An amplification-free portable electrochemical device for HPV L1 protein detection towards point-of-care early cervical cancer risk screening

Cervical cancer ranks as the fourth most common cancer and is the third leading cause of cancer-related deaths among women worldwide. Globally, an estimated of 66,0000 women were diagnosed with cervical cancer, with 35,0000 deaths in 2022. Traditional cervical cancer screening techniques, including pap smear, visual inspection with acetic acid (VIA), and PCR-based HPV DNA assays, require advanced centralised laboratories, complex sample preprocessing, skilled personnel, high operational costs, and long turnaround time, thereby restricting their availability in point-of-care, limited-resource settings where extensive screening is essential. The reported electrochemical sensor overcomes the limitations of traditional methods by developing an amplification-free, sample pre-processing-free, nanoparticle-free, smartphone-integrated electrochemical sensing platform, which can detect HPV L1 protein from unprocessed cervical swab samples. The sensor exhibits high sensitivity with a detection limit of 0.29 pM in a wide detection range of 1 pM - 6 nM. Further, the aptasensor shows high reproducibility of RSD 3.85 %, selectivity, and stability up to 30 days at room temperature. All the electrochemical signal responses in the presence of cervical swab samples exhibit high correlation with conventional COBAS testing. Commercially, the fabrication cost for the disposable sensor chip is very low (0.07 USD), which is very important for population-based screening and point-of-care testing. The compatibility for large-scale fabrication and integration with portable readout systems like smartphones also broadens its market appeal in point-of-care diagnostic sectors.