Analytical Techniques for Characterizing Tumor-Targeted Antibody-Functionalized Nanoparticles

The specific interaction between cell surface receptors and corresponding antibodies has driven opportunities for developing targeted cancer therapies using nanoparticle systems. It is challenging to design and develop such targeted nanomedicines using antibody ligands, as the final nanoconjugate's specificity hinges on the cohesive functioning of its components. The multicomponent nature of antibody-conjugated nanoparticles also complicates the characterization process. Regardless of the type of nanoparticle, it is essential to perform physicochemical characterization to establish a solid foundation of knowledge and develop suitable preclinical studies. A meaningful physicochemical evaluation of antibody-conjugated nanoparticles should include determining the quantity and orientation of the antibodies, confirming the antibodies' integrity following attachment, and assessing the immunoreactivity of the obtained nanoconjugates. In this review, the authors describe the various techniques (electrophoresis, spectroscopy, colorimetric assays, immunoassays, etc.) used to analyze the physicochemical properties of nanoparticles functionalized with antibodies and discuss the main results.