Abstract:: Cancer is the most malignant chronic disease worldwide, with a high mortality rate. It can be treated with conventional therapies such as chemotherapy and immunotherapy, but these techniques have several side effects, limiting their therapeutic outcome and reducing application. Recently, a promising method of drug delivery has been devised to minimize side effects and induce potential benefits during treatment. The targeted drug delivery system (TDDS) is one of the established drug delivery methods using nanoparticles, crossing different biological barriers, targeting a specific diseased site, and resulting in sustained drug release. The current research introduces a plethora of nanoparticles that can be implemented to deliver or target drugs to a particular site, such as polymeric nanoparticles (PLGA, PLA, chitosan), metal-based nanoparticles (gold, iron oxide), carbon-based nanoparticles (CNTs, graphene), bio nanoparticles (liposomes, micelles) and ceramic nanoparticles (mesoporous-based silica, calcium phosphate). Most of them are proven to be very efficient in targeting the desired site and causing fatal damage to the tumor cells. Zinc oxide (ZnO) is a nano compound, that shows a wide range of favorable properties, making it widely acceptable for biomedical applications. This review focuses on TDDS using ZnO as a drug carrier, followed by factors affecting TDDS such as drug loading, encapsulation efficiency, cell viability, and zeta potential. The target mechanism of TDDS for cancer therapy has also been discussed, indicating a better alternative for clinical treatment. This approach also presents certain challenges besides the potential for oncology.

The present work focuses on the growth of ZnO films vertically on indium tin oxide substrate using a wet chemical method. The morphological and structural study of the prepared films confirmed the formation of one-dimensional growth with a polycrystalline single-phase hexagonal wurtzite structure. The computed texture coefficient indicates the c-axis growth of the film. The optical spectra study exhibited a strong and sharp characteristics absorption band. The numerical derivative method and the Tauc plot method for the different transition values have been used to compare energy bandgap calculations.