原位还原的金纳米簇抑制β乳球蛋白淀粉样纤维形成

Inhibition Effect of In-Situ Reduced Gold Nanoclusters on the Formation of ?-Lactoglobulin Amyloid Fibrils

在碱性条件下,以β乳球蛋白(β-LG)为还原剂,直接原位还原氯金酸制备了荧光金纳米簇.通过调控氯金酸的用量,获得了红色和黄色两种荧光金纳米簇,并对其光学性质和形貌进行了表征.进一步,利用荧光光谱、圆二色光谱、动态光散射和透射电子显微镜等分析手段系统考察了这两种金纳米簇对β-LG聚集的抑制作用.研究发现:在这两种体系中,被吸附在金纳米簇表面的β-LG蛋白量不同,导致其对β-LG聚集的抑制作用也不同,即红色荧光金纳米簇可抑制β乳球蛋白聚集生长期,而黄色荧光金纳米簇则可抑制其成核期.

A facile and efficient method was developed for preparing fluorescent gold nanoclusters(AuNCs)via insitureduction of chloroauric acid by β-lactoglobulin(β-LG)under alkali condition. We further characterized the opticaland morphological properties of the resulting red and yellow fluorescent AuNCs,which were prepared with differentloadings of chloroauric acid. In addition,the inhibition effect of these nanoclusters on the aggregation of β-LG wasinvestigated using several spectroscopy and microscopy techniques,such as fluorescence spectroscopy,circulardichroism spectroscopy,dynamic light scattering,and high resolution transmission electron microscopy. The resultsindicate that different contents of proteins are adsorbed onto these two kinds of gold nanoclusters. The red fluorescentAuNCs are found to inhibit the growth of β-LG amyloid fibrils,whereas the yellow one can inhibit the nucleation ofβ-LG.