Latex beads, carboxylate-modified polystyrene, are widely used in biomedical research and diagnostics. They serve as essential tools in immunoassays, where they act as solid supports for the immobilization of antibodies or antigens, enhancing the sensitivity and specificity of detection methods like ELISA. These beads are also employed in flow cytometry for cell sorting and analysis, as they can be conjugated with fluorescent markers or biomolecules to target specific cell populations. In addition, they are utilized in the development of biosensors, where their surface modification allows for the attachment of biorecognition elements. Furthermore, these beads play a role in drug delivery systems, enabling the controlled release of therapeutic agents. Their uniform size and surface properties make them ideal for calibration standards in particle size analysis and instrument validation.