Calotropis gigantea assisted green synthesis of nanomaterials and their applications: a review

Abstract

Abstract Background Nanotechnology has been receiving wonderful impetus in the current emerging technological era by opening a pool of scientific ideas to compete with the daily challenges of developing technology. So far, numerous properties and countless applications of nanomaterials have been explored which have been even proved to be based on characteristic shape, size, surface area and surface chemistry. Main content By the time, several attempts have been made for green synthesis of nanomaterials, using plant extracts. Calotropis gigantiea (L.) R. Br is the plant belonging to Apocynaceae, have been screened and proved to possess various pharmacological activities, due to different polar phytochemicals like flavonoids, lignans and terpenoids. This review focus on phytochemicals so far reported from different parts of the plant; pharmacological activities exhibited; green synthesis of nanomaterials, particularly metallic nanoparticles green synthesised by facilitating reaction of metallic ion donor molecule/salt and aqueous extract of leaves or flowers of C. gigantiea and their biological or non-biological applications. The use of C. gigantea in the fabrication of nanomaterials is an eco-friendly and safe approach. Secondary metabolites present act as a stabilizing agent for nanomaterials. Cadmium sulphide, titanium dioxide, nickel and nickel oxide nanoparticles synthesised using C. gigantea exerted better anti-microbial action, compared to extracts. Nanoencapsulated magnesium oxide nanoparticles avoided biochemical degradation of MgO; increase its bioavailability and proved beneficial in type II diabetes mellitus. Cupric oxide nanoparticles got applied in dye-sensitised solar cell. Silver nanoparticles showed better cytotoxicity in HeLa cells. Biomaterial-supported zero-valent iron and stannic oxide nanoparticles proved to have utilities in water purification. Green synthesised Eu3+ doped Y2SiO5 nanophosphors had significant chromaticity coordinates and average correlated colour temperature, hence find application in displays. Conclusion Variety of nanomaterials including nanoparticles and nanophophors could successfully be biosynthesised using Calotropis gigantean extract or its latex. These green synthesised nanomaterials have several applications in the healthcare system and technology. Graphical Abstract