Magnetic Rolling Circle Amplification-Assisted Single-Particle Collision Immunosensor for Ultrasensitive Detection of Cardiac Troponin I.
Anal Chem
; 94(36): 12514-12522, 2022 09 13.
Article
em En
| MEDLINE
| ID: mdl-36049116
ABSTRACT
Owing to its simplicity, high throughput, and ultrasensitivity, single-particle collision electrochemistry (SPCE) has attracted great attention in biosensing, especially labeled SPCE. However, the low signal conversion efficiency and much interference from complex samples limit its wide application. Here, a new and robust SPCE immunosensor was proposed for ultrasensitive cardiac troponin I (cTnI) detection by combining target-driven rolling circle amplification (RCA) with magnetic beads (MBs). Antibody-modified MBs have good stability, dispersity, and magnetic response capacity in complex samples, enabling efficient capture and separation of cTnI with high specificity and anti-interference ability. The presence of cTnI could specifically drive the formation of magnetic immunocomplexes followed by triggering RCA and enzyme digestion reaction. By using Pt nanoparticles (Pt NPs)-modified ssDNA as signal probes, one cTnI molecule could induce the release of 4.5 × 104 Pt NPs for collision experiments, greatly enhancing signal conversion efficiency and detection sensitivity. Based on the integration of MBs with RCA, the SPCE immunosensor realized 0.57 fg/mL cTnI detection with a wide linear range of 1 fg/mL to 50 ng/mL. Furthermore, cTnI detection in serum samples of myocardial infarction patients was successfully performed, demonstrating great application prospect of the SPCE immunosensor in clinical diagnosis.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Técnicas Biossensoriais
/
Nanopartículas Metálicas
Tipo de estudo:
Diagnostic_studies
Limite:
Humans
Idioma:
En
Revista:
Anal Chem
Ano de publicação:
2022
Tipo de documento:
Article