173 documents found, page 1 of 18

Comparative studies of different signal acquisition systems in microfluidic pap...

The exponential growth of small, on-hand devices/sensors has been aligned with the increasing use of smartphones as detectors. However, smartphone detection may result in high variability of signal acquisition, due to differences in lighting conditions, consequently compromising accurate and reliable quantification. The use of smartphones for qualitative assessment (“yes/no” response) has been widely employed; ...

Chloride catalytic determination as potential tool to assess metal ion bioavail...

This paper focuses on the development of an environmentally friendly sequential injection (SI) method for the determination of chloride in water samples from dynamic water systems. Chloride quantification is highly relevant, as it may affect metal ion bioavailability and potential toxicity to the environment. The approach was established based on the catalytic reaction of chloride ions in the colorimetric react...

A microfluidic paper-based device for monitoring urease activity in saliva

Chronic Kidney Disease (CKD) is a disorder that affects over 10% of the global population, and that would benefit from innovative methodologies that would provide early detection. Since it has been reported that there are high levels of urease in CKD patients’ saliva, this sample is a promising non-invasive alternative to blood for CKD detection and monitoring. This work introduces a novel 3D µPAD for quantifyi...

A microfluidic paper-based analytical device for the determination of zinc(II) ...

In this work, an innovative microfluidic paper-based analytical device (?PAD) was developed for the quantification of zinc(II) in biological samples of non-invasive collection, namely children's urine. Zinc(II) in urine can be considered a biomarker of children's psychological development and mental conditions, as well as indicative of urinary tract diseases. The developed device is based on the colourimetric r...

A novel sampling strategy for metal ions determination in water: application to...

This work proposes a novel, portable, and reusable device for in situ water sampling, sample preparation, and analyte enrichment in a single step. For this purpose, a commercial cationic exchange resin (Chelex 100), was used to obtain a solid-phase extraction column for cadmium (II) retention and enrichment. The optimization of key parameters such as sample volume, reagents concentration, and flow-rate, was per...

Sequential injection system for multiparametric determination of copper (II), z...

Heavy metals such as copper, zinc, and manganese are commonly found in both natural and treated water sources. Although these metals are essential micronutrients, their accumulation even at low concentrations, can lead to serious health issues. Therefore, continuous and accurate monitoring of these elements in environmental and drinking water is crucial to ensure public safety. Solid Phase Extraction (SPE) is a...

Sequential injection lab-on-valve with bead injection for iron speciation in wa...

Innovative sampling strategies for trace metals analysis in water monitoring

Innovative microfluidic paper-based analytical device for the determination of ...

Zinc(II) is an important metal ion, present in the human body, that plays vital roles in biological processes, specifically in child growth, development, and improvement of cognitive behaviour. Its deficiency can cause serious health risks, which makes urinary zinc(II) analysis very relevant, as it is considered a biomarker of children’s psychological development and can even indicate urinary tract diseases. Zi...

Amostragem inteligente como abordagem expedita para monitorização de iões de me...