Abstract. The present study aims to prepare carvedilol (CAR) nanosuspensions using the anti-solvent precipitation-ultrasonication technique to improve its dissolution rate and oral bioavailability. Alphatocopherol succinate (VES) was first used as a co-stabilizer to enhance the stability of the nanosuspensions. The effects of the process parameters on particle size of the nanosuspensions were investigated. The optimal values of the precipitation temperature, power inputs, and the time length of ultrasonication were selected as 10°C, 400 W, and 15 min, respectively. Response surface methodology based on central composite design was utilized to evaluate the formulation factors that affect the size of nanosuspensions, i.e., the concentration of CAR and VES in the organic solution, and the level of sodium dodecyl sulfate in the antisolvent phase, respectively. The optimized formulation showed a mean size of 212±12 nm and a zeta potential of −42±3 mV. Scanning electron microscopy revealed that the nanosuspensions were flaky-shaped. Powder Xray diffraction and differential scanning calorimetry analysis confirmed that the nanoparticles were in the amorphous state. Fourier transform infrared analysis demonstrated that the reaction between CAR and VES is probably due to hydrogen bonding. The nanosuspension was physically stable at 25°C for 1 week, which allows it to be further processing such as drying. The dissolution rate of the nanosuspensions was markedly enhanced by reducing the size. The in vivo test demonstrated that the C max and AUC 0-36 values of nanosuspensions were approximately 3.3-and 2.9-fold greater than that of the commercial tablets, respectively.

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Photodynamic therapy (PDT) has been regarded as a promising strategy for tumor therapy. However, heterogeneous tumor microenvironment severely limits the efficacy of photodynamic therapy. In this work, a multifunctional theranostic...

This study suggested the potential of proniosomes as stable precursors for the immediate preparation of niosome carrier systems.

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One bacterial strain was isolated from a Panax notoginseng field and identified as Bacillus subtilis C2 by its physiological and biochemical characteristics. The culture filtrate of the bacterium showed strong antifungal activity against Trichoderma harzianum and Gliocladium roseum. The antifungal compound termed 10M was purified from the culture filtrates of B. subtilis C2 through organic solvent extraction, silica gel H and Sephadex LH-20 column chromatography. Chlamydospores were formed either inside the conidia or from hyphae, when the conidia of T. harzianum and G. roseum were cultured on the surface of the potato dextrose agar (PDA) containing relatively low concentrations of 10M for 48 h. While they were cultured on the surface of PDA containing relatively high concentrations of 10M for 48 h the cells were swollen and then lysed. The 10M had high similarity to iturin A as showed by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry. This is the first report that antifungal compounds produced by B. subtilis can induce chlamydospore formation in biocontrol fungi at relatively low concentrations.

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