Identifying Hypocalcemia in Dairy Cattle by Combining 3D Printing and Paper Diagnostics
Art Matthew Mamaril, Dalton Lee Glasco, Francisco A. Leal Yepes, Jeffrey G. Bell
Abstract
This paper describes the design, fabrication, and validation of a paper-based diagnostic device for the rapid diagnosis of hypocalcemia in dairy cattle at the point-of-care (POC). The device incorporates a 3D printed calcium ion-selective membrane (ISM) as the sensing element for free—unbound—calcium in real bovine whole blood samples. With a linear response range of 100 mM to 97.7 μ M, the sensor covers the clinically relevant concentrations of Ca 2+ associated with both healthy cattle as well as those suffering from hypocalcemia. The components of the Ca 2+ ion-selective electrodes were successfully translated to a paper-based device to provide a sensing platform that is simple to use, disposable, and low-cost, and is therefore well-situated for applications at the POC. The paper-based calcium sensor showed a Nernstian response between 10 mM and 100 μ M and required only 12 μ l of sample to perform a measurement, which can be accomplished in less than two minutes without the need for time-consuming separation steps. The performance of the paper-based Ca 2+ sensor was validated using the commercially available epoc ® Blood Analysis System, which provided results within 5% of the data obtained with 3D printed Ca 2+ -ISM integrated paper-based device.