{"doi":"10.1039/d1tb00643f","title":"A ratiometric near-infrared fluorescent probe based on a novel reactive cyanine platform for mitochondrial pH detection","abstract":"A near-infrared reactive cyanine platform (probe A) was prepared by condensation of 9-chloro-1,2,3,4-tetrahydro-10-methyl-acridinium iodide with Fisher's aldehyde. A near-infrared fluorescent probe (probe B) was prepared by modifying a reactive chlorine atom of probe A with tert-butyl(2-aminoethyl)carbamate through a substitution reaction. The deprotection of the Boc group of probe B was achieved under an acidic condition, affording an amine-functionalized cyanine dye (probe C). A near-infrared ratiometric fluorescent probe (probe D) for mitochondrial pH detection was synthesized by conjugating a FRET coumarin donor to a FRET cyanine acceptor (probe C) through an amide bond connection. Probe A shows low fluorescence of 2% due to an electron-withdrawing chlorine atom, while probes B-D display high fluorescence quantum yields of 60%, 32%, and 35% in aqueous solutions containing 10% ethanol, respectively. Probes B-D show strong fluorescence with push-pull molecular structures in neutral and basic pH conditions. However, protonation of the probe's second amine at the 9-position under acidic condition disrupts the push-pull feature of the probes, resulting in fluorescence quenching of the new cyanine fluorophores. The probes can selectively stain mitochondria, while probe D was employed to detect pH changes in HeLa cells and Drosophila melanogaster first-instar larvae.","journal":"Journal of Materials Chemistry B","year":2021,"id":158381,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":46,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.955,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2021-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":325034,"name":"Shuai Xia","orcid":"0000-0002-3323-0342","position":1,"is_corresponding":false},{"id":667463,"name":"Jerry Medford","orcid":null,"position":2,"is_corresponding":false},{"id":667464,"name":"Emma Durocher","orcid":null,"position":3,"is_corresponding":false},{"id":451577,"name":"Tessa E. Steenwinkel","orcid":"0000-0002-3949-930X","position":4,"is_corresponding":false},{"id":667465,"name":"Lexi Rule","orcid":null,"position":5,"is_corresponding":false},{"id":325033,"name":"Yibin Zhang","orcid":"0000-0002-6626-0863","position":6,"is_corresponding":false},{"id":325036,"name":"Rudy L. Luck","orcid":"0000-0001-5436-1942","position":7,"is_corresponding":false},{"id":451580,"name":"Thomas Werner","orcid":"0000-0002-8865-365X","position":8,"is_corresponding":false},{"id":325037,"name":"Haiying Liu","orcid":"0000-0001-8351-2017","position":9,"is_corresponding":false},{"id":327249,"name":"Shulin Wan","orcid":null,"position":0,"is_corresponding":true}],"reference_count":43,"raw_metadata":null,"created_at":"2026-07-18T23:44:26.210708Z","pmid":"34132313","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}