Carrillo Carrión, CarolinaMartínez González, RaquelPolo Tobajas, EsterTomás Gamasa, MaríaDestito, PaoloCeballos Guzmán, ManuelPelaz García, BeatrizLópez García, FernandoMascareñas Cid, José LuisPino González de la Higuera, Pablo Alfonso del2021-10-272021-10-272021ACS Nano 2021, 15, 16924−169331936-0851http://hdl.handle.net/10347/27035We describe a microporous plasmonic nanoreactor to carry out designed near-infrared (NIR)-driven photothermal cyclizations inside living cells. As a proof of concept, we chose an intramolecular cyclization that is based on the nucleophilic attack of a pyridine onto an electrophilic carbon, a process that requires high activation energies and is typically achieved in bulk solution by heating at ∼90 °C. The core–shell nanoreactor (NR) has been designed to include a gold nanostar core, which is embedded within a metal–organic framework (MOF) based on a polymer-stabilized zeolitic imidazole framework-8 (ZIF-8). Once accumulated inside living cells, the MOF-based cloak of NRs allows an efficient diffusion of reactants into the plasmonic chamber, where they undergo the transformation upon near-IR illumination. The photothermal-driven reaction enables the intracellular generation of cyclic fluorescent products that can be tracked using fluorescence microscopy. The strategy may find different type of applications, such as for the spatio-temporal activation of prodrugseng© 2021 The Authors. Published by American Chemical Society. This document is licensed under a Creative Commons Attribution 4.0 International license (https://creativecommons.org/licenses/by/4.0/legalcode)Atribución 4.0 Internacionalhttp://creativecommons.org/licenses/by/4.0/Bio-orthogonal chemistryNanocompositesThermoplasmonicsIntracellular thermocyclizationThermolabile protecting groupsjournal article10.1021/acsnano.1c079831936-086Xopen access