title: Exogenous control over intracellular acidification: Enhancement via proton caged compounds coupled to gold nanoparticles.
abstract: The pH regulation has a fundamental role in several intracellular processes and its variation via exogenous compounds is a potential tool for intervening in the intracellular processes. Proton caged compounds (PPCs) release protons upon UV irradiation and may efficiently provoke intracellular on-command acidification. Here, we explore the intracellular pH variation, when purposely synthesized PCCs are coupled to gold nanoparticles (AuNPs) and dosed to HEK-293 cells. We detected the acidification process caused by the UV irradiation by monitoring the intensity of the asymmetric stretching mode of the CO(2) molecule at 2343 cm(-1). The comparison between free and AuNPs functionalized proton caged compound demonstrates a highly enhanced CO(2) yield, hence pH variation, in the latter case. Finally, PCC functionalized AuNPs were marked with a purposely synthesized fluorescent marker and dosed to HEK-293 cells. The corresponding fluorescence optical images show green grains throughout the whole cytoplasm.
authors.affiliation: Dept. of Chemical Sciences and Technologies, University of Rome Tor Vergata, Via della Ricerca Scientifica, 1-00133 Rome, Italy; Consorzio Interuniversitario Biostrutture e Biosistemi, Viale Medaglie d'Oro 305, 00136 Rome, Italy.
authors.forename: Marilena
authors.initials: M
authors.lastname: Carbone
authors.affiliation: Dept. of Chemical Sciences and Technologies, University of Rome Tor Vergata, Via della Ricerca Scientifica, 1-00133 Rome, Italy; Dept. of Chemistry, University of Rome La Sapienza, P.le A. Moro, 00185 Rome, Italy.
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Sabbatella
authors.affiliation: Dept. of Chemical Sciences and Technologies, University of Rome Tor Vergata, Via della Ricerca Scientifica, 1-00133 Rome, Italy.
authors.forename: Simonetta
authors.initials: S
authors.lastname: Antonaroli
authors.affiliation: Laboratoire de Chimie Physique, UMR 8000-CNRS, Bât. 349, Université Paris-Sud, 91405 Orsay, France.
authors.forename: Hynd
authors.initials: H
authors.lastname: Remita
authors.affiliation: Dept. of Biology and Biotechnology "Charles Darwin", University of Rome La Sapienza, P.le A. Moro, 00185 Rome, Italy.
authors.forename: Viviana
authors.initials: V
authors.lastname: Orlando
authors.affiliation: Dept. of Biology and Biotechnology "Charles Darwin", University of Rome La Sapienza, P.le A. Moro, 00185 Rome, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Biagioni
authors.affiliation: Dept. of Physics, University of Rome La Sapienza, P.le A. Moro, 00185 Rome, Italy; Center for Life Nano Science, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161 Rome, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Nucara
mesh_terms: D005453:Fluorescence; D006046:Gold / Q000737:chemistry*; D057809:HEK293 Cells; D006801:Humans; D006863:Hydrogen-Ion Concentration; D053768:Metal Nanoparticles / Q000737:chemistry*; D011522:Protons
chemical_list: D011522:Protons; D006046:Gold
keywords: Gold nanoparticles; Intracellular acidification; Proton caged compounds; pH monitoring