Research and development of a thermo-switchable membrane for drug delivery

• Main Authors: Lin, Yih-Yih, 林意毅
• Other Authors: Chen Ko-Shao
• Format: Others
• Language: en_US
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/26413886386013717954

博士 === 大同工學院 === 機械工程研究所 === 84 === The fact that liquid crystal have a gel-liquid cryatal phase transition temperature (Tc) is well known, and it is expected that the permeation of chemicals through the liquid crystal embedded membrane might be controlled by a temperature change across the Tc. Thermophysical property of cholesteryl olyel carbonate (COC) was determined by thermal analysis and microscopic Fourier transform infrared spectroscopy with differential scanning calorimetry to confirm its thermo-responsible function. Two endothermic peaks due to phase transition were found on the DSC thermogram.Moreover, the peakintensity of several IR spectra changed just according with the phase transition of COC. On the other hand, the change of band intensity in the cooling process underwent inversely to that in heatint process. This suggests the COC has thermo-responsible function. The COC-embedded membranes were prepared by vaccum filtration method at different manufacturing temperatures and the stored at different temperatures. Salbutamol sulfate was used as a model drug across this COC-embedded membrane. The adsorbed amount of COC increased linearly with the oncrease of COC concentration used. Also, the penetration rate of drug through the membtane was controlled by the adsorbed amount of COC on the membrane. Effects of manufacturing temperature and storage conditions on the thermal properties and drug penetrability of COC-embedded membranes were also examined. It is evident that both manufacturing temperature and storage temperatures significantly affected the characteristic of membranes. The higher manufacturing remperature or storage temperature, the better alignment of COC in membranes, that made the superior regularity for grug across the membranes. In vitro permeation study for drug through hairless rat skin with the COC-embedded membrane on the stratum corneum side were carried out in the response to a temperature change. Carbomer gels were used as drug reservoirs and the results showed that an on-off switching penetration behavior of drug through the membrane in rersponse to the temperature cycle. The possibility of applying this functional membrane for the development of mermo-responsive TDDS has been confirmed.