Glahn Martínez, Ana BettinaJurado-Sánchez, BeatrizBenito Peña, María ElenaEscarpa, AlbertoMoreno Bondi, María Cruz2024-01-162024-01-162024Glahn-Martínez, Bettina, et al. «Magnetic Janus Micromotors for Fluorescence Biosensing of Tacrolimus in Oral Fluids». Biosensors and Bioelectronics, vol. 244, enero de 2024, p. 115796. https://doi.org/10.1016/j.bios.2023.115796.0956-566310.1016/j.bios.2023.115796https://hdl.handle.net/20.500.14352/93325Tacrolimus (FK506) is a macrolide lactone immunosuppressive drug that is commonly used in transplanted patients to avoid organ rejection. FK506 exhibits high inter- and intra-patient pharmacokinetic variability, making monitoring necessary for organ graft survival. This work describes the development of a novel bioassay for monitoring FK506. The bioassay is based on using polycaprolactone-based (PCL) magnetic Janus micromotors and a recombinant chimera receptor that incorporates the immunophilin tacrolimus binding protein 1A (FKBP1A) tagged with Emerald Green Fluorescent Protein (EmGFP). The approach relies on a fluorescence competitive bioassay between the drug and the micromotors decorated with a carboxylated FK506 toward the specific site of the fluorescent immunophilin. The proposed homogeneous assay could be performed in a single step without washing steps to separate the unbound receptor. The proposed approach fits the therapeutic requirements, showing a limit of detection of 0.8 ng/mL and a wide dynamic range of up to 90 ng/mL. Assay selectivity was evaluated by measuring the competitive inhibition curves with other immunosuppressive drugs usually co-administered with FK506. The magnetic propulsion mechanism allows for efficient operation in raw samples without damaging the biological binding receptor (FKBP1A-EmGFP). The enhanced target recognition and micromixing strategies hold considerable potential for FK506 monitoring in practical clinical use.engAttribution-NonCommercial-NoDerivatives 4.0 InternationalMagnetic Janus micromotors for fluorescence biosensing of tacrolimus in oral fluidsjournal articlehttps://doi.org/10.1016/j.bios.2023.115796https://www.sciencedirect.com/science/article/pii/S0956566323007388open access543Bioluminescent assayRecombinant proteinTacrolimusTacrolimus binding protein 1AEmerald green fluorescent proteinMicromotorsJanusQuímica analítica (Química)23 Química32 Ciencias Médicas24 Ciencias de la Vida33 Ciencias Tecnológicas