An enzymatic calculation system based on electrochemiluminescence and fluorescence of luminol and cyclic voltammetry of ferrocene methanol

In this work, a biomolecular calculation system was developed based on electrochemiluminescence (ECL) and fluorescence emission (FL) of luminol and cyclic voltammetry (CV) of ferrocene methanol (FMA). When triethylamine (TEA) was added in luminol solution as a coreactant, a great ECL peak at 1.1 V was observed. While the further addition of enzymatic system, esterase/ethyl butyrate (EB), would significantly lower the ECL response. On the other hand, TEA could quench the FL signal of luminol at 430 nm, while the injection of esterase/EB in the luminol solution could enhance the FL signal. Furthermore, FMA exhibited a CV peak pair at 0.2 V and could decrease the ECL signal greatly in the luminol/TEA solution. Based on these interesting results, a 3-input and 5-output biomolecular logic gate was established with TEA, FMA and esterase/EB as inputs and the ECL, CV and FL signals as outputs. Moreover, some nonarithmetic logic devices, such as an encoder, a decoder, a 3-input keypad lock and two dual transfer gates were elaborately designed on the same platform. This work presented a new example of how the complexity of biocomputing system could be enhanced either by increasing the number of outputs of traditional logic gates or by fabricating some nonarithmetic logic devices based on the same simple electrochemical system.