TiOsub2/sub nanotubes loaded with CdS nanocrystals as enhanced emitters of electrochemiluminescence: application to an assay for prostate-specific antigen

摘要

titleAbstract/titlepAn enhanced cathodic electrochemiluminescence (ECL) assay for prostate-specific antigen (PSA) is developed based on the in situ activation of a semiconductor nanomaterial. An excellent ECL emitter (CdS/TiOsub2/sub nanotubes) was fabricated by the combination of TiOsub2/sub nanotubes (NTs) and thioglycolic acid-capped CdS nanocrystals (NCs). After the activation of the hydrogen peroxide-citric acid solution, the ECL signal was enhanced 265 times compared with that of the original TiOsub2/sub NT with Hsub2/subOsub2/sub as co-reactant. For the ECL assay, activated CdS/TiOsub2/sub NTs were assembled with complementary DNA, PSA aptamer and probe DNA-functionalized SiOsub2/sub@Pt nanoparticles (NPs) via DNA hybridization to form the detection platform. The SiOsub2/sub@Pt NPs acted as ECL quencher of CdS/TiOsub2/sub NTs. In the presence of PSA, ECL increased after the release of pDNA-SiOsub2/sub@Pt NPs because of the binding of PSA to the aptamer. An “off-on” ECL phenomenon appeared. The enhanced ECL signals were used for sensitive determination of PSA. The dynamic range was 0.001 to 50?ng?mLsup?1/sup with a detection limit of 0.4?pg?mLsup?1/sup (S/italicN/italic?=?3). This new approach conceivably paves the way for fabricating various other enhanced ECL emitter systems, with good application prospects in clinical practice./ppfiglabelGraphical abstract/labelcaptionpThe activated CdS/TiOsub2/sub nanotubes and SiOsub2/sub@Pt nanoparticles were synthesized and used to develop an energy-transfer electrochemiluminescence analysis method with high sensitivity and anti-interference performance./p/captiongraphic/graphic/fig/p