Micronutrient deficiencies occur in limited resource environments, which in-turn presents a challenge in identifying afflicted populations in need of nutritional intervention. Researchers at Georgia Tech have published about a proof-of-concept biosensor technology that measures zinc levels in blood samples sans external laboratory equipment. The team modified E. coli bacteria such that bacterial pigmentation changes to purple, red, or orange indicating low, borderline, or normal concentrations based on the blood concentration of zinc. Genes producing the purple, red, and orange pigments were introduced into the bacteria via plasmids, and two native zinc transcriptional regulators were used to control the expression of the pigment-producing genes to generate three distinct pigments.
Integrated as a point-of-care diagnostic, an egg beater centrifuge would be used to separate the plasma, which would subsequently be placed in a test tube or plate containing the E. coli biosensors. The results indicating blood zinc levels would be read with the naked eye after an incubation period of 24 hours. The ultimate goal is to apply the biosensor technology to test for a wide range of micronutrients, including vitamins.
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Source: Georgia Institute of Technology…