Publications in Scientific Journals:
K.A.J. Borthwick, W.T. Coakley, M.B. McDonnell, H. Nowotny, E. Benes, M. Gröschl:
"Development of a novel compact sonicator for cell disruption";
Journal of Microbiological Methods,
Ultrasound microbial cell disrupters operating at around 20 kHz are often physically large and, due to significant
heating, can be unsuitable for small sample volumes where biochemical integrity of the extracted product is required.
Development of a compact device based on a 63.5-mm diameter, 6.5-mm thick tubular transducer for rapid cell disruption
in small-volume samples in a high-intensity acoustic cavitation field with minimal temperature rises is described here.
Suspensions of Saccharomyces cerevisiae were exposed to cavitation for various times in the compact device and a 20-kHz
probe sonicator. Cell disruption was assessed by protein release and by staining. Yeast cell disruption was greater in the
novel 267-kHz sonicator than in the 20-kHz probe sonicator for the same exposure time. A 1-dimensional (1-D) transfer
matrix model analysis for piezoelectric resonators was applied to an axial cross-section of the tubular sonicator to predict
frequencies of mechanical resonance in the sample volume associated with maximum acoustic pressure. Admittance
measurements identified frequencies of electrical resonance. Ultrasonic cavitation noise peaks were detected by a
hydrophone at both the mechanical and electrical resonances. Cell breakage efficiency was twice as great in terms of
protein released per dissipated watt at the mechanical resonance predicted by the model, compared to those at the electrical
resonance frequencies. The results form a basis for rational design of an ultrasound cell disruption technique for smallvolume
D 2004 Elsevier B.V. All rights reserved.
Keywords: Bacterial disruption; Microbial disruption; Cell wall; Immunoassay
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Created from the Publication Database of the Vienna University of Technology.