温度对SiO_2气凝胶表面疏水官能团数量及疏水性的影响

SiO_2气凝胶颗粒多采用表面修饰甲基官能团的方法进行疏水改性。该方法存在受热后疏水官能团断裂,疏水性下降的问题。目前官能团数量及疏水性随温度及加热时间的变化规律以及官能团数量与接触角之间的关系尚不明确。采用三甲基氯硅烷对SiO_2进行疏水改性。利用傅里叶红外光谱和接触角测试方法分析了疏水SiO_2气凝胶表面甲基官能团数量及疏水性随温度、加热时间的变化规律,在此基础上明确了接触角与官能团数量之间的关系。结果表明:提高受热温度及加热时间均会使疏水SiO_2气凝胶颗粒表面甲基官能团数量变小,进而降低静态接触角。当温度达到600℃时,甲基官能团完全消失,材料失去疏水能力。材料接触角与表面甲基官能团损失量近似呈正比关系。

Microfluidic Immunoprecipitation for Post-Translational Modified Protein Purification

In this paper, we report an antibody functionalized microimmunopreci- pitation （IX IP） method used for enrich lowabundant post-translational modified （PT~ proteins. The device is fabricated by inert, nontoxic and disposable polydimethylsiloxane （PDMS） using a silane-based chemical modification protocol, which yield antibody- terminated PDMS surfaces. In this study, the IX IP device is specifically designed for the purification of carbonylated protein, a representative example here to illustrate the potential applications for any other PTMs, which could be immuno-tagged by specific antibodies. The test model in vitro oxidized bovine serum albumin （BSA） was first derivitized by dinitrophenylhydrazide （DNPH） and then captured by the anti-DNP immobilized on this Ix lP device. The surface functional group mapping was systematically analyzed and validated by fluorescence microscopy. Quantitative study of DNP-derivatized carbonylated protein capture recovery and elution efficiency of the device was also studied. We also envision that this proteome enrichment Ix IP device can be assembled with other lab-on-a-chip components, such as microelectrophoresis or micro-chromatographic devices for follow-up protein analysis. This selective enrichment of modified proteins greatly facilitates the study of low abundant protein biomarkers discovery.

单氟甲基化反应的研究进展

有机氟化物在医药、农业化学等领域发挥着不可缺少的作用,其中,氟甲基官能团具有较强的的亲脂性,可以极大地改善药物分子的药代动力学性质.因此,开发各类氟化反应具有重要的价值,尤其向分子中引入单氟甲基在氟化学领域备受关注.针对不同结构分子的单氟甲基化,按照氟甲基试剂分类总结单氟甲基化反应的研究进展,并对部分反应可能的机理进行讨论.