Drug delivery and functional nanoparticles

An optimal drug-delivery formulation should be biocompatible, specific to the target site, avoid enzymatic degradation, provide optimal drug loading and release, and be cost-effective. The nanomaterials, with their small size, unique physicochemical characteristics, and diverse therapeutic potential, have shown a lot of promise in the past decade. In this chapter, the authors provide a comprehensive summary of the common state-of-the-art nanoparticle (NP)-based approaches currently being considered for clinical applications. NPs can overcome the limitations of existing therapies and biological barriers (systemic, microenvironmental, and cellular); especially the latter that accounts for the heterogeneity in patient populations. Broadly, nanoparticles may be organic or inorganic. The organic nanoparticles include liposomes, micelles, dendrimers, and polymer-based, while the inorganic group can be classified into gold, silica, carbon nanotubes, and quantum dots. NP-based therapies have been extensively studied in various diseases, especially in cancer. Some NP-based delivery systems against cancer are already approved by the Food and Drug Administration (FDA) for drugs such as Taxol, Carboplatin, and Cerubidine. The knowledge of this field is still limited regarding the interactions between nanomaterials and the immune system. There have been potentially fruitful findings, but they mostly have been experimental. Cellular origin, drug loading, and target specificity have to be extensively studied before they can be broadly employed in tumor therapy as the next generation of nanomaterials. One major limitation of using lipid nanoparticles for drug delivery is the scarcity. How the excipient itself is metabolized or excreted is also currently an area of investigation. The unknown health hazards and toxic effects and the absence of proper regulatory protocols are the primary roadblocks in the practical application of NPs. The complexity of many diseases as well as particular tissues such as the brain require multidisciplinary team efforts.