Microdroplet based disposable sensor patch for detection of α-amylase in human blood serum Bhattacharjee, Mitradip Middya, Sagnik Escobedo Araque, Pablo Chaudhuri, Joydip Bandyopadhyay, Dipankar Dahiya, Ravinder Concentration of α-amylase in human serum is a key indicator of various pancreatic ailments and an affordable point-of-care detection of this biomarker can benefit millions suffering from these diseases. In view of this situation, we report the development of a flexible patch-sensor, which simply requires a microdroplet of aqueous starch-FeSO4 solution to detect α-amylase in serum. The detection is achieved through the generation of mixing vortices (~12 rpm) inside the droplet with the help of an imposed thermal gradient. Such vortices due to Marangoni and natural convections are found to be strongest at an optimal temperature difference of ~18 °C – 23 °C across the droplet which in turn facilitate mixing and promote the specific starch-amylase enzymatic reaction. Subsequently, the large (~80%) variation in the electrical resistance across the droplet is correlated to detect the level of the α-amylase in the analyte. Importantly, the sensor can detect even in the limits of 15–110 units/liter. Further, the sensitivity of flexible sensors is ~8.6% higher than the non-flexible one. Interestingly, the sensitivity of the proposed sensor has been nearly three-times than the previously reported optical ones. The results of patch-sensor match very closely with the standard path-lab tests while detecting unknown level of amylase in serum. The prototype has shown significant potential to translate into an affordable device for the real-time detection and easy prognosis of pancreatic disorders. 2026-02-13T09:59:24Z 2026-02-13T09:59:24Z 2020-10-01 journal article Mitradip Bhattacharjee, Sagnik Middya, Pablo Escobedo, Joydip Chaudhuri, Dipankar Bandyopadhyay, Ravinder Dahiya, Microdroplet based disposable sensor patch for detection of α-amylase in human blood serum, Biosensors and Bioelectronics, Volume 165, 2020, 112333, ISSN 0956-5663, https://doi.org/10.1016/j.bios.2020.112333. https://hdl.handle.net/10481/110965 10.1016/j.bios.2020.112333 eng http://creativecommons.org/licenses/by-nc-nd/4.0/ embargoed access Attribution-NonCommercial-NoDerivatives 4.0 Internacional