MUMS: Mobile Urinalysis for Maternal Screening

Pregnant women in low-income communities often lack access to the necessary healthcare for successful births. This is frequently due to the high costs of medical care, the remote location of patients, and the infrequency of primary care medical visits. To address this inequity, we have created a mobile application and imaging unit that allows for the low-cost implementation of urinalysis testing, which will aid in the detection of warning signs for prenatal health risks. From a single photo taken with a tablet camera, our application digitizes the results of a standard urinalysis test strip, displays the test results, and tracks the patient test histories. Using early, affordable urinalysis, we can increase the rates early detection, intervention, and successful pregnancies. Our results have shown that our solution can accurately estimate the concentrations of biological compounds found in urine when compared to visual approximations of color comparison charts. Our device is not only more efficient than the alternative, but also more efficient at screening for and detecting potentially fatal health conditions in pregnant women. Ultimately, our solution is a frugal and mobile urinalysis alternative that can feasibly be implemented in rural communities in order to increase early detection of pregnancy complications, allow for early intervention, and improve the probability of successful pregnancies

Urine Tests for Diagnosis of Infectious Diseases and Antibiotic-Resistant Pathogens

The relation between disease and urine was recognized by physicians since the earliest civilization BC. Urine is considered an ideal diagnostic specimen for its noninvasive and easy method of collection. Urinalysis encompasses a wide range of tests, which includes a variety of chemical tests, urine microscopy, bacterial cultures, and molecular tests. Importantly, urine tests can diagnose patients with antibiotic-resistant urinary tract infections (UTI), directly from urine and/or bacterial culture. This chapter summarizes the most common urine tests in the infectious disease field, with a special focus on diagnosing UTI and characterizing their antibiotic resistant. In addition to describing the advantages and limitation of these tests, the chapter explores the promising emerging technologies and methods in this field. This chapter is beneficial for scientists and healthcare workers in the field

Measurement of proteinuria

In pregnancy, there is a focus on measurement of proteinuria as it has been regarded as critical to the diagnosis of pre-eclampsia, the most dangerous of the hypertensive disorders of pregnancy. However, it is increasingly recognised that proteinuria is not essential for the diagnosis of pre-eclampsia, which can be based on other end-organ complications (such as elevated liver enzymes). Although heavy proteinuria has been linked with an increased risk of stillbirth in a ‘signs and symptoms only’ model of maternal risk (i.e., miniPIERS), we lack the ability to identify a level of proteinuria above which maternal and/or perinatal risk is heightened. Therefore, at present, we rely on the detection of proteinuria that exceeds what is normally excreted by healthy pregnant women. Proteinuria detection methods are also a matter of keen debate, with all available methods having advantages and disadvantages.Publisher PD

Microfluidic paper-based analytical device (μPAD) for rapid detection of cadmium in river water

In recent years, the issue of contamination of water with heavy metal ion is never-ending, thus seeking extensive attention from all over the world. Heavy metal above a threshold limit is toxic to humans as well as the environment. Therefore, a very promising method using μPAD is presented for the rapid determination of Cd at an ultra-trace level using 1,5-diphenylthiocarbazone (dithizone) as colorimetric reagent (λ=500 nm) in aqueous solution. The mixture turns from brownish-red to orange colour in the presence of Cd. The use of paraffin wax with the handheld rubber stamp was demonstrated for the detection of Cd using colorimetric detection. The paraffin wax was used onto the filter paper to create a hydrophobic barrier for fluidic channels. The μPAD was fabricated within 10 min and provided high reproducibility and stability. The rubber stamping method provides a simple, rapid and cost-effective in fabrication of uPAD. The calibration curves were constructed for developed method of μPAD. The linear coefficient (R2) was 0.9538 and the detection limits of Cd ion using μPAD was 3.87 ppm. The results demonstrate that the detection limits obtained for both methods were higher than the permissible limit of Cd which is 0.005 ppm. These methods were reported to be less sensitive for ultra-trace metal such as Cd. However, for real sample analysis, the recovery of Cd in the water samples was measured as 82.5% using μPAD. It has good recovery value. To conclude, the fabricated μPAD can be used as screening test which one of the most vital steps in paper-based assays to identify the presence of analyte but confirmation step is required for further analysis using the sophisticated instruments

