|
Surface modification of starch grains by adsorption of stearic acid using supercritical fluid technology |
|---|---|
| รหัสดีโอไอ | |
| Title | Surface modification of starch grains by adsorption of stearic acid using supercritical fluid technology |
| Creator | Thanakorn Khroengkhamjornki |
| Contributor | Poj Kulvanich, Jittama Chatchawalsaisin |
| Publisher | Chulalongkorn University |
| Publication Year | 2552 |
| Keyword | Stearic acid, Stearic acid -- Absorption and adsorption, Starch, Excipients, Drugs -- Coatings, กรดสเตียริก, กรดสเตียริก -- การดูดซึมและการดูดซับ, สตาร์ช, สารปรุงแต่งยา, ยา -- สารเคลือบ |
| Abstract | The rapid expansion of supercritical solution with a nonsolvent (RESS-N) was applied to modify the surface of corn starch grains by coating with stearic acid. The effects of temperature and pressure of scCO2, and ratio of starch and stearic acid on the surface modification of starch grains were investigated. Coated starches were characterized using scanning electron microscopy (SEM), laser light scattering particle size analysis, moisture absorption, powder flowability and density measurement, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray powder diffraction (XRPD) and Fourier transform infrared (FT-IR) spectroscopy and was applied as lubricant in tabletting process in comparison with stearic acid and magnesium stearate. The pressure of scCO2 did not affect but temperature of scCO2 and ratio of corn starch and stearic acid were found to be the influential factors on surface modification of starch grains. SEM images showed that stearic acid deposited onto the surface of starch grains forming a thin, uniform and smooth film when reducing the content of stearic acid using pressure of 3000 psi and temperature of 60 °C. This result was supported by an increase in particle size of coated starch which corresponding with the amount of stearic acid used in the mixture. The gravimetric vapour sorption analysis of coated starches showed the percentage of mass change lower than uncoated corn starch, this result corresponding with the result obtained from the determination of moisture absorption property using Karl Fischer method. It indicated that coated starches were coated with stearic acid, a hydrophobic material, almost did not absorb moisture. The bulk and tapped density, compressibility index and apparent density showed different between uncoated corn starch and coated starch. Physicochemical characterizations of coated starches indicated that no change and/or evidence of interaction between starch and stearic acid. The stearic acid coated starches could be applied as a lubricant in tablet formulations. |
| URL Website | cuir.car.chula.ac.th |
