The use of microfluidics and dielectrophoresis for separation, concentration, and identification of bacteria

ABSTRACT Traditional bacterial identification methods take one to two days to complete, relying on large bacteria colonies for visual identification. In order to decrease this analysis time in a cost-effective manner, a method to sort and concentrate bacteria based on the bacteria’s characteristics itself is needed. One example of such a method is dielectrophoresis, which has been used by researchers to separate bacteria fro m sample debris and sort bacteria according to species. This work presents variations in which dielectrophoresis can be performed and their associated drawbacks and benefits specifically to bacterial identification. In addition, a potential microfluidic design will be discussed. Keywords: Dielectophoresis, microfluidics, cell sorting, Raman spectroscopy, bacterial identification 1. INTRODUCTION The standard method to identify bacteria is the use of an array agar media and associated antibiotics. Depending on bacterial growth among the array, the bacteria can be identified. This method is entirely dependent on the growth rate of the bacteria. Typically, bacteria will take one to two days to grow to colonies large enough for visual identification, while others may take weeks. For time sensitive illnesses, this lag in analysis time is unacceptable and has been the motivation for many researchers to find a faster methods to identify bacteria. Common methods to decrease the analysis time of bacteria include techniques such as po lymerase chain reaction (PCR)