Examination of influence of microfluidic flow and antibody orientation on biosensor performance: A case study with...

Ovarian cancer has always posed a challenge to the healthcare industry due to a lack of early diagnosis methods, attributed to the absence of identifiable symptoms, thereby earning it the name "silent killer". Even though the traditional diagnostic methods provide some diagnostic capabilities, they still face several bottlenecks, highlighting the need to develop a robust, sensitive and accurate biosensor, specific to ovarian cancer biomarkers. In this study, an electrochemical platform with the microfluidic method of sample introduction was analyzed to detect cancer antigen 125 (CA125), a prominent biomarker in ovarian cancer patients. The platform was decorated with alkylamine-functionalized graphene sheets (A_fGSs) and antibody aligner to act as bio-conjugation and signal-enhancing agents. Thorough structural and functionalization characterizations of the nanomaterial and sensing platform were performed. The study presents a detailed comparison of the performance of both static (drop-cast) and microfluidic sensing platforms for CA125 biomarker concentrations in the 0.0001-1000 U/mL range, with a Limit of Detection (LoD) of 6.17 μU/mL for microfluidic systems and 2.67 μU/mL for static systems.