biostudies-literatureUnknown4(5)Al-Hawat MLAmmonia is a key biomarker in inborn and acquired liver disease. As clinical point-of-care blood ammonia assays are lacking, we developed a polymersome formulation for point-of-care blood ammonia sensing combined with a portable fluorometer. A pH-sensitive near-infrared (NIR) fluorescent dye was identified, which showed a strong fluorescence increase at acidic pH values. Building on reports on ammonia-selective PS-<i>b</i>-PEG polymersomes, these polymersomes were loaded with the NIR dye. These NIR fluorescent polymersomes sensed ammonia in a clinically relevant range in ammonia-spiked fresh whole blood with high linearity (<i>R</i> ² = 0.9948) after 5 min using a conventional tabletop plate reader. Subsequently, the assay was tested with a portable fluorometer. An ammonia-dependent fluorescence increase was detected in ammonia-spiked fresh mouse blood after 5 min using the portable fluorometer. The NIR dye-loaded PS-<i>b</i>-PEG polymersomes rapidly sensed ammonia with high linearity in whole blood. This assay was successfully combined with a portable fluorometer and only required 3 μL of blood. These findings motivate a further development and clinical translation of this point-of-care blood ammonia assay.ACS bio & med chem Au226-232https://www.ebi.ac.uk/biostudies/studies/S-EPMC11487535biostudies-literatureDevelopment of a Polymersome Blood Ammonia Assay Coupled with a Portable Near-Infrared Fluorometer.PMC11487535Al-Hawat MLDjebbar SCaron JMatoori SfalseDevelopment of a Polymersome Blood Ammonia Assay Coupled with a Portable Near-Infrared Fluorometer.Ammonia is a key biomarker in inborn and acquired liver disease. As clinical point-of-care blood ammonia assays are lacking, we developed a polymersome formulation for point-of-care blood ammonia sensing combined with a portable fluorometer. A pH-sensitive near-infrared (NIR) fluorescent dye was identified, which showed a strong fluorescence increase at acidic pH values. Building on reports on ammonia-selective PS-<i>b</i>-PEG polymersomes, these polymersomes were loaded with the NIR dye. These NIR fluorescent polymersomes sensed ammonia in a clinically relevant range in ammonia-spiked fresh whole blood with high linearity (<i>R</i> ² = 0.9948) after 5 min using a conventional tabletop plate reader. Subsequently, the assay was tested with a portable fluorometer. An ammonia-dependent fluorescence increase was detected in ammonia-spiked fresh mouse blood after 5 min using the portable fluorometer. The NIR dye-loaded PS-<i>b</i>-PEG polymersomes rapidly sensed ammonia with high linearity in whole blood. This assay was successfully combined with a portable fluorometer and only required 3 μL of blood. These findings motivate a further development and clinical translation of this point-of-care blood ammonia assay.2024-01-01T00:00:00Z2024 Oct2025-04-04T20:55:56.845Z2025-04-04T20:55:56.845ZS-EPMC114875353943126610.1021/acsbiomedchemau.4c00013