Membrane-assisted purification

Inventors

Prisbrey, Landon • Blackmore, Elise • Hance, Kenneth R. • Metzger, Steven W. • Marshall, Kevin

Assignees

ElitechGroup Inc

Abstract

Methods and systems for purifying one or more microbial cells and/or viruses from a biological sample are provided. The biological sample is added to a well disposed in a medium. A potential is applied across the medium to cause the contaminants to enter one or more walls of the well, and retain the microbial cells and/or viruses in the well. The microbial cells and/or viruses can be removed from the well, and optionally adhered or fixed to a surface, or detected. In one embodiment, the microbial cells and/or viruses are retained in the well by embedding in the medium. The medium including the embedded microbial cells and/or viruses may be excised or otherwise removed and transferred to a glass slide or other solid surface. In some examples, a biological sample containing contaminants and one or more microbial cells is introduced to a well disposed in a porous filter medium, wherein the porous filter medium includes pores smaller than the one or more microbial cells, thereby preventing the one or more microbial cells from entering the porous filter medium.

Core Innovation

The invention provides a method of purifying one or more microbial cells in a biological sample using membrane-assisted purification (MAP). A biological sample containing contaminants and one or more microbial cells is added to a well disposed in a porous filter medium, and the porous filter medium comprises pores smaller than the one or more microbial cells, thereby preventing the one or more microbial cells from entering the porous filter medium.

A buffer disposed in one or more reservoirs adjacent to the porous filter medium is used to initiate diffusion. An electrical potential is applied across the porous filter medium to cause the contaminants to enter the porous filter medium through one or more walls of the well, while retaining the one or more microbial cells in the well. The purified one or more microbial cells are then removed from the well.

The disclosed approach is implemented with system configurations that include a well in a medium, a porous filter medium adjacent to buffer reservoirs, and electrodes arranged to apply the electrical potential. The disclosure also specifies selectable pore sizes and porous filter medium materials, and describes optional use of tangential flow and repeated cycles in the MAP process. In example embodiments, the method is adapted for embedding in the medium and excision of the medium/well for staining and detection, including Gram staining.

Claims Coverage

The independent claim set is grounded in purifying microbial cells by combining pore-size exclusion in a porous filter medium with buffer diffusion and an applied electrical potential to drive contaminants into the porous medium while retaining the microbial cells in the well. The independent inventive concept includes at least three core inventive features: a well disposed in a porous filter medium with pores smaller than microbial cells, contacting with an adjacent reservoir buffer to initiate diffusion, and applying an electrical potential to move contaminants into the porous filter medium while retaining the microbial cells in the well, followed by removal of the microbial cells.

Across the independent inventive concept, the claims require pore-size exclusion in a porous filter medium combined with buffer diffusion from adjacent reservoirs and an applied electrical potential that drives contaminants into the porous medium while retaining microbial cells in the well, followed by removal of the microbial cells. Dependent claim refinements in the provided material further specify example pore sizes, electrical potential timing, porous filter medium materials, and optional behaviors such as switching field polarity and mixing-related limitations.

Stated Advantages

Documented Applications

No documented applications found