Reagent cartridge for detection of cells

A method, comprising:

• coupling a reagent module to a sample container such that an end surface of the reagent module covers a reaction chamber defined by the sample container, the reaction chamber containing a sample, the reagent module including a housing defining a reagent volume containing a reagent, the housing including a side wall defining a delivery path between the reagent volume and the reaction chamber when the reagent module is coupled to the reaction chamber;
• disposing, after the coupling, at least a distal end portion of the sample container into an instrument;
• and
• actuating the instrument to:
• produce a force on the reagent module to move at least the distal end portion of the sample container into a detection volume of the instrument;
• and
• manipulate, when the distal end portion of the sample container is in the detection volume, the reagent module to convey the reagent from the reagent volume into the reaction chamber via the delivery path within a time period between about 0.2 seconds and about 0.3 seconds.

An apparatus, comprising:

• a sample tube;
• a housing having a connection portion configured to mate with the sample tube, the housing further including a side wall defining an inner reagent volume of the housing, the housing further including a bottom end wall that separates the inner reagent volume from the sample tube when the housing is coupled to the sample tube, the bottom end wall comprising a puncturer having a sharp point, the bottom end wall further comprising a through hole that defines a delivery path between the inner reagent volume and the sample tube, the bottom end wall further including a plurality of protrusions projecting inwardly from a side surface of the through hole in the bottom end wall into the delivery path;
• a container within the inner reagent volume, the container containing a reagent and including a frangible portion;
• and
• an actuator having a plunger coupled to an engagement portion, the engagement portion configured to be manipulated to move the plunger within the inner reagent volume such that the puncturer pierces the frangible portion of the container to convey the reagent from the inner reagent volume into the sample tube via the delivery path.