One-step process for fabricating paper-based solid-state electrochemiluminescence sensor based on functionalized graphene

• One-step process was developed for fabricating solid-state ECL sensors on PCs.
• Both Ru(bpy)32 + sensor and coreactant sensor can be achieved efficiently.
• These sensors were low-cost, reagent-saving, easy-operating and with convenience.
• Functionalized graphene materials assisted the fabrication of the sensors.
• The ECL sensors can be used for sensitive direct or indirect analyte assays.

Taking advantage of simple manipulation of the screen printed electrodes, with the assistance of different functionalized graphene materials, a simple and time-saving one-step process was developed for fabricating solid-state electrochemiluminescence (ECL) sensors on paper-based chips (PCs). The solid-state Ru(bpy)32 + or co-reactant ECL sensors could be facilely obtained by screen-printing the mixture of Ru(bpy)32 +/poly(sodium 4-styrenesulfonate) functionalized graphene nanosheets (PSSG)/carbon paste or branch poly(ethylenimine) (BPEI)-functionalized graphene nanosheets (BPEIG)/carbon paste through one-step process on the PCs, respectively. The ECL behavior of Ru(bpy)32 + ECL sensor was investigated using tripropylamine (TPA) and detection limit (S/N = 3) of 5.0 nM was obtained. It also exhibited excellent reproducibility and linear relationship with the concentration of TPA (R = 0.991). In addition, the ECL behaviors of the coreactant sensor were measured for tetracycline hydrochloride (TCH) by inhibition method. A linear relationship between the ECL intensity and logarithm of the concentration of TCH was gained in a range of 1 × 10− 8 to 1 × 10− 6 M and the detection limit was as low as 2.22 nM. Therefore the one-step process for fabricating paper-based ECL sensor was confirmed with the advantages of simplicity, high efficiency and potential applicability.