Quality by Design (QbD) is a systematic approach to development that begins with predefined objectives for a product, process understanding, and process control based on knowledge and quality risk management. All conventional methods may fail to the intended purpose during method development and validation. In a QbD approach, the impact and interactions between critical method variables are understood using a Design of Experiments (DOE) approach, which gives multivariate analysis and modeling leading to the consistent quality of drug products. QbD tools like risk assessment and design of experiments, enable better quality to be incorporated into the analytical method and facilitate prior understanding and identification of variables affecting method performance. The main objective of the present review article is to describe different steps involved in method development by the QbD approach for analytical method development. The QbD Approach for method development comprises various steps that include defining method intent, performing experimental design, evaluating experimental results, selecting proper method conditions, and performing risk assessment with changing analytical parameters and conditions for evaluation. The purpose of analytical QbD is to attain quality in measurement. Keywords: Quality by Design (QbD), Design of Experiments (DOE), Critical attributes

Quantum dots (QDs) are nanoparticles that have been developed for a number of biological and biomedical applications, such as drug delivery and simultaneous imaging of several cells. As a result of their unique physicochemical features, QDs have shown remarkable potential in receptor-based targeting. Functionalized QDs (f-QDs) are nano-sized smart systems that can deliver a wide spectrum of bioactive. Surface modified fluorescent carbon QDs has received interest as a targeting ligand for achieving cellular targeting with increased specificity. Several surface-designed and conjugated fluorescent carbon QDs are currently being investigated for cancer treatment, and the results are awaited with bated breath. This review emphasizes different synthesis methods, their characterizations, and different applications of QDs in cancer therapies. Keywords: Quantum dots, Synthesis, Medical applications.