Rapid Arsenite Assay developed with ProPlate® Multi-Well Chambers

IN ProPlate

It is always fascinating to learn how our customers take advantage of the versatility of Grace Bio-Labs’ ProPlate® Multi-Well Chambers. Initially designed to take full advantage of the multiplexing and high-throughput potential of microarray technology, ProPlates feature a compressible gasket applied on a polycarbonate upper chamber. Affixed on a glass slide they create the leak-proof wells necessary to multiply the number of experimental conditions that can be analyzed on a single microarray slide. Thanks to the creativity and resourcefulness of our customers, ProPlate’s use has been extended beyond its original purpose to be included in new and interesting experimental protocols.

For instance, in a recent study by Hung-Chi Y. et al., researchers used ProPlates to develop a new assay to detect arsenic in the environment. Arsenic contamination is a widespread health concern as inorganic arsenite (As(III)) is highly stable in the environment and extremely toxic to humans. The maximum concentration in drinking water allowed by the EPA and WHO is 10 ppb. Atomic absorption spectroscopy, inductively coupled plasma mass spectrometry, atomic fluorescence spectroscopy, and high-performance liquid chromatography currently deliver sensitive, reproducible, and reliable information about arsenic content in the environment. However, these techniques require a highly trained workforce, costly instrumentation, and complex sample preparation methods.

In this study, researchers developed a portable and rapid arsenic detection method. The assay is based on the use of a plasmonic silver chip (pAg). pAG chips display superior plasmonic properties and are a cheaper alternative to plasmonic gold chips. The steps involved in the construction of the pAG chip and assay development are summarized in the illustration below. A 64- well ProPlate chamber affixed on the chip created an ideal incubation chamber for the assay development. Cy7.5 fluorescent dyes conjugate with As (III) via their carboxylic groups were used for the fluorescence detection of As (III). The results showed a sensitivity over 4 orders of magnitude and a detection limit below 10 ppb for the assay, thus, describing a promising concentration screening method compatible with high-throughput analysis.

References

Yen HC, Kuo TR, Huang MH, Huang HK, Chen CC. Design of Fluorescence-Enhanced Silver Nanoisland Chips for High-Throughput and Rapid Arsenite Assay. ACS Omega. 2020;5(31):19771-19777. Published 2020 Jul 28. doi:10.1021/acsomega.0c02533