Fluorescence Masking Based Multifunctional Quantum Dots’ Assay for HSP90α Interactions Detection

• Published in: Applied sciences Vol. 13; no. 5; p. 2957
• Main Authors: Kishore, Anusha, Fan, Lu, Stahl, Frank, Reichel, Thomas, Krüger, Karsten, Zeilinger, Carsten
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.03.2023
• Subjects: Antibodies; Assaying; Biological properties; Biological samples; Biosensors; biotin-ATP; biotin-HSP90 antibody; Cellulose esters; Cellulose nitrate; Chemical compounds; Dyes; Ethylenediaminetetraacetic acid; Fluorescence; fluorescence masking; Fluorophores; Graphene; Heat shock proteins; HSP90α; Ligands; Masking; Nanocrystals; Physical stress; Protein interaction; Proteins; Quantum dots; Sav-QD; Streptavidin; Stress proteins; Germany
• ISSN: 2076-3417; 2076-3417
• DOI: 10.3390/app13052957

HSP90α is one of the most common stress proteins in cells; hence, it is a good target for developing drugs and testing systems for cancer or physical stress levels in humans. Streptavidin conjugated quantum dots (Sav-QDs) are widely used as fluorophores for biosensing to overcome chemical labelling problems. In this work, we have attempted to develop a multifunctional and robust assay for HSP90α. The detection technique was based on the masking of the fluorescence of spotted Sav-QDs on nitrocellulose chips (NC). Biotinylated ligand/antibody attaches to the spotted Sav-QD and then HSP90α is attached, which causes the masking of fluorescence. The masking of fluorescence was used to detect protein–ligand interactions, the effect of inhibitors, protein–protein interactions, and the presence of protein in the biological sample. The load of detection (LoD) of the assay lies in the nano molar range, making it a sensitive assay. The results from the experiments suggest that the used approach is promising for developing a multifunctional, robust, and sensitive assay for proteins that can be used for point-of-care detection in complex biological samples.