Used in targeted drug delivery systems to enhance the specificity of therapeutic agents toward cancer cells. The folic acid (FA) component binds to folate receptors, which are overexpressed on many tumor cells, enabling selective cellular uptake. The NH2-PEG segment improves solubility, prolongs circulation time in the bloodstream, and reduces immune recognition. Commonly employed in the development of nanoparticle-based carriers, antibody conjugates, and diagnostic imaging probes. Also utilized in bioconjugation processes where controlled linkage between biomolecules and functional moieties is required.