Meng Lei, Yin Jian-Hang, Yuan Yaqing, Xu Na
College of Materials Science and Engineering, Jilin Institute of Chemical Technology Jilin 132022 China
College of Sciences, Jilin Institute of Chemical Technology Jilin 132022 China.
RSC Adv. 2018 Mar 5;8(17):9327-9333. doi: 10.1039/c8ra00481a. eCollection 2018 Feb 28.
A novel ratiometric fluorescence strategy is developed for specific detection of folic acid (FA) by using 11-mercaptoundecanoic acid protected gold nanoclusters (AuNCs@MUA). In this design, the fluorescence color of the probe can be switched among red, pink, violet and blue by varying the concentration of FA. AuNCs@MUA possesses strong fluorescence peaking at 612 nm (R-signal) and FA exhibits blue emissive auto-fluorescence at 446 nm (B-signal), showing a large emission shift of ∼170 nm. When AuNCs@MUA approaches FA through electrostatic binding, the R-signal decreases while the B-signal increases with titration of FA. Based on the above phenomenon, a radiometric analysis platform is constructed for FA target detection, with a wide linear response range from 0 to 20 μM, and an excellent detection limit of 26 nM. This new ratiometric strategy exhibits low background, and wide signal changes in a low concentration range, which presents obvious advantages over most previous FA detections based on single-responsive fluorescence methods. Furthermore, the proposed method is successfully applied to determine FA in human serum samples.
通过使用11-巯基十一烷酸保护的金纳米簇（AuNCs@MUA），开发了一种用于特异性检测叶酸（FA）的新型比率荧光策略。在该设计中，通过改变FA的浓度，探针的荧光颜色可在红色、粉色、紫色和蓝色之间切换。AuNCs@MUA在612 nm处有强荧光峰（R信号），而FA在446 nm处呈现蓝色发射自荧光（B信号），发射位移约为170 nm。当AuNCs@MUA通过静电结合接近FA时，随着FA的滴定，R信号降低而B信号增加。基于上述现象，构建了用于FA目标检测的比率分析平台，线性响应范围宽，从0到20 μM，检测限低至26 nM。这种新的比率策略背景低，在低浓度范围内信号变化大，与大多数以前基于单响应荧光方法的FA检测相比具有明显优势。此外，该方法成功应用于测定人血清样品中的FA。
