Synthesis, Chloramphenicol Uptake, and In Vitro Release of Poly(AMPS-TEA-Co-AAm) Gels with Affinity for Both Water and Alcohols

Novel copolymeric gels of poly(AMPS-TEA-co-AAm) with superabsorbency in both water and alcohols were synthesized by neutralizing 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS) with triethylamine (TEA) followed by copolymerizing the resulted salt with acrylamide (AAm) in aqueous solutions using N, N'-methylenebisacrylamide (MBAm) as a crosslinker, and ammonium persulfate (APS) as an initiator. By swelling the xerogel of poly(AMPS-TEA-co-AAm) in the drug solution followed by removing the solvent to give drug-polymer conjugate, the incorporation of a model drug, chloramphenicol, into the gels was investigated by using water and alcohols as solvent, respectively. The in vitro drug release profile of the drug-polymer conjugate was investigated in PBS. The results showed that poly(AMPS-TEA-co-AAm) gels exhibited superabsorbency in both water and a series of alcohols; and the alcohol-facilitated uploading of chloramphenicol into the gels was much greater than that achieved in water. The poly(AMPS-TEA-co-AAm) gels exhibited a similar drug release profile with conventional hydrogels; and only part of the drug uptaken by the gels was released as a result of poor aqueous solubility of chloramphenicol.