Nanoparticles, defined as particulate systems with dimensions ranging from 10- 1000nm, have emerged as highly versatile carriers for drug delivery, diagnostics, and therapeutic applications. Depending on their structural design, nanoparticles can exist as nanospheres- where drugs are uniformly dispersed within the matrix – or nano capsules, where drugs are confined within a polymeric cavity surrounded by a membrane. Advances in biodegradable polymeric nanoparticles, particularly those coated with hydrophilic polymers such as polyethylene glycol (PEG), have enabled prolonged circulation, site- specific targeting, and improved delivery of proteins, peptides, nucleic acids, and chemotherapeutic agents. Their preparation involves diverse methods including emulsion – solvent evaporation, double emulsion, salting out, solvent displacement, and diffusion techniques, each influencing particle size, zeta potential, morphology, crystallinity, entrapment efficiency, and in vitro release studies are critical for ensuring reproducibility and therapeutic efficacy. Nanoparticles find extensive applications across biomedical and pharmaceutical domains, including tumour targeting via passive and active mechanisms, oral and ocular drug delivery, dermatology, pulmonary delivery, gene therapy, molecular diagnostics, and biosensor. Their ability to enhance solubility, protect liable drugs from degradation, and provide sustained or controlled release make them attractive alternatives to conventional dosage forms. However, challenges such as physical instability, reactivity, aggregation, burst release, and limit drug loading remain. Moreover, nanoparticles high reactivity in cellular environments raises safety and stability concerns and further optimization of formulation strategies and materials.
Mr. A. Yuvan Shankar*, Mrs. Sujitha M.1, Rahul R.2, Vaishali K.2, Vigneshwar D.2, Vimala S.2, Yuvanshankar A.2 (Sun,) studied this question.