5 research outputs found
Sequential flow injection analysis with potentiometric detection for the determination of ammonium and urea in human saliva
info:eu-repo/semantics/publishedVersio
Microfluidic paper-based analytical device (碌PAD) for salivar ammonia/ammonium
info:eu-repo/semantics/publishedVersio
Study of the effect of chronic kidney disease on urea and ammonia levels in saliva using a sequential injection system with potentiometric detection
info:eu-repo/semantics/publishedVersio
Micro-PAD card for measuring total ammonia nitrogen in saliva
This work presents a portable microfluidic paper-based analytical device (micro-PAD) card for the quantification of total ammonia nitrogen in human saliva. The amount of total ammonia nitrogen in saliva can be an indicator of the status of the oral microbiome with potential correlation to kidney health problems. The developed micro-PAD card comprises twenty units consisting of three stacked layers of circular discs: the sample layer, paper discs impregnated with sodium hydroxide solution, the PTFE membrane layer, and the detection layer, paper discs impregnated with bromothymol blue. The twenty units were aligned on transparent laminating pouches laminated to form the micro-PAD card (7.5 cm 脳 10.5 cm). Saliva samples can be directly dispensed onto the micro-PAD card and the detection was achieved by the BTB indicator color change, from yellow to blue, after conversion of ammonium into ammonia and diffusion of the ammonia gas through a hydrophobic layer. The determination of total ammonia nitrogen in saliva using the developed micro-PAD card intended to be very simple method and operated without the need of laboratory equipment. A quantification limit of 11.3 NH4+mg L-1 and linear application range from up to 150 NH4+mg L-1 were obtained making it suitable for the expected concentrations of total ammonia nitrogen in human saliva. It was successfully applied to saliva samples and its validation obtained by comparison against a potentiometric method. The card is stable for at least 1 month making it ideal as a portable device for point-of-care diagnosis.N/
Flow-based method for the determination of biomarkers urea and ammoniacal nitrogen in saliva
Salivary urea and ammonium levels are potential biomarkers for chronic kidney disease. A fast and
efficient assessment of these compounds in the saliva of healthy and diseased individuals may be a useful
tool to monitor kidney function. Materials & methods: Ammonium ions were measured with an ammonia
selective electrode after conversion to ammonia gas. A urease reactor was incorporated in the manifold
to hydrolyze urea to ammonium, thereby providing values of ammonia from both urea and ammonium
ions in the sample. The accuracy of the method was assessed by comparison with a commercially available
kit for urea and ammonium determination. Conclusion: A sequential injection method for the biparametric
determination of salivary urea and ammonium employing a single sequential injection manifold
was successfully applied to samples collected from both healthy volunteers and chronic kidney disease
patients.info:eu-repo/semantics/publishedVersio