The Composites of Asymmetric Co Phthalocyanines-Graphitic Carbon Nitride Quantum Dots-Aptamer as Specific Electrochemical Sensors for the Detection of Prostate Specific Antigen: Effects of Ring Substituents

Asymmetrical phthalocaynine molecules have been employed, in combination with graphitic carbon nitride quantum dots covalently linked to an amine-functionalized aptamer for the electrochemical detection of prostate cancer biomarker. The combination of these complexes with the quantum dots-aptamer conjugate resulted in overall improved electrocatalytic ability as well as enhanced signal response. Moreover, results proved one of the complexes being superior over the other functionality wise, indicating the significance of substituent type of the phthalocyanines. The best performing aptasensor showed detection limits as low as 0.23 ng/mL in buffer solutions as well as 0.27 ng/mL in serum samples. Moreover, the sensor showed good stability, reproducibility and repeatability.