IFEG   20353
INSTITUTO DE FISICA ENRIQUE GAVIOLA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Geometrical optimization for notility-based microorganisms concentrator and sorter devices
Autor/es:
I. BERDAKIN; Y. JEYARAM; A. V. SILHANEK; A. GUIDOBALDI; L.C. GIOJALAS; C. A. CONDAT; V. I. MARCONI
Lugar:
Córdoba
Reunión:
Workshop; Latin American Workshop on Nonlinear Phenomena; 2013
Institución organizadora:
FaMAF
Resumen:
The use of soft lithography to build asymmetric microsubstrates makes it possible to control microorganisms motion and promises new and interesting applications in health industry and biotechnology. In this work, we investigate two ways in which these ratchet devices can be employed. First we show, experimentally and numerically, that it is possible to accumulate sperm cells in a region of space of our choice. Second, we study the most efficient way to sort out different subpopulations in a mixed culture of E. coli bacteria, that differ by their specific swimming strategies. In both cases, we develop models that incorporate the most relevant phenomenological aspects of the cellular motion using realistic parameters found in experiments, and integrate the equations of motion through molecular dynamics algorithms [1]. For E. coli, we study the  diffusion properties of each subpopulation along the sorter and define a purity parameter for the extraction of each strain as a function of position. We obtain in this way a set of optimized parameters of the array geometry that maximizes the sorting efficiency of the device for different subpopulations. Our results show remarkably that it is possible to sort bacteria with 100% purity even for slightly different strains in experimentally reasonable times. We also conclude that a key element to consider when working with spermatozoa is that their interactions with walls and corners is remarkably different from run and tumble bacteria, because sperm cells tend to get trapped in acute angles