Metal phenolic networks (MPNs)-based pH-sensitive stimulus responsive nanosystems for drug delivery in tumor microenvironment

The tumor microenvironment (TME) is a dynamic and complex system characterized by different cellular, mo-lecular, and physiological heterogeneity. Therefore, conventional drug delivery strategies often failed to deliver an effective dosage to kill cancerous cells. In recent years, the development of nano-based drug delivery has expanded into a wide range of clinical applications to address the limitations of free therapeutics and voyage the biological barriers. Recently, stimuli-responsive metal phenolic networks (MPNs) have recently become a focus of intense scientific investigation in biomedical applications, and offer a versatile platform for controlled release of therapeutics in TME. This review provides a timely and thorough description of the use of a MPNs in the rapidly evolving field of advanced drug delivery with insights unique to pH-stimulus responsive systems. This review aims to offer an in-depth understanding of the potential use of MPNs as pH-sensitive therapeutics carriers in TME. We briefly explained the endogenous pH-associated factors affecting the therapeutics delivery in TME. A cross comparison of the advantages and disadvantages of MPNs with other counterparts are highlighted to elucidate their key design principles for pH-stimulus responsive drug delivery in TME. In later sections, pros and cons of MPNs as well as current challenges and future perspectives are also discussed, which will deepen our understanding of designing, fabricating, and applying MPNs for advanced therapeutics.