An alternative label-free DNA sensor based on the alternating-current electroluminescent device for simultaneous detection of human immunodeficiency virus and hepatitis C co-infection.

Coinfection of HIV/HCV is a significant public health issue globally, as it increases the risk of liver cancer in co-infected individuals. The point-of-care testing (POCT) device for HIV/HCV DNA detection is promptly needed for diagnosis and monitoring of the disease progression. Here, the alternating-current electroluminescence (ACEL) technique is proposed as a sensitive POCT sensing platform for HIV/HCV cDNA detection. A conductance-based light emission modulated by the hybridization between a pyrrolidinyl PNA probe and the DNA target enabled the DNA detection in a label-free format. Enhanced electroluminescence was observed in the presence of the target DNA due to the increased proton conductivity. Under the optimal conditions, the linearity range from 1 nM to 1 μM was achieved for HIV and HCV cDNA with LODs of 1.86 pM (HIV cDNA) and 1.96 pM (HCV cDNA). The spiked HIV/HCV cDNA in healthy human serum was successfully detected, demonstrating the feasibility of the developed device for the detection of cDNA in real biological samples. Additionally, simultaneous HIV/HCV cDNA detection on a single ACEL device employing a 2x2-array detection zone design. The cross-reactivity with other viral DNA was shown to be minimal due to the high specificity of the PNA probes used. Finally, the negative and positive samples from the patient's serum were tested and the results were in 100% agreement with the commercial kit based-on real-time PCR method, thus illustrating the high sensitivity and specificity of the developed sensor.