title: A new specific fullerene-based fluorescent probe for trypsin.
abstract: A novel fluorescent probe (C(60)-FL) was designed and synthesized for the direct determination of trypsin, based on photo-induced electron transfer (PET). The probe consists of two functional moieties: fluorescein which performs as a fluorophore and an electron donor, and fullerene (C(60)) which acts as an electron acceptor and trypsin substrate analogue. In the presence of trypsin, the probe exhibited fluorescence increase due to the inhibition of electron transfer by the combination of C(60)-FL with trypsin. The response of the probe to trypsin was direct and rapid. Experimental results showed that the increase in fluorescence intensity is proportional to the concentration of trypsin within the range of 4.40×10(-7) to 7.04×10(-5) g mL(-1) under the optimized experimental conditions. The detection limit of the proposed method was 40 ng mL(-1). The method had high selectivity for trypsin over other enzymes and proteins, such as lipase, α-amylase, bovine serum albumin, zinc metallothionein, glutathione reductase, thioredoxin and α-chymotrypsin etc. The remarkable properties of C(60)-FL help to extend the development of fluorescent probes for investigating enzymes in a biological context.
authors.affiliation: College of Chemistry, Chemical Engineering and Materials Science, Engineering Research Center of Pesticide and Medicine Intermediate Clean Production, Ministry of Education, Key Laboratory of Molecular and Nano Probes, Ministry of Education, Shandong Normal University, Jinan, 250014, PR China.
authors.forename: Kehua
authors.initials: K
authors.lastname: Xu
authors.forename: Fen
authors.initials: F
authors.lastname: Liu
authors.forename: Jing
authors.initials: J
authors.lastname: Ma
authors.forename: Bo
authors.initials: B
authors.lastname: Tang
mesh_terms: D004579:Electron Transport; D005456:Fluorescent Dyes / Q000737:chemistry*; D037741:Fullerenes / Q000737:chemistry*; D057230:Limit of Detection; D013050:Spectrometry, Fluorescence / Q000295:instrumentation / Q000379:methods*; D014357:Trypsin / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism
chemical_list: D005456:Fluorescent Dyes; D037741:Fullerenes; D014357:Trypsin