title: CdSe quantum dot-functionalized TiO2 nanohybrids as a visible light induced photoelectrochemical platform for the detection of proprotein convertase subtilisin/kexin type 6.
abstract: Proprotein convertase subtilisin/kexin type 6 (PCSK6) plays a major role in promoting the progression of rheumatoid arthritis to a higher aggressive status. A novel highly sensitive photoelectrochemical platform was developed for the detection of PCSK6 by using CdSe quantum dots (QDs)-functionalized TiO2 nanoparticles (NPs) nanohybrids (TiO2@CdSe) as the photo-to-electron conversion medium. TiO2@CdSe showed excellent visible-light absorbency, and much higher photoelectrochemical activity than both CdSe QDs and TiO2 NPs. The 5' and 3' primers of PCSK6 ssDNA acted as capture probes to realize the detection of PCSK6 ssDNA by the specific recognition. The capture probes can be fixed by poly-l-lysine (PLL) through positively strong electrostatic attraction and the carboxyl group of TiO2@CdSe nanohybrids. PLL was electropolymerized on ITO electrode by cyclic voltammetry (CV). Simultaneously, the amino group of PLL can interact with the carboxyl group of TiO2@CdSe nanohybrids to enhance the stability of the photoelectrochemical signal. The fabricated aptsensor exhibited excellent performance towards PCSK6 with a wide linear range (0.5 pg/mL to 80.0 ng/mL) and a detection limit of 0.1 fg/mL. This work opens up a new detection platform for PCSK6 with good sensitivity, reproducibility and stability.
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
authors.forename: Xuehui
authors.initials: X
authors.lastname: Pang
authors.affiliation: Shandong Medicinal Biotechnology Centre, The Key Lab for Biotechnology Drugs of Ministry of Health, The Key Lab of Rare and Uncommon Disease, Jinan 250022, China.
authors.forename: Jihong
authors.initials: J
authors.lastname: Pan
authors.affiliation: Shandong Medicinal Biotechnology Centre, The Key Lab for Biotechnology Drugs of Ministry of Health, The Key Lab of Rare and Uncommon Disease, Jinan 250022, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Wang
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Ren
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
authors.forename: Picheng
authors.initials: P
authors.lastname: Gao
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China. Electronic address: sdjndxwq@163.com.
authors.forename: Qin
authors.initials: Q
authors.lastname: Wei
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Du
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation; D019187:Cadmium Compounds / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000295:instrumentation*; D004566:Electrodes; D006801:Humans; D008027:Light; D057230:Limit of Detection; D011107:Polylysine / Q000737:chemistry; D043484:Proprotein Convertases / Q000032:analysis*; D045663:Quantum Dots / Q000737:chemistry* / Q000648:ultrastructure; D015203:Reproducibility of Results; D018036:Selenium Compounds / Q000737:chemistry*; D012697:Serine Endopeptidases / Q000032:analysis*; D014025:Titanium / Q000737:chemistry*
chemical_list: D019187:Cadmium Compounds; D018036:Selenium Compounds; C009495:titanium dioxide; D011107:Polylysine; C058667:cadmium selenide; D014025:Titanium; C080654:PCSK6 protein, human; D043484:Proprotein Convertases; D012697:Serine Endopeptidases
keywords: Nanohybrids; PCSK6; Photoelectrochemical aptsensor; TiO(2)@CdSe