Novel Hydrogels for Rhythmic Pulsatile Drug Delivery

摘要: We are investigating an autonomous glucose-driven hydrogel/enzyme-based device prototype for rhythmic, pulsed delivery of gonadotropin releasing hormone (GnRH). The employs a pH-sensitive hydrogel membrane in conjunction with the enzyme glucose oxidase. This system delivers GnRH rhythmic pulses when exposed to constant level glucose. These result from pH oscillations inside that created by unstable nonlinear feedback between permeability and production acid Previous versions this utilized p(N-isopropylacrylamide-co-methylacrylic acid) p(NIPA-co-MAA) hydrogels, 10 mol% MAA incorporated. With membrane, which undergoes volume transition (VT) near 5, centered around 5 observed. range is too low sustain physiologically buffered media. To shift operating closer physiologic pH, we have sought ways increase transition. In study show increasing side chain length α-alkylacrylic (RAA) comonomer enhances overall hydrophobicity copolymer, shifts VT physiological values. also demonstrate ability such membranes affect alkaline oscillator device.