Drug-loaded calcium pectinate gel (CaPG) beads were prepared by either mixing, absorption, or swelling method. The effects of drug loading method as well as the drug loading factors (i.e., drug concentration, soaking time in drug solution, type of solvent) on drug content and drug release were investigated. The amount of drug uptake (i.e., drug content) into CaPG beads increased as the initial drug concentration increased and varied depending on the loading method. The in vitro release studies in 0.1 N hydrochloric acid (HCl) and pH 6.8 buffer indicated that the drug loading method affected drug release and release parameter, time for 50% of drug release (T(50)). The mixing method provided a faster drug release and lower T(50) than the absorption method and swelling method, respectively. This is probably due to higher drug content in CaPG beads. The increased concentration of drug in soaking solution and soaking time resulted in higher drug content and thus faster drug release (lower in T(50) values). When using 0.1 N HCl as solvent for soaking instead of water, the drug release was slower owing to the increase in molecular tortuosity of CaPG beads. The drug release was also affected by pH of the release medium in which drug release in 0.1 N HCl was faster than in pH 6.8 buffer.
A new processing method for the production of modified starch, high power ultrasonic treatment (400 W), was applied to native tapioca starch. The effect of processing parameters such as ultrasound amplitude (50 and 100%) and sonication time (10, 20 and 30 minutes) on the properties of the modified starches was investigated. Starch granule morphology observed by scanning electron microscopy (SEM), swelling power, solubility and powder x-ray diffractometry (PXRD) of the obtained ultrasonically treated tapioca starch were determined and compared with native as well as heat-treated tapioca starches. The results from SEM and PXRD showed that the ultrasonic treatment of tapioca starch distorted the crystalline region in starch granules, especially at higher amplitude or sonication time. The swelling power of the tapioca starch increased after treatment with both heat and ultrasound, in which the swelling power of ultrasonically treated starch was higher than that of heat-treated starch. It was found that tapioca starch treated by ultrasound for a certain period of time has an increase in solubility. The increase in the swelling power is associated with water absorption capacity and starch granules solubility.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.