**Abstract**

Nanoparticles synthesized from noble metals have wide applications in therapeutics and medicine due to their excellent properties. Properties such as surface plasmon resonance, low toxicity, biocompatibility, and ease of surface modification account for the recent surge in nanoscience and technology. Noble metals such as gold, silver, copper, iron, and platinum with nano size are well-known metallic nanoparticles with increasing applications in nanomedicine. Biomedical applications of these particles especially for diagnosis and targeted drug delivery in living systems require considering the toxicity level. Because of their surface electrons, metal ions in solution affect cellular activities via cell division, apoptosis, DNA replication, homeostasis etc. They influence cell viability through metabolic outputs in both desired and undesired paths which may result in chemical and or biological toxicity to cells. Phyto-metallic nanoparticles biosynthesised from plant extracts are reported with improved functionalities for biomedical applications over those from chemical and physical methods. The synergies from the natural organic properties of the plant and the metallic properties elicit minimal cytotoxicity paving way for their different biomedical applications. This chapter is intended to provide an overview of recent advances and new perspectives in phyto-metallic nanoparticles, their biosynthesis and mechanism, therapeutics, and cytotoxicity to biomedical industries, research centres, and academia.

**Keywords:** biosynthesis, cytotoxicity, phytochemicals, nanoparticles, metal precursors, therapeutics
