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We present here a facile synthesis of SO 2- ₄/ZrO₂ solid superacid by impregnating the biscuit-like mesoporous ZrO₂ nanoparticles prepared by an emulsion combustion method directly into H₂SO₄ solution. The obtained solid acid catalyst was characterized by means of X-ray powder diffraction, transmission and scanning electron microscopy, thermogravimetry, Brunner-Emmet-Teller measurement, and infrared analysis. Its catalytic performance was examined by alkylation of o -xylene with styrene. The optimal catalytic formulation, obtained from the investigation of experimental conditions, was determined to be 5 wt% of catalyst loading with initial o -xylene/styrene molar ratio of 5 under reaction temperature at 120 °C for 120 min, achieving a 100% styrene conversion and a 93.3% 1-phenyl-1-xylyl ethane selectivity. The biscuit-like SO 2- ₄/ZrO₂ solid acid exhibited high catalytic activity and selectivity and excellent structural stability. This synthetic strategy for preparing the mesoporous SO 2- ₄ promoted ZrO₂ solid superacid catalyst is generalized and expected to be applied to other metal oxides.

The doxorubicin hydrochloride (DOX)-loaded poly(L-lactic acid)/hydroxyapatite/gelatin (PLLA/a-HA/gelatin) particle was prepared by emulsion/solvent evaporation method using CH2Cl2 as a solvent. HA nanoparticles were prepared via a facile chemical precipitate method and HA nanoparticles were functionalized by adding aminopropyltriethoxysilane (APTS) under microwave radiation. The physical and chemical properties of HA and modified HA were characterized by XRD, TEM, FT-IR, and XPS. Furthermore, the release of DOX from PLLA/a-HA/gelatin was also estimated. Results indicated that HA was successfully functionalized via APTS and functionalized HA has primary amino groups on its surface which improved the surface chemical compatibility between HA and PLLA matrix. The prepared PLLA/a-HA/gelatin was considered as a drug release carrier to study sustained release behavior of doxorubicin hydrochloride (DOX). The PLLA/a-HA/gelatin can effectively prolong the release time of DOX and exhibits a stable and sustainable drug release which indicates that the PLLA/a-HA/gelatin nanocomposite material could serve as a potential carrier for novel drug release system.