Fluorescent Determination of Uric Acid Based on Porphyrin and ZnCo₂O₄ Nanocomposite

Advances in porphyrin chemistry have provided exciting technologies in the field of optical biosensing. Herein, we have synthesized 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin (TCPP) and porous Zn_0.1Co₂O₄ nanorods using a simple one-pot hydrothermal method. The obtained TCPP- Zn_0.1Co₂O₄ composite was then used for the development of a novel optical sensor for the determination of uric acid (UA), which is an important biomarker in human urine, serum or saliva for the clinical diagnosis of hyperuricemia and hypouricemia, etc. TCPP-Zn_0.1Co₂O₄ composite was characterized using SEM, TEM, EDAX, PXRD, FT-IR, UV-Visible, and NMR spectroscopic techniques. The fluorescence emission spectral analysis of TCPP-Zn_0.1Co₂O₄ was then investigated for potential applications in the detection of uric acid via the fluorescence quenching mechanism. The designed sensor showed a linear response towards the uric acid in the concentration range of 0.99 to 5.2 nM. The optical sensor exhibits a sensitive response to uric acid with a detection limit of 0.015 nM. The sensor was employed to quantify UA in spiked human urine samples and artificial urine with satisfactory results.