| Abstract [eng] |
Nanoparticles are particles with a size of 1-100 nm that are of interest to scientists due to their chemical stability, unique optical properties, and ease of synthesis and functionalization. Nanoparticle-antibody conjugation is an area of research that focuses on the unique properties of nanoparticles and tailoring the specificity of antibodies for various biomedical applications. This work aimed to perform and evaluate the conjugation of quantum dots and gold nanorods with antibodies. CD44 is an observed glycoprotein involved in various physiological and pathological processes, including inflammation, tissue regeneration, and cancer. The nucleocapsid (N) protein of SARS-CoV-2, the virus responsible for the COVID-19 pandemic, is a major component that encapsulates the viral RNA genome. CD44 and SARS-CoV-2 nucleocapsid (N) proteins were successfully immobilized on the surface of a surface plasmon resonance (PPR) sensor chip via an 11-mercapto-undecanoic acid (MUR) self-assembled monolayer (SAM). The surface concentrations of the CD44 marker and the SARS-CoV-2 nucleocapsid (N) protein on the surface of the PPR sensor chip were equal to 2.17 and 4.17 ng/mm2, respectively. Quantum dots modified with polyethylene glycol derivatized with amino groups (KT-NH2) were selected for conjugation with specific antibodies due to lower non-specific interactions with immobilized CD44 protein. The determined size of KT-NH2 was 8.96 ± 0.85 nm and the hydrodynamic diameter was 30.21 ± 1.80 nm. After conjugation with antibodies, the hydrodynamic diameter of the particles increased to 38.09 ± 1.62 nm. Successful conjugation was confirmed by recording the interaction of KT-anti-CD44 conjugates with immobilized CD44 protein. Gold nanorods (AuNS) were also synthesized and their conjugation with secondary antibodies was performed. Conjugation was confirmed by recording the interaction of gold nanorods and antibody conjugates with specific mouse antibodies bound to the immobilized SARS-CoV-2 nucleocapsid (N) protein. Arguably, PPR spectroscopy is a suitable method to evaluate the conjugation of quantum dots and antibodies or gold nanorods and antibodies. |
