This book shelters the central principles, cutting-edge methodologies, and incipient thought processes applied to PEGylation research. The content also expounds on the critical properties of PEG and other polymers that can be applied to formulate a prolonged-circulating nanocarrier system for the delivery of gene, nucleic acid, drugs, protein, and peptide and diagnostic agents. The book summarizes the methodologies and effects of PEGylation on drug delivery and highlights recent developments in PEGylated drugs. It also aims to present vital biopharmaceutical fates of PEGylated therapeutics and examines the approaches involved in the preparation, physicochemical properties, and biological applications of long-circulating PEGylated pharmaceutical nanocarriers. This book also cross-talks and offers expert viewpoints on mucus-penetrating PEGylated nanocarrier, reversible PEGylation of nanocarriers, and Bio-PEGylation as well as PEGylation and its alternatives. The book also deals with hottopics including the current status and regulatory aspects of PEGylated Nanoproducts, and medicinal and pharmaceutical applications of PEGylated Nanocarriers. The book provides a comprehensive literature resource for the students, biologists, chemists, toxicologists, medical researchers, scientists in industries, research institutes, universities, and consultants involved in the development and testing of new advanced medicines