs differing in solubility have been developed using a single polymer matrix which is easy to manufacture.

}, keywords = {Diffusion, erosion, Graft copolymer, matrix tablets, microparticles, spray drying, sustained release}, issn = {0363-9045}, doi = {10.3109/03639045.2011.590991}, author = {Muthusamy, Ramesh and Kulkarni, Mohan Gopalkrishna} } @article { ISI:000382587400004, title = {Encapsulation of yeast (Saccharomyces cereviciae) by spray drying for extension of shelf life}, journal = {Drying Technology}, volume = {34}, number = {11}, year = {2016}, month = {JAN}, pages = {1307-1318}, publisher = {TAYLOR \& FRANCIS INC}, address = {530 WALNUT STREET, STE 850, PHILADELPHIA, PA 19106 USA}, abstract = {

The objective of the present work was to encapsulate yeast using different carrier materials and examine their efficacy in retaining viability of cells after spray drying. Slurry containing yeast cells along with known amount of carrier material (maltodextrin, corn starch, gum arabic, acacia gum, polyethylene glycol 8000, -cyclodextrin, and skimmed milk powder, one at a time) was added and served as feed. Among these carrier materials attempted, corn starch and maltodextrin showed the best results with respect to powder yield (59\%, w/w) and cell survival (80.5\%), respectively. However, considering both survival and powder yield (67 and 59\% w/w, respectively), corn starch was observed to be the most suitable carrier material.

}, keywords = {Cell viability, Encapsulation, freeze-drying, spray drying, Yeast}, issn = {0737-3937}, doi = {10.1080/07373937.2015.1112808}, author = {Chandralekha, A. and Tavanandi, A. Hrishikesh and Amrutha, N. and Hebbar, H. Umesh and Raghavarao, K. S. M. S. and Gadre, Ramchandra V.} } @article {45579, title = {Nonconventional method for drying of Pseudomonas aeruginosa and its comparison with conventional methods}, journal = {Drying Technology}, volume = {37}, year = {2018}, month = {MAY}, pages = {839-853}, type = {Article}, abstract = {

In this study, preparation of dried cultures of Pseudomonas aeruginosa using nonconventional drying method, namely, low-temperature low-humidity (LTLH) drying was investigated. The effect of carrier materials (whey protein, corn starch, and trehalose) was examined one at a time and also in combinations (to explore the synergistic effect). The results were compared with those obtained using spray drying and freeze drying in terms of cell survival and dry cell powder yield. The powder samples were analyzed also for morphology, flowability, particle size, and moisture content. In LTLH drying, good cell survival was observed along with high powder yield when compared with that in spray drying. Corn starch showed the highest cell survival (91\%) and powder yield (94\%, w/w) among the carrier materials employed besides resulting in good cell survival (65\%) even after a storage period of 6 months.

}, keywords = {cell survival, Encapsulation, freeze drying, Low-temperature low-humidity (LTLH) drying, Pseudomonas aeruginosa, spray drying}, issn = {0737-3937}, doi = {10.1080/07373937.2018.1469140}, author = {Umashankar, K., and Chandralekha, A. and Dandavate, T., and Tavanandi, H. A. and Raghavarao, K. S. M. S.} }