General Methods for Generation, Characterization, and Functionalization of Different Types of Nanomaterials

Nanotechnology has proved its worth in diverse scientific arenas, which include but are not limited to nano-vaccines and adjuvants facilitating prophylaxis; nanosensors, biomedical devices, and imaging modalities assisting in state-of-the-art diagnostics; antimicrobials; targeted nano-delivery systems; photothermal therapy enabling cutting-edge therapeutics or theranostics; wound and fracture management; and cosmetics. Myriads of engineered nano-delivery systems possessing several novel attributes provide unique benefits, such as enhanced and specific penetration, crossing the physiological barriers, facilitating targeted drug delivery, and preventing rapid degradation and clearance of the encapsulated drugs, precisely delivering gene or si-RNAs or biologicals. Further, nano-formulations can exert synergistic action or even act itself as drugs to overcome tricky situations like drug resistance or tolerance. The nanoscale materials of 1–10 nm size at least in one dimension are having narrow size distribution, a high surface area-to-volume ratio, enormous scope of surface functionalization, and unique optical, electrical, and magnetic properties which render them suitable for multi-arrayed biomedical applications. Nanomaterials can be synthesized either by top-down or bottom-up approach. In top-down approach, the bulk material is broken down into sub-micronic particles by applying chemical, physical, and biological energy. In bottom-up approach, the nanomaterials are synthesized from their atomic-level counterparts using various chemical or biological methods. Characterization of the synthesized nanomaterials is essential to verify their physicochemical attributes, which may be performed using diverse spectroscopic, X-ray-based, magnetometric, or microscopic techniques, such as X-ray diffraction, FTIR, NMR, UV-visible spectroscopy, DLS, mass spectrometry, superconducting quantum interference device magnetometry, TEM, SEM, and measurement of zeta potential. Functionalization modifies the surface chemistry of nanoparticles by the addition of new properties or features such as ligand molecules, polymers, and biomolecules through covalent or non-covalent interactions. Functionalization enhances the biocompatibility, bioimaging potential, drug targeting and sustained release, intracellular delivery, and theranostic applications of the nanomaterials.