Superoxide Dismutase Detection on Silver Nanostructured Substrates through Surface-Enhanced Spectroscopic Techniques

Autor: Anastasia Kanioura, Georgia Geka, Ioannis Kochylas, Vlassis Likodimos, Spiros Gardelis, Anastasios Dimitriou, Nikolaos Papanikolaou, Sotirios Kakabakos, Panagiota Petrou
Jazyk: angličtina
Rok vydání: 2024
Předmět:
Zdroj: Chemosensors, Vol 12, Iss 6, p 89 (2024)
Druh dokumentu: article
ISSN: 12060089
2227-9040
DOI: 10.3390/chemosensors12060089
Popis: Oxidative stress refers to the overproduction of reactive oxygen species and is often associated with numerous pathological conditions. Superoxide dismutase (SOD) is a widely used enzyme for evaluating oxidative stress, with numerous methods being developed for its detection in biological specimens like blood, urine, and saliva. In this study, a simple metal-assisted chemical etching method was employed for the fabrication of nanostructured silicon surfaces decorated with either silver dendrites or silver aggregates. Those surfaces were used as substrates for the immunochemical determination of SOD in synthetic saliva through surface-enhanced Raman spectroscopy (SERS) and surface-enhanced fluorescence (SEF). The immunoassay was based on a 3-step competitive assay format, which included, after the immunoreaction with the specific anti-SOD antibody, a reaction with a biotinylated secondary antibody and streptavidin. Streptavidin labeled with peroxidase was used in combination with a precipitating tetramethylbenzidine substrate for detection through SERS, whereas for SEF measurements, streptavidin labeled with the fluorescent dye Rhodamine Red-X was utilized. Both immunoassays were sensitive, with a detection limit of 0.01 μg/mL and a linear dynamic range from 0.03 to 3.3 μg/mL, enabling the evaluation of the oxidative stress status of an organism.
Databáze: Directory of Open Access Journals