Facile Fabrication of Poly(Acrylic Acid)-Functionalised Nickel-Metal-Organic Frameworks Nanoplates for Electrochemical Immunosensor for the Detection of Prostate-Specific Antigen

The Current study proposes the first application of nanoplate poly(acrylic acid)-modified Nickel-2-Amino-1,4-benzene dicarboxylic (PAA−Ni−NH₂BDC) for quantifying PSA in serum. The MOF surface was functional with poly(acrylic acid) (PAA) to supply carboxylic groups. Anti-PSA antibodies were immobilised onto the modified electrode using EDC-NHS chemistry facilitated by the carboxylic groups supplied by PAA. Differential pulse voltammetry was used to study the sensor's performance towards prostate-specific antigen using 2.5 mM Fe (CN)₆]³⁻/[Fe(CN)₆]⁴⁻ in 0.01 M PBS as a redox probe. The immunosensor exhibited a detection limit of 1.0×10⁻¹³ μg/L with a wide linear range of 10⁻¹³ to 10⁻³ μg/L. The MOF′s high surface area and large pore sizes allowed the material to adsorb large quantities of the anti-PSA antibodies for enhanced performance. Furthermore, the results from the proposed technique were highly reproducible. The PAA-NI-MOF may be useful for early prostate cancer detection in clinical diagnosis and monitoring.