Microstructure and Phase Behavior of Cationic Gemini/Anionic Polyelectrolyte/Water Ternary System

The microstructure of cationic gemini surfactant 1,6-bis(dodecyldimethylammonium) hexane dibromide [C12H25(CH3)2N-(CH2)6-N(CH3)2C12H25×2Br] (12-6-12×2Br-) and oppositely charged polyelectrolyte poly(acrylic acid, sodium salt) (NaPA) in aqueous solution has been studied by using fluorescence, conductivity measurement, freeze-etching and TEM. The data obtained from fluorescence and conductivity measurement show that micelle-like or complex can form between the gemini surfactant (12-6-12×2Br-) and polyelectrolyte NaPA due to the static electric interaction and hydrophobic forces. Through freeze-etching and TEM, the microstructure of the mixture solution has been studied, which is consistent with the result from micropolarity. Comparing the fluorescence spectrum of system of dodecyltrimethylammonium bromide (DTAB) and NaPA with that of system of gemini surfactant (12-6-12×2Br-) and NaPA, it can be found that the interaction between gemini surfactant (12-6-12×2Br-) and NaPA is stronger than that between DTAB and NaPA. And the phase behavior of (12-6-12×2Br-) and NaPA in aqueous solution has also been detected. It can be shown that the precipitate will transform into gel in higher NaPA concentration.     

吡罗克酮乙醇胺盐的蛋白酶抑制作用及与硫酸锌复配的防脱发功效研究（英文）

蛋白水解机制导致棒状末端发根和毛囊之间的细胞粘附分解是头发脱落的最终步骤。在休止期晚期和脱落期，蛋白酶活性的增加导致大量脱发。利用EnzChekTM蛋白酶试剂盒，基于荧光方法检测了吡罗克酮乙醇胺盐在体外对蛋白酶的抑制作用；并对含吡罗克酮乙醇胺盐和硫酸锌的洗发水进行了两组含受脱发困扰的男性和女性参与者的临床防脱发功效测试。结果表明，吡罗克酮乙醇胺盐可以有效抑制蛋白酶的活性，0.5%吡罗克酮乙醇胺盐在体外可使胰蛋白酶的活性减少最高达53%。硫酸锌可以增强低浓度吡罗克酮乙醇胺盐对胰蛋白酶活性的抑制作用。两组临床测试显示，使用含0.5%吡罗克酮乙醇胺盐和0.018%硫酸锌的洗发水4周，8周和12周后，头发密度较使用前均有显著性增加，12周后分别增加2.7根/cm²和7.5根/cm²；较空白对照组，在8周和12周后均有显著性提高。由此提示了吡罗克酮乙醇胺盐对于棒状毛发的保留作用和含吡罗克酮乙醇胺盐和硫酸锌洗发水的防脱发功效。