Validation of a low-cost lead hazard screening kit for the home environment.

The main sources of lead exposure for children occur in the home environment, yet no low-cost analytical methods exist to screen homes for lead hazards. Previously, an inexpensive (~$20), quantitative lead screening kit was developed in which residents collect soil, paint, and dust samples that are returned to a laboratory for lead analysis using X-ray fluorescence spectroscopy (XRF). This screening kit was initially validated in 2020; it was determined that in situ and ex situ XRF lead measurements on the same samples exhibited strong sensitivity, specificity, and accuracy.

Mitigating the impact of gelatin capsule variability on detection of substandard and falsified pharmaceuticals with near-IR spectroscopy.

Portable NIR spectrometers are effective in detecting authentic pharmaceutical products in intact capsule formulations, which can be used to screen for substandard or falsified versions of those authentic products. However, the chemometric models are trained on libraries of authentic products, and are generally unreliable for detection of quality problems in products from outside their training set, even for products that are nominally the same active pharmaceutical ingredient and same dosage as products in the training set. As part of our research directed at developing better non-brand-specific strategies for pharmaceutical screening, we investigated the impact of capsule composition on NIR modeling.

Metabolites in Urine that Interfere with the Sandell-Kolthoff Assay for Urinary Iodine.

The Sandell-Kolthoff (SK) assay is the main analytical method used to monitor population iodine nutrition in low- and middle-income countries. This assay can distinguish between populations that are iodine-deficient (median urinary iodine levels below 100 ppb), iodine-sufficient (median urinary iodine levels between 100 and 300 ppb), and iodine- excessive(median urinary iodine levels above 300 ppb). However, the analysis of urine samples with the SK reaction is technically challenging, partly because urine samples must be rigorously pretreated to remove interferents.