Acoustic lysis of vegetative bacterial cells: Method and device development

A critical problem of many pathogen detection assays is the availability of intracellular protein and deoxyribonucleic acid (DNA). Acoustic lysis of suspended vegetative bacterial cells in a microfluidic system offers several advantages over conventional lysis techniques. The intracellular proteins and DNA are released and available for detection. A novel acoustic lysing alternative technique to the existing lysing methods for sample preparation and lysis step is proposed. We report here an efficient lysis device that uses acoustic excitation for performing lysis of Gram-positive and Gram-negative vegetative cells and has a high yield in a short amount of time. We also verified the condition of released protein since one of the major uses of vegetative cells lysis is for protein expression studies. Fluorimetry and flow cytometry were used to assess the degree of damage induced on the cells by the actual lysis method. The acoustic device allows the delivery of proteins in a non-denatured form, without adding chemicals, particles or other substances (e.g. enzymes) that could complicate the process or the detection procedure. The lysis device operates at low power (50-400 mW) and short time (3 min) and has high efficiency in comparison to current lysis standards (>85% vs. 12-50%).