Shanxi Normal University, Taiyuan 030031, PR China.
Shanxi Normal University, Taiyuan 030031, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2022 Nov 5;280:121497. doi: 10.1016/j.saa.2022.121497. Epub 2022 Jun 15.
We successfully designed an aptasensor based on the red emission carbon dots (R-CDs) and effectively detected insulin (INS) via fluorescence resonance energy transfer (FRET). In the process, the aptamer (apt) labeled with R-CDs (R-CDs@apt) was used as fluorescence donor and graphene oxide (GO) was used as fluorescence receptor. The successful detection due to the aptamer sequence has a certain affinity for Go and INS, while the affinity for INS is stronger than that of GO. When INS is not added to the detection system, the aptamer is adsorbed onto the surface of GO, shortening the distance between R-CDs@apt and GO, resulting in FRET and the quenching of fluorescence of R-CDs@apt. When INS was added to the detection system, the aptamer selectively bound INS and separated from the adsorption of GO, FRET gradually disappeared and the fluorescence of R-CDs@apt/GO/INS system was restored. By comparing the changes of fluorescence intensity before and after adding INS, the detection of INS was implemented. The aptasensor has a good linear curve with the detection limit of as low as 1.1 nM when the concentration of INS reached 1.3-150 nM. This method has excellent selectivity and anti-interference. Therefore, it is a potential method for detecting substances in biological fluids.
我们成功设计了一种基于红色发射碳点（R-CDs）的适体传感器，并通过荧光共振能量转移（FRET）有效地检测了胰岛素（INS）。在该过程中，被标记有 R-CDs（R-CDs@apt）的适体（apt）被用作荧光供体，而氧化石墨烯（GO）被用作荧光受体。成功检测的原因是适体序列对 GO 和 INS 具有一定的亲和力，而对 INS 的亲和力强于 GO。当 INS 未添加到检测系统中时，适体被吸附到 GO 的表面上，缩短了 R-CDs@apt 和 GO 之间的距离，导致 FRET 和 R-CDs@apt 的荧光猝灭。当 INS 添加到检测系统中时，适体选择性地结合 INS 并与 GO 的吸附分离，FRET 逐渐消失，R-CDs@apt/GO/INS 体系的荧光恢复。通过比较添加 INS 前后荧光强度的变化，实现了对 INS 的检测。当 INS 的浓度达到 1.3-150 nM 时，适体传感器具有良好的线性曲线，检测限低至 1.1 nM。该方法具有出色的选择性和抗干扰性。因此，它是一种用于检测生物流体中物质的潜在方法。
