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The aim of this study was to develop the electrospun shellac (SHL) and hydroxypropyl cellulose (HPC) blended nanofibers for drug carrier application. The effects of polymer solution and electrospinning parameters, including SHL-HPC ratio, HPC concentration, applied voltage and flow rate, on the appearance of fibers were investigated. Based on the results, electrospun fiber was not obtained when a solution of HPC alone was employed. However, the fibers would be obviously fabricated as SHL was added to the HPC solution. An increase in the SHL ratio in SHL-HPC blended solution could accordingly lead to a remarkable enhance in the fiber diameter. In addition, the continuous nanofibers with less beads were gradually formulated when the HPC concentration was increased. The electrospinning parameters seemed to be significant. The elevation of infusion rate from 0.5 to 1 mL/h would contribute to the preparation of thick fibers with the diameters enlarging from 666.9 to 843.5 nm. With the applied voltage increasing from 15 to 30 kV during the electrospinning process, the fabrication of small nanofibers with the diameters reducing from 843.5 to 741.6 nm would be conducted. In this study, monolaurin (ML), a broad antimicrobial agent, was encapsulated into the SHL-HPC carrier for the purpose of drug delivery application. Regarding the result, the loaded concentration of ML could not be enhanced by introducing HPC to the SHL fibers.

Coconut (Cocos nucifera L.) oil is composed predominately of medium-chain triglycerides which have been reported to be beneficial to human health. It also contains free fatty acids (FFAs) which can combine with glycerol to form monoglycerides, diglycerides, and triglycerides. The analysis of FFAs and their glycerides has been proposed to assess the quality of coconut oil used as raw materials in various industrial fields. The aim of this study was to develop the qualitative method for investigation of FFA and their glycerides in coconut oil using thin layer chromatography (TLC). Coconut oil and standards of FFA and their glycerides were chromatographed separately on Silica gel 60 F254 TLC plates using hexane: ether: acetic acid (60:40:1) and hexane: ethyl acetate: acetic acid (60:40:0.5) as solvent systems A and B, respectively. The spots on developing TLC plates were detected and compared using 254-nm UV light and iodine vapor. The results showed that the resolution of solvent system A was better than that of solvent system B. However, both solvent systems were used to confirm the results. The retention factor (Rf) values of the components were in good agreement with their polarity. This method should provide a guideline for qualitative analysis of coconut oil.

UV-Vis spectrophotometric method was validated for the stability assessment of 5% extemporaneous vancomycin eye drops in different vehicles. The eye drops were extemporaneously prepared by dissolving vancomycin in various vehicles, including sterile water for injection (SWI), 0.45% normal saline (0.45%NSS) and artificial tear. The solutions were stored at room temperature and in refrigerator for 30 days. The content of vancomycin was measured by UV-Vis spectrophotometer at 280 nm. UV-Vis Spectrophotometric method was validated according to ICH guideline. The results indicated that the method was precise and accurate. The calibration curve was linear with r2 = 0.9997 in the range of 40-160 μg/mL. LOD and LOQ were 3.39 and 10.26 μg/mL, respectively. The results showed that the percentage of vancomycin residual concentation in SWI and 0.45%NSS was decreased to less than 90% after storage at room temperature for 8 days, whereas the residual concentration of vancomycin in artificial tear was less than 90 % after 10 days in room temperature. Meanwhile the percentage of vancomycin residual concentation in all formulations was remarkably decreased to less than 90% after storage in refrigerator for 17 days. The physical appearance of eye drops in artificial tear remained unchanged. However the observed color of other formulations was gradually changed to yellow in day 7 at room temperature and day 17 in refrigerator. The pH values of all preparations were within the general U.S. pharmacopeia national formulation range of 2.5-4.5. In conclusion, the eye preparations of 5%w/v vancomycin in all selected vehicle were stable for 17 days in refrigerator (2-8°C).