Improving the ultraviolet protection factor of textiles through mechanical surface modification using calendering

The textile modification technique of calendering was used to change the cover factor of wearable textiles in order to improve the ultraviolet protection factor and decrease the amount of ultraviolet radiation transmitted through the fabric. Using optical microscopy and ultraviolet spectrophotometry, the quantifiable changes that occurred after repeated passes through the calender were measured. It was found that after one pass the uncovered area decreased by a factor of two and the ultraviolet protection factor increased by 200%. The thickness and air permeability of treated fabric decreased with repeated calendering. The bending stiffness remained nearly unchanged, and thus the mechanical properties were not altered substantially by the fabric compression.

Construction of IL-13 Receptor α2-Targeting Resveratrol Nanoparticles against Glioblastoma Cells: Therapeutic Efficacy and Molecular Effects

Glioblastoma multiforme (GBM) is the most common lethal primary brain malignancy without reliable therapeutic drugs. IL-13Rα2 is frequently expressed in GBMs as a molecular marker. Resveratrol (Res) effectively inhibits GBM cell growth but has not been applied in vivo because of its low brain bioavailability when administered systemically. A sustained-release and GBM-targeting resveratrol form may overcome this therapeutic dilemma. To achieve this goal, encapsulated Res 30 ± 4.8 nm IL-13Rα2-targeting nanoparticles (Pep-PP@Res) were constructed. Ultraviolet spectrophotometry revealed prolonged Res release (about 25%) from Pep-PP@Res in 48 h and fluorescent confocal microscopy showed the prolonged intracellular Res retention time of Pep-PP@Res (>24 h) in comparison with that of free Res (<4 h) and PP@Res (<4 h). MTT and EdU cell proliferation assays showed stronger suppressive effects of Pep-PP@Res on rat C6 GBM cells than that of PP@Res (p = 0.024) and Res (p = 0.009) when used twice for 4 h/day. Pep-PP@Res had little toxic effect on normal rat brain cells. The in vivo anti-glioblastoma effects of Res can be distinctly improved in the form of Pep-PP@Res nanoparticles via activating JNK signaling, upregulating proapoptosis gene expression and, finally, resulting in extensive apoptosis. Pep-PP@Res with sustained release and GBM-targeting properties would be suitable for in vivo management of GBMs.

INHIBITION OF GASTRIC DEGRADATION OF OMEPRAZOLE USING A pH-SENSITIVE POLYMER AS A BINDER IN TABLET FORMULATION

Objective: This work was aimed at formulating omeprazole tablets using afzelia gum as a binder that is capable of inhibiting the gastric degradation of the drug. Methods: Afzelia gum at different concentrations of 0, 5, 10, 15, 20 and 30% was used as a binder to formulate omeprazole tablets. The tablets were formulated by direct compression and the batches labelled F1 to F6 respectively. A batch containing 15% hydroxypropyl methylcellulose (F7) was also formulated. The tablets were characterized; and dissolution in a pH 1.2 dissolution medium over 120 min period was studied. Aliquots taken every 20 min were analyzed by ultraviolet spectrophotometry to determine the amount of drug released and not degraded. Results: Amounts of drug released and not degraded at time 120 min were 53.1%, 57.3%, 57.8%, 58.8%, 62.1%, 83.4% and 90.0% for F1 to F7 respectively. Conclusion: Afzelia gum at a concentration of 30% is suitable for use as a binder in tablet formulation of omeprazole to ensure substantial inhibition of gastric degradation of the drug.

Development of derivative spectrophotometric method for simultaneous determination of pyrazinamide and rifampicin in cubosome formulation

The ultraviolet spectrophotometry analysis for quantitative assay of drugs is a method accurate, sensitive, selective and reproductive with the advantage of being a simple and less expensive method. In this study, a derivative ultraviolet spectrophotometric method was developed for simultaneous determination of pyrazinamide (PYZ) and rifampicin (RIF). The spectrophotometric method was evaluated according to validation guidelines for specificity, linearity, limits of detection and quantification, precision, accuracy and robustness. The first-derivative spectra were obtained and by the zerocrossing point, the wavelength 247 nm and 365 nm were selected for PYZ and RIF quantification, respectively. No interference from cubosome excipients was detected in the proposed method. The results demonstrated linearity in a range of 4.0 – 12.0 µg/mL with an adequate correlation coefficient for both drugs. The intra and inter-day precision results (RSD < 5%) indicated the reproducibility of the method. The accuracy data showed satisfactory results (RSD < 5%) from recovery test. In addition, the robustness results showed that the PYZ and RIF content were unaffected by the solvent alteration of methanol to methanol:water (99:1, v/v). The derivative ultraviolet spectrophotometric method proved to be an excellent strategy for simultaneous determination of PYZ and RIF.

Incompatibility of remimazolam besylate with Ringer’s acetate infusion resulting in total occlusion of an intravenous catheter

Remimazolam besylate is an ultra-short-acting benzodiazepine derivative recently approved in Japan for general anaesthesia. However, less attention has been paid to the compatibility of remimazolam with infusion solutions, and the mechanism underlying the incompatibility remains unknown. The patient was a 65-year-old man who underwent a high tibial osteotomy. After the induction of general anaesthesia using remimazolam solution (5 mg/mL), we noticed precipitate completely blocking the lumen of the intravenous tube connected to a Ringer’s acetate Physio140 drip. The mixture of remimazolam solution (5 mg/mL) with Physio140 solution immediately resulted in the formation of substantial precipitate. Nuclear magnetic resonance analysis revealed that the precipitate was remimazolam. Ultraviolet spectrophotometry revealed that the mixture of remimazolam solution with higher ratios of Physio140 resulted in significantly lower solubility, concomitant with an increase in pH. It would be important to consider the remimazolam concentration and infusion solution pH to avoid the production of precipitates.