Label-free 3D-printed immunosensor based on neodymium metallic-organic framework for point-of-care monitoring of prostate cancer biomarker.

Given the challenges posed by late diagnosis of prostate cancer, rapid point-of-care testing is crucial to facilitate early intervention and enhance treatment effectiveness. In this context, 3D-printed immunosensors represent a promising alternative for the development of low-cost, miniaturized, and reliable diagnostic tools. Accordingly, a neodymium-based metal-organic framework (Nd-MOF) was integrated onto conductive 3D-printed electrodes to develop a label-free voltammetric immunosensor for the monitoring of prostate-specific antigen (PSA). Spectroscopic characterizations indicated the anchoring of the PSA antibody through the free carboxylic groups in the Nd-MOF structure. This platform exhibited redox behavior resulting from methylene blue adsorbed Nd-MOF, while its functional groups enabled PSA antibody immobilization. The different steps for the construction of 3D-printed immunosensor and the evaluation of PSA biorecognition were assessed by cyclic voltammetry. The 3D-printed immunosensor exhibited excellent analytical performance over a linear range of 0.50 to 50.0 ng mL-1, with a low limit of detection of 0.15 ng mL-1. Moreover, the platform showed remarkable repeatability (RSD <4.80%) and stability over successive measurements, confirming its reliability for accurate PSA monitoring. In addition, the 3D-printed immunosensor demonstrated sensitivity for PSA determination in spiked serum samples. The simple fabrication, and integration of methylene blue adsorbed Nd-MOF with 3D-printed electrodes highlight the potential of platform for point-of-care diagnostics, especially in resource-limited settings.