Diasi, ManabManabDiasiSingh, RinkiRinkiSinghMahapatra, Amarjyoti DasAmarjyoti DasMahapatraRenuka, L.L.RenukaPatel, HitarthHitarthPatelGanatra, HasitHasitGanatraDatta, BhaskarBhaskarDatta2025-08-312025-08-312024-02-2710.1039/d3ra07606g2-s2.0-85186127131https://d8.irins.org/handle/IITG2025/29030In this work, we have studied the ability of urease immobilized on glutaraldehyde crosslinked chitosan coated magnetic iron oxide nanoparticles (Urease/GA/CS/MIONPs), for the hitherto unreported comparative hydrolysis of urea in synthetic (SUr) and real human urine (HUr). The prepared Urease/GA/CS/MIONPs were characterized by a combination of Fourier transform infrared spectroscopy (FTIR), field emission-scanning-electron-microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX) and dynamic light scattering (DLS). The nanoconstructs display the highest ammonium ion liberation post-urea hydrolysis in 1/20 or 1/24-fold dilutions of SUr and HUr, respectively. The optimum activity of immobilized urease is observed at pH 7, and the nanoconstructs facilitate efficient urea-hydrolysis till at least 45 °C. Kinetic analysis of the immobilized urease shows k<inf>m</inf> and v<inf>max</inf> of 14.81 mM, 12.36 mM, and 18.55 μM min⁻¹ and 10.10 μM min⁻¹, towards SUr and HUr, respectively. The magnetization of the immobilized urease is suitable for reuse across multiple cycles of urea hydrolysis in SUr and HUr. The robust performance of Urease/GA/CS/MIONPs in SUr and HUr is promising for generating ammonium as a useable source of nitrogen from human urine, and underscores the suitability of SUr as a urine mimic for such interventions.trueArticlehttps://pubs.rsc.org/en/content/articlepdf/2024/ra/d3ra07606g204620696972-698427 February 20243arJournal5WOS:001173779300001