Holographic Point-of-Care Diagnostic Devices

Developing non-invasive and accurate diagnostics that are easily manufactured, robust and reusable will provide monitoring of high-risk individuals in any clinical or point-of-care environment, particularly in the developing world. There is currently no rapid, low-cost and generic sensor fabrication technique capable of producing narrow-band, uniform, reversible colorimetric readouts with a high-tuneability range. This thesis aims to present a theoretical and experimental basis for the rapid fabrication, optimisation and testing of holographic sensors for the quantification of pH, organic solvents, metal cations, and glucose in solutions. The sensing mechanism was computationally modelled to optimise its optical characteristics and predict the readouts. A single pulse of a laser (6 ns, 532 nm, 350 mJ) in holographic “Denisyuk” reflection mode allowed rapid production of sensors through silver-halide chemistry, in situ particle size reduction and photopolymerisation. The fabricated sensors consisted of off-axis Bragg diffraction gratings of ordered silver nanoparticles and localised refractive index changes in poly(2-hydroxyethyl methacrylate) and polyacrylamide films. The sensors exhibited reversible Bragg peak shifts, and diffracted the spectrum of narrow-band light over the wavelength range λpeak ≈ 500-1100 nm. The application of the holographic sensors was demonstrated by sensing pH in artificial urine over the physiological range (4.5-9.0), with a sensitivity of 48 nm/pH unit between pH 5.0 and 6.0. For sensing metal cations, a porphyrin derivative was synthesised to act as the crosslinker, the light absorbing material, the component of a diffraction grating, as well as the cation chelating agent. The sensor allowed reversible quantification of Cu2+ and Fe2+ ions (50 mM - 1 M) with a response time within 50 s. Clinical trials of a glucose sensor in the urine samples of diabetic patients demonstrated that the glucose sensor has an improved performance compared to a commercial high-throughput urinalysis device. The experimental sensitivity of the glucose sensor exhibited a limit of detection of 90 µM, and permitted diagnosis of glucosuria up to 350 mM. The sensor response was achieved within 5 min and the sensor could be reused about 400 times without compromising its accuracy. Holographic sensors were also tested in flake form, and integrated with paper-iron oxide composites, dyed filter and chromatography papers, and nitrocellulose-based test strips. Finally, a generic smartphone application was developed and tested to quantify colorimetric tests for both Android and iOS operating systems. The developed sensing platform and the smartphone application have implications for the development of low-cost, reusable and equipment-free point-of-care diagnostic devices

Antecedents of renal disease in aboriginal children (ARDAC study)

The aim of this study was to identify implicit cognitive predictors of aggressive behavior. Specifically, the predictive value of an attentional bias for aggressive stimuli and automatic association of the self and aggression was examined for reactive and proactive aggressive behavior in a non-clinical sample (N = 90). An Emotional Stroop Task was used to measure an attentional bias. With an idiographic Single-Target Implicit Association Test, automatic associations were assessed between words referring to the self (e.g., the participants' name) and words referring to aggression (e.g., fighting). The Taylor Aggression Paradigm (TAP) was used to measure reactive and proactive aggressive behavior. Furthermore, self-reported aggressiveness was assessed with the Reactive Proactive Aggression Questionnaire (RPQ). Results showed that heightened attentional interference for aggressive words significantly predicted more reactive aggression, while lower attentional bias towards aggressive words predicted higher levels of proactive aggression. A stronger self-aggression association resulted in more proactive aggression, but not reactive aggression. Self-reports on aggression did not additionally predict behavioral aggression. This implies that the cognitive tests employed in our study have the potential to discriminate between reactive and proactive aggression

Hyphenating paper-based biosensors with smartphones

Paper-based biosensors are small, lightweight, inexpensive diagnostic devices made from paper. These characteristics enable these devices to be popular candidates for point-of-care testing in resource poor settings. They are a versatile platform that has a variety of uses, including clinical diagnostics, infectious disease monitoring, environmental sampling, and food safety screening. Paper-based biosensors are robust and reliable diagnostic methods; they have been in use for over 40 years and are constantly evolving to meet ever more complicated diagnostic criteria. Earlier iterations include the dipstick assay and the lateral flow assay. In the dipstick assay, chemical reactions cause the paper to change colour when wet; the lateral flow assay moves fluid across the paper by simple diffusion or capillary action to produce simple colorimetric biochemical reactions. More recently, microfluidic pads have incorporated lab-on-a-chip principles: printed flow channels, 3-dimensional folding, and even (paper-based) switches to allow more complicated chemical and biochemical reactions. This chapter will explore the different types of paper-based biosensor, their designs and uses. Further, it will explore smartphones as an adjunct device capable of enhancing the paper-based biosensors' capabilities, due to the smartphone's ubiquity, high-powered camera, onboard processing, and digital connectivity