•A new electrochemical sensing platform for synergetic accumulation and simultaneous determination of naphthol isomers•Simple design of electrochemical sensors for hydroxylated polycyclic aromatic hydrocarbons•Electrochemically reduced graphene oxide film accelerates the electron transfer on the electrode surfaceA novel method was developed for the synergetic accumulation and simultaneous determination of naphthol isomers (α-N and β-N) at electrochemically reduced graphene oxide modified glassy carbon electrode (E-rGO/GCE). One-step electrochemical reduction was employed for the fabrication of E-rGO/GCE, then the modified material was characterized by scanning electron microscope, Raman spectroscopy and Fourier transform infrared spectroscopy. Electrochemical behavior of naphthol isomers at E-rGO/GCE shows that the sensitivity of the isomers could be increased due to the synergistic effect of π–π conjugating and electrochemical accumulation. The oxidation peaks of α- and β-naphthol could be completely separated and the isomers were simultaneously detected with the linear ranges of 5–400 nM and 0.5–20 μM for α-N, 5–350 nM and 0.5–20 μM for β-N. The detection limits of α-N and β-N were 1.01 nM and 0.43 nM (S/N = 3), and the corresponding sensitivity were 0.0097 μA/μM and 0.0113 μA/μM, respectively. More importantly, the naphthol isomers electrochemical sensor on E-rGO film with synergistic effect can be expected to result in significant improvements in the sensor performance and the developed method has been successfully applied to human urine sample with a satisfactory result.A novel method was developed for the synergetic accumulation and simultaneous determination of naphthol isomers (α-N and β-N) at electrochemically reduced graphene oxide modified glassy carbon electrode (E-rGO/GCE).

Covalently conjugating folate on Au surface was achieved via click chemistry, copper (I)-catalyzed azide-alkyne cycloaddition reaction. Human leukemia K562 cells were used as a model system to investigate capturing cancer cells by folate-targeted electrode. Scanning optical microscopy and electrochemical method were used to monitor the capture of K562 cells on folate-clicked electrode.Highlights► Clicking folate on Au electrode. ► The folate-targeted Au surface capture cancer cells. ► As-captured cells were monitored with impedance measurements and scanning optical microscopy.

Size-controllable Ag nanoparticle ultrathin films, which were fabricated by vacuum deposition method from high purity Ag wire onto cleaned indium tin oxide conducting glass, have different color fabricated by variation of preparation conditions. The UV/Vis spectra showed that optical absorption peak of these Ag nanoparticle films can be tuned in a range from 457 nm to >650 nm. Scanning electron microscopy images showed that with increasing film thickness Ag particle size was larger. Ag/WO3 composite films were prepared by cathodic electrodeposition of WO3 onto the surface of Ag nanoparticle films. Spectroelectrochemistry and electrochromic properties of the resulting composite films were characterized. It was found that the electrochemical and electrochromatic properties of the composite films were adjustable with change the size of Ag nanoparticles in the composite films. Compared with a single component system of WO3, a substantial enhancement in the electroactive and electrochromic performance for the Ag embedded WO3 composite system was clearly observed.