Patent ID: 6819408
Filing Date: 2004-11-16
Classification: G01N

Abstract:
A method for obtaining a liquid sample forming a monolayer of desired individual cells or particles for optical examination comprising:a) providing an apparatus comprising: a sample chamber comprising two containment walls, at least one of them being transparent for optical examination; at least one wall for holding said containment walls at a distance, and enclosing an interior space; a separation wall comprising at least a first separation channel that is of sufficient size and dimensions to allow desired cells or particles to pass while excluding larger cells or particles from passing, and a second separation channel, that is of sufficient size and dimensions to exclude desired cells or particles and larger cells or particles from passing while allowing the liquid component of the sample to pass freely, wherein the interior space of said sample chamber is divided into a first compartment and a second compartment by said separation wall, and whereby the distance between said containment walls in the second compartment in the chamber is sized so that individual desired cells or particles present in the sample will form a monolayer when the chamber is filled with the sample; a sample entrance into the first compartment; and a means for venting the sample chamber during filling; b) depositing a liquid sample into the sample entrance of said sample chamber; c) allowing the sample to flow from the sample entrance into the first compartment; d) allowing the sample to advance to the separation wall and to the separation channels therein; e) allowing desired cells or particles in the sample to pass through the first separation channel in the separation wall and allowing the liquid component of the sample to pass through the second separation channel in the separation wall; f) allowing the passed sample portion to continue advance until it reaches and stops at the end of the sample chamber; and g) obtaining a liquid sample forming a monolayer of desired individual cells or particles.