Insights of nanomaterials integrated analytical approaches for detection of plant hormones in agricultural and environmental samples

Hormones are an important class of biomolecules as they regulate the physiological responses in the living organisms. Recently, nanomaterials-based biosensors have been widely researched due to their outstanding merits like stabilty, selectivity, biocompatibility, facile synthetic approach, and cost-effectiveness. In this review, we cover in detail the recent advancements of nanomaterials (carbon dots, carbon nanotubes, metal nanoparticles, metal oxides, metal-organic frameworks, metal nanoclusters and quantum dots) in electrochemcial, colorimetric and fluorescence sensing of plant hormones. This review also provides a brief outline on the classificaiton of phytohormones and the sample preparation appraoches for the extraction of phytohormones prior to their identification by various analytical techniques. This review will focus on the selected research papers on nanomaterials as electrochemical, colorimetric and fluorescent sensors for the plant hormones detection from the last twelve years (i.e., 2011 −2023). Nanomaterials integrated analytical techniques (electrochemcial, colorimetric and fluorescence) offer to detect plat hormones with lower detection limits (fM to µM and ng/mL to pg/mL). Importantly, nanomaterials integrated analytical strategies have been successfully detected plant hormones with minimal volumes and sample preparations. The various advantages and limitations of techniques have been also overviewed. The challenges and future perspectives of nanomaterials-based electro- and optical sensors for the analysis of plant hormones are discussed in detail.