REVIEW ARTICLE Nanomaterial-based electrochemical sensors and optical probes for detection and imaging of peroxynitrite: a review Alina Vasilescu 1 & Mihaela Gheorghiu 1 & Serban Peteu 2 Received: 11 November 2016 /Accepted: 17 January 2017 /Published online: 1 February 2017 # Springer-Verlag Wien 2017 Abstract Peroxynitrite (PON for short) is a powerful nitrating, nitrosating and oxidative agent for cellular constitu- ents. In vivo, PON is formed through the diffusion-controlled reaction between superoxide radical (O 2 •- ) and nitric oxide (•NO). This critical review (with 67 refs.) covers the state of the art in nanomaterial-based (a) detection and imaging of PON inside cells and (b) monitoring of cellular events such as cellular oxidative burst by using optical or electrochemical methods. It starts with the formation, fate and pathophysiology of PON in vivo. The next part summarizes nanomaterial based electro- chemical microsensors featuring nanofilms and nanostructured electrodes, nanospheres, 3D nanostructures and graphene- supported catalysts. A following chapter covers techniques based on optical nanoprobes, starting with nanomaterials used in optical detection of PON (including quantum dots, carbon dots, fluores- cent organic polymer dots, rare earth nanocrystals including upconversion nanoparticles, iron oxide nanoparticles, gold nano- particles, and fluorophore-modified nanoporous silicon). This is followed by subsections on strategies for optical detection of PON (including color changes, fluorescence quenching, activa- tion and recovery), and on schemes for optimized spatial and temporal resolution, for improving sensitivity, selectivity, and (photo)stability. We then address critical issues related to biocom- patibility, pharmacokinetics, give a number of representative practical applications and discuss challenges related to PON de- tection. The review concludes with a discussion of latest devel- opments and future perspectives. Keywords Selectivity . Response time . Dynamic assay . Graphene . Short lived species . Ratiometric fluorescence . Theranostic . Biocompatibility Abbreviations AG Aminoguanidine AuNCs Gold nanoclusters AuNPs Gold nanoparticles BzSe-Cy Benzylselenide-tricarbocyanine CA Citric acid CV Cyclic voltammetry CDs Carbon dots CF-SPN Semiconductor polymer nanoparticles for combined CRET and FRET CLIO Cross-linked iron oxide CRET Chemiluminescence resonance energy transfer DCF 2′,7′-dichlorofluorescein DL Detection limit EPR Enhanced permeability and retention FRET Fluorescence resonance energy transfer. GCE Glassy carbon electrode GSH– TGA –CdTe@ ZnS Core-shell quantum dots with CdTe core capped with TGA and shell of ZnS capped with GSH (GSH– TGA –CdTe@ ZnS) HA Hyaluronic acid iNOS Inducible nitric oxide synthase IRhB Isopropylrhodamine B Alina Vasilescu and Mihaela Gheorghiu have contributed equally to this paper. * Serban Peteu peteu@msu.edu 1 International Centre of Biodynamics, 1B Intrarea Portocalelor, 060101 Bucharest, Romania 2 Department of Chemistry, Michigan State University, 578 S Shaw Lane, East Lansing, MI 48824, USA Microchim Acta (2017) 184:649–675 DOI 10.1007/s00604-017-2093-7