Ratiometric ECL sensor based on Apt-AuNS@Lu nanoprobe for analyzing cell swelling-induced ATP release

• Published in: Mikrochimica acta (1966) 2022-11, Vol.189 (11), p.423-423, Article 423
• Main Authors: Zhou, Fan, Xiao, Mingxing, Feng, Defen, Yang, Peihui
• Format: Article
• Language: English
• Subjects: Analytical Chemistry; Catalytic activity; Characterization and Evaluation of Materials; Chemical tests and reagents; Chemistry; Chemistry and Materials Science; Electric properties; Electrochemiluminescence; Electron transfer; Graphene; Indium; Indium tin oxides; Microengineering; Nanochemistry; Nanocomposites; Nanotechnology; Original Paper; Potassium persulfate; Product introduction; Surface stability
• ISSN: 0026-3672; 1436-5073
• DOI: 10.1007/s00604-022-05491-3

A novel ratiometric electrochemiluminescence (ECL) system based on gold nanostars (AuNSs) support was constructed for the determination of hypotonicity-induced ATP release from HepG2 cells. AuNS@Lu nanoprobe was used as anodic luminophore and K 2 S 2 O 8 as cathodic luminophore as well as anodic co-reactant. AuNS with the large specific surface was adopted to adsorb plentiful luminol to form solid-state probe and as affinity support to immobilize ATP aptamer (Apt). The obtained nanocomposite (Apt-AuNS@Lu) generated a strong ECL signal at + 0.4 V (vs . Ag/AgCl ) with co-reactant K 2 S 2 O 8 , because of excellent conductivity and catalytic activity of AuNS. Furthermore, graphene oxide was reduced onto indium tin oxide (ITO) electrodes to facilitate the electron transfer. Following, polydopamine (PDA) film was formed via self-polymerization, improving stability and adhesion of the electrode surface. To immobilize ATP capture aptamer (Apt C ), abounding AuNSs were attached to RGO/PDA surface. When the sensor was incubated in the mixture solution of Apt-AuNS@Lu and target ATP, the ECL signal of Apt-AuNS@Lu increased with the increase of ATP concentration, meanwhile, the signal of K 2 S 2 O 8 declined. The ratio of the two luminophores was used for the quantitative determination of ATP. The linear range was 5 to 250 nM, and the limit of detection was 1.4 nM at (3σ)/S. The method was successfully applied to analyze ATP release from HepG2 cells stimulated by 0.45% NaCl hypotonic solution. The results showed that the release kinetics profile of ATP had a sigmoidal shape with rapid release within 10 min and then slowed. Compared to the isotonic groups, the intracellular ATP concentration was 3.7 ± 0.3 µM ( n  = 3) decreasing by 40.3% and the extracellular was 23.4 ± 1.2 nM ( n  = 3) increasing by 9.2 times in the hypotonicity for 10 min, which showed ATP release from cells and good agreement with commercial ELISA test. The proposed strategy would be beneficial to broadening application of ECL technology in studying cell biological functions. Graphical abstract