Investigations into the synthesis of a nucleotide dimer via mechanochemical phosphoramidite chemistry

Liquid-assisted mechanochemistry as a versatile approach for the coupling of a nucleoside phosphoramidite with a 5′-OH partially protected nucleoside has been investigated. Noted advantages over reported methods were a simplified reaction protocol, a drastic reduction in the use of toxic solvents, the facilitation of mechanochemical reactions through the improved mixing of solid reagents, and low hydrolytic product formation.

Development and Validation of an RP-HPLC Method for the Determination of Vinpocetine and Folic Acid in the Presence of a Vinpocetine Alkaline Degradation Product in Bulk and in Capsule Form

An alkaline-forced degradation hydrolytic product of vinpocetine was prepared and characterized by 1H-NMR, FTIR spectroscopy, and MS. Subsequently, a simple, selective, and validated reversed-phase HPLC method was developed for the simultaneous estimation of vinpocetine and folic acid in the presence of a vinpocetine alkaline degradation product. Chromatographic separation was achieved using an isocratic mobile phase consisting of acetonitrile–0.02 M KH2PO4 [containing 0.2% (v/v) triethylamine and adjusted to pH 6 with orthophosphoric acid; (80 + 20, v/v)] at a flow rate of 0.9 mL/min at ambient temperature ona Eurospher II C18 (250 × 4.6 mm, 5 μm) column, with UV detection at 280 nm for folic acid and 230 nm for vinpocetine and its alkaline hydrolytic product. Linearity, accuracy, and precision were found to beacceptable over a concentration range of 12.5–200 μg/mL for vinpocetine and 1–16 μg/mL for folic acid. The proposed method was successfully applied for the determination of both drugs and avinpocetine hydrolysis product in a laboratory-prepared mixture and in a capsule containing both drugs.

The Voltammetric Study of β–Glucosidase Hydrolytic Product with Modified Electrode

The novel modified electrode of voltammetric technique was applied to detect p-nitrophenol quantity released from the synthetic substrate p-nitrophenyl-β-D-glucopyranoside (pNPG) for β-glucosidase activity measurement. The results from the developed bismuth film modified screen printed carbon electrode (Bi/SPCE) for p-nitrophenol detecting, can be used for enzyme activity assay during purification steps. The further work, the condition of convenient voltammetric method will be optimized the condition suitable for applying to the β-glucosidase enzyme purification from Terminalia ivorensis C. seeds.

Fabrication of Aluminiferous Nanofibers by Simple Hydrolysis of Nanosized Al/AlN Powder

The nanosized Al/AlN powder was immersed in deionized water to investigate their hydrolysis behavior from 40 °C to 80 °C. The Al/AlN powder hydrolysis behavior was observed by measuring the pH of the suspension, whereas XRD and TEM analyses were employed for the characterization of the hydrolytic products. The hydrolysis at the higher temperature was different from that at the lower temperature. The nanofibrous crystalline boehmite was formed mainly over 80 °C, while the bayerite (Al (OH3)) coexisted with the boehmite predominantly below 70 °C. The hydrolytic product showed the higher specific surface area at 70 °C than that of the hydrolytic product at other temperatures. The highest specific surface area of hydrolytic product was 145.84m2/g.