Separation of Cryptosporidium parvum via viability status using Dielectrophoretic Microfluidics

Cryptosporidium spp. is a waterborne protozoan pathogen that causes gastrointestinal disease and remains responsible as the second leading cause of death in children under the age of 5 after pneumonia with nearly half a million deaths worldwide every year. Current water quality testing methods are unable to determine species or viability and require lengthy protocols such as excystation assays or Propidium Iodide testing. Furthermore, these tests can require large numbers of oocysts. Dielectrophoresis is a technique which involves the usage of a non-uniform electric field to impart force on particles in a controlled manner. When combined with the emerging field of Microfluidics, Dielectrophoresis provides an effective means to separate various cells based on inherent properties. We present a device which has the capability to separate Cryptosporidium parvum, a major cause of gastroenteritis in humans, based on its infective status. The device was tested with infective and non-infective oocysts separately and optimal conditions were found. A mixed sample containing 50% infective and 50% non-infective oocysts was prepared and it was shown that the device was capable of separating the two groups with an efficiency of 100%.