State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, PR China.
State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, PR China.
Talanta. 2017 Nov 1;174:797-802. doi: 10.1016/j.talanta.2017.07.013. Epub 2017 Jul 1.
Trypsin and its inhibitors are relevant to many physiological processes and diseases. In this study, a nanosensor capable of detecting trypsin and its inhibitors was designed based on the fluorescence resonance energy transfer (FRET) between upconversion nanoparticle (UCNP) and gold nanoparticle (AuNP). UCNP and AuNP were linked by a trypsin-sensitive peptide DDDDARC, forming the non-fluorescent UCNP-peptide-AuNP nanosensor. In the presence of trypsin, the peptide was cleaved and the quenched fluorescence was restored; in the presence of trypsin inhibitors, the recovery of the fluorescence was decreased. The nanosensor showed a superb sensitivity and selectivity for trypsin and its inhibitors, with a detection limit of 4.15ngmL for trypsin. UCNP-peptide-AuNP could eliminate the interference of background fluorescence and avoid the light toxicity, and potentially be used to diagnose trypsin-related diseases or screen trypsin inhibitors.
胰蛋白酶及其抑制剂与许多生理过程和疾病有关。在这项研究中，设计了一种基于上转换纳米粒子（UCNP）和金纳米粒子（AuNP）之间荧光共振能量转移（FRET）的纳米传感器，用于检测胰蛋白酶及其抑制剂。UCNP 和 AuNP 通过胰蛋白酶敏感肽 DDDDARC 连接，形成非荧光 UCNP-肽-AuNP 纳米传感器。在存在胰蛋白酶的情况下，肽被切割，荧光被恢复；在存在胰蛋白酶抑制剂的情况下，荧光的恢复程度降低。该纳米传感器对胰蛋白酶及其抑制剂具有出色的灵敏度和选择性，检测胰蛋白酶的检出限为 4.15ngmL。UCNP-肽-AuNP 可以消除背景荧光的干扰并避免光毒性，有潜力用于诊断与胰蛋白酶相关的疾病或筛选胰蛋白酶抑制剂。
