Shujie Hu,Zhiyuan Cao,Lin Zhou,Rongliang Ma,Bin Su
An efficient method has been developed for visualizing latent fingerprints by spatially selective electropolymerization of luminol on the ITO electrode. The fingerprint deposited on the electrode surface functions as a mask so that polyluminol is formed on the bare electrode surface. Therefore, electrochemiluminescence is only generated between the ridges of fingerprint, eventually yielding a negative ECL image. This method is easy to operate and safe to examiners. In addition, the second- and third-level details of fingerprints can be well resolved, indicating the potential application for personal identification and forensic investigation.
Caixia Wang,Liming Chen,Peijin Wang,Mengsi Li,Defang Liu
In this work, an ultrasensitive electrochemiluminescence (ECL) biosensor was constructed using poly- L -lysine (PLL) as a novel co-reactant of luminol and poly(luminol/aniline) nanorods loaded reduced graphene oxide ( [email protected] ) as nanoprobe, which enable highly sensitivity detection of glutathione (GSH). To the best of our knowledge, it is the first time that PLL was used for the co-reactant of luminol. Notably, about a 5-fold enhancement was obtained compared with the individual [email protected] using GCE . Due to the remarkable quenching effect between the excited state of PLL and the reduced form of GSH in the ECL system of luminol/PLL, the ECL sensing platform exhibited wide linear ranges of 1.0 × 10 −9 –1.0 × 10 −4 M and 1.0 × 10 −4 –1.0 × 10 −2 M and a low detection limit of 7.7 × 10 −10 M. Simultaneously, the biosensor was also successfully applied to detect GSH in human serum sample with high recoveries. Hence, this work would open a new platform for the wide application of PLL in immunoassay and various sensors.