肝靶向荧光探针用于HepG2细胞中ONOO^(−)的特异性检测

Liver-Targeted Fluorescent Probes for Specific Detection of ONOO-in HepG2 Cells

过氧亚硝酸根(ONOO^(-))作为重要的生物活性分子,在细胞信号转导和稳态调节等过程中发挥着重要的作用。实现生物体ONOO的精准靶向检测,对于深入探索其生理病理机制至关重要。本文以1,8-萘二甲酰亚胺作为荧光发色团、熊去氧胆酸作为肝靶向单元,制备荧光探针N-丙基-4(-4-3α,7β-二羟基-5β-胆甾烷-24-酰肼基)-1,8-萘二甲酰胺(NA),用于人肝癌细胞(HepG2)中ONOO的特异性检测。该探针与ONOO响应后,其绿色荧光显著增强,且荧光强度与ONOO浓度在0~14.0μmol/L范围内呈现较好的线性关系,检测限为0.27μmol/L。该探针具有选择性强、受pH环境影响小和生物相容性好等优点。细胞荧光成像结果表明,该探针对肝癌细胞HepG2具有较好的靶向性,可以对HepG2细胞中外源性和内源性ONOO浓度进行特异性检测。

As an important biologically active molecule,peroxynitrite(ONOO^(-))plays an important role in cellular signal transduction and homeostatic regulation.Precise and targeted detection of ONOO^(-)in biological systems is crucial for in-depth exploration of its physiological and pathological mechanisms.A“turn-on”fluorescent probe naphthalamide derivative(NA)is designed based on 1,8-naphthalene imide and ursodeoxycholic acid for specific detection of ONOO^(-)in HepG2 cells.Probe NA is synthesized by three steps,the structures of intermediates and target compounds are confirmed by 1 H NMR and 13C NMR spectroscopy and HRMS.The optical properties of probe NA are explored.The green fluorescence of probe NA in the presence of ONOO^(-)is significantly increased compared to its fluorescence in the absence of ONOO^(-).The fluorescence intensity and concentrations of ONOO^(-)shows a good linear relationship in the range of 0.0 to 14.0μmol/L,with the detection limit of 0.27μmol/L.In addition,probe NA shows excellent selectivity toward ONOO^(-),good biocompatibility,and the fluorescence intensity is almost independent to the pH of the environment.Finally,probe NA is applied to monitor ONOO^(-)in living cells.The results of cell fluorescence imaging exhibit that probe NA possesses good targeting ability to HepG2 cells,and can detect exogenous and endogenous ONOOin HepG2 cells,which demonstrates the great potential of in the application of ONOO^(-)detection in vivo.