An electrospun fiber of polyvinyl(pyrrolidone) (PVP)-Tween 20 (T20) with curcumin as the encapsulated drug has been developed. A study of intermolecular interactions was performed using Raman spectroscopy, Fourier transform infrared (FT-IR), differential scanning calorimetry (DSC), and X-ray diffraction (XRD).The Raman and FT-IR studies showed that curcumin preferrably interacted with T20 and altered PVP chain packing, as supported by XRD and physical stability data. The hydroxyl stretching band in PVP shifted to a lower wavenumber with higher intenstity in the presence of curcumin and PVP, indicating that hydrogen bond formation is more intense in a curcumin or curcumin-T20 containing fiber. The thermal pattern of the fiber did not indicate phase separation. The conversion of curcumin into an amorphous state was confirmed by XRD analysis. An in vitro release study in phosphate buffer pH 6.8 showed that intermolecular interactions between each material influenced the drug release rate. However, low porosity was found to limit the hydrogen bond-mediated release.Key words curcumin; fiber; electrospinning; interaction; porosity; polymeric drug delivery system Curcumin is the major constituent of turmeric rhizome (Curcuma sp.).1) Curcumin has a number of demonstrated pharmacological effects, such as antioxidant, anti-inflammatory, anticancer, hepatoprotective, 1) antimicrobial, and antiviral. 2)Clinical trials have proven that curcumin is well tolerated by the body, with a maximum dose of 12 g daily.3) Unfortunately, the efficacy of curcumin is limited by its poor solubility in water, as well as its instability under light, heat, and alkaline conditions.1) The solubility of curcumin in aqueous buffer (pH 5) is reported to be 11 ng/mL.3) Moreover, the absorption of curcumin in the gastrointestinal tract is very low, leading to poor bioavailability (in animals and humans).2) Therefore, designing an effective delivery system is necessary in order to address the limitations of curcumin use. 1-3)A wide range of drug delivery systems has been developed to improve the bioavailability of poorly soluble drugs, including fast-dissolving tablets, 4) incorporation into a hydrophilic complex, 1) micellization, and solid dispersion. 5) Electrospinning, a technique of producing thin strands of fiber using high voltage, has opened up opportunities in the development of drug delivery systems. An optimized electrospinning process can produce nano-sized fibers. 6)The high surface area and porosity of these electrospun fibers are advantageous in their use as carriers for poorly water-soluble drugs.5) The high surface area generally increases the dissolution rate of the incorporated drug, thus potentially enhancing its bioavailability. 5)Therefore, the incorporation of curcumin into an electrospun fiber is expected to improve its oral bioavailability.Tailoring a suitable drug-loaded fiber requires careful selection of materials, in addition to an optimized production process and environment. Generally, the drug is mixed with a polymer s...

The unique three-dimensional pore structure of KCC-1 has attracted significant attention and has proven to be different compared to other conventional mesoporous silica such as the MCM-41 family, SBA-15, or even MSN nanoparticles. In this research, we carefully examine the morphology of KCC-1 to define more appropriate nomenclature. We also propose a formation mechanism of KCC-1 based on our experimental evidence. Herein, the KCC-1 morphology was interpreted mainly on the basis of compiling all observation and information taken from SEM and TEM images. Further analysis on TEM images was carried out. The gray value intensity profile was derived from TEM images in order to determine the specific pattern of this unique morphology that is found to be clearly different from that of other types of porous spherical-like morphologies. On the basis of these results, the KCC-1 morphology would be more appropriately reclassified as bicontinuous concentric lamellar morphology. Some physical characteristics such as the origin of emulsion, electrical conductivity, and the local structure of water molecules in the KCC-1 emulsion were disclosed to reveal the formation mechanism of KCC-1. The origin of the KCC-1 emulsion was characterized by the observation of the Tyndall effect, conductometry to determine the critical micelle concentration, and Raman spectroscopy. In addition, the morphological evolution study during KCC-1 synthesis completes the portrait of the formation of mesoporous silica KCC-1.

The double-layer Aurivillius phases Pb 1-2x Bi 1.5+2x La 0.5 Nb 2-x Mn x O 9 (x = 0, 0.1, 0.3, and 0.5) were synthesized by a molten salt method using a mixture of K 2 SO 4 /Na 2 SO 4 . The effect of composition on the structure, morphology and dielectric properties was investigated. X-ray diffraction showed that single-phase samples with a non-polar, orthorhombic A2 1 am structure were obtained for x = 0, 0.1 and 0.3. The unit cell becomes more orthorhombic with increasing x as the degree of distortion of the BO 6 octahedra in the perovskite layer increases. Raman spectroscopy showed the typical modes of the orthorhombic double-layer Aurivillius structure and indicated that the La 3+ ions prefer to occupy the perovskite A-site, Mn 3+ occupies the B-site, and the Pb 2+ ions are found in the Bi 2 O 2 layer. The morphology of the samples was probed by scanning electron microscopy, which showed anisotropic, plate-like crystallites that increased in size with increasing x. The dielectric constant significantly increased with x, and the ferroelectric properties became more relaxor-like.

This research aims to analyze the factors that influence the role of Small and Medium Enterprises (SMEs) on employment, namely capital, sales volume, type of business, length of business, and wages. Empirical data is presented to prove that the role of small and medium enterprises on employment is influenced by capital, sales volume, type of business, length of business, and wages. Multiple regression analysis through the SPSS program was used as a research test tool. The research data was obtained from SMEs businesses, Central Bureau of Statistics and the SMEs Office to test scientifically whether capital, sales volume, type of business, duration of business, and wages affect employment. Research results show that the duration of the business influences the absorption of labor while capital, sales volume, type of business, and wages do not affect employment.