Swelling-controlled delivery systems

Bajpai, A. K., and Choubey, J. (2006), Design of gelatin nanoparticles as swelling controlled delivery system for chloroquine phosphate, / Mater. Sci. Mater. Med., 17(4), 345-358. 

Mandal, T.K. 2000. Swelling-controlled release system for the vaginal delivery of miconazole. Eur... 

HB Hopfenberg, KC Hsu. Swelling controlled, constant rate delivery systems. Polym Eng Sci 18 1186-1191, 1978. 

P Colombo, R Bettini, P Santi, A De Ascentiis, NA Peppas. Analysis of the swelling and release mechanisms from drug delivery systems with emphasis on drug solubility and water transport. J Controlled Release 39 231-237, 1996. 

The amphiphilic nature of the polyester/PHEMA networks provides gels able to swell in both organic and aqueous media, which prompted us to study them as controlled drug delivery systems [114]. The most valuable characteristic feature of these amphiphilic networks is their potential to sustain the drug delivery... 

Drug delivery induced by swelling may be achieved with swellable polymer layers based on cellulose ethers or acrylates, where with the latter pH-dependent swelling behaviour is feasible [92]. Examples are the oral Chronotopic delivery system [93], the Tune-controlled Explosion ystem (TES) [94,95] and the TIME-CLOCK -System [96-98] (Figure 6.4). 

Figure 6.4. Swelling-induced time-controlled drug delivery systems.

Studies on glucose-induced polymer swelling have focussed on developing membranes that could serve in systems for controlled delivery of insulin to diabetics (3,4). It has been shown that hydrophobic methacrylate copolymers undergo a sharp swelling transition as the pH is decreased from 7 to 6 (3-7). However, the kinetics of the transition are too slow for the proposed application to glucose delivery. 

Korsmeyer, R.W. Peppas, N.A. Macromolecular and modeling aspects of swelling-controlled systems. In Controlled Release Delivery Systems Roseman, T.J., Mansdorf, S.Z, Eds. Marcel Dekker, Inc. New York, 1983 77-90. 

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