Systems and methods for detection of cells using engineered transduction particles

An apparatus, comprising:

• a housing defining a channel configured to receive a sample container, the housing defining a detection volume configured to place the channel in communication with a detector, the housing including a seal surface;
• and
• a shutter having a portion movably disposed within the housing between a first shutter position and a second shutter position, the shutter include a seal surface and an actuation portion, the actuation portion configured to engage a distal end portion of the sample container to move the shutter from the first shutter position to the second shutter position when the distal end portion of the container is moved towards the detection volume, the seal surface of the shutter and the seal surface of the housing configured to isolate the detection volume from the channel of the housing when shutter is in the first shutter position, the channel of the housing being in communication with the detection volume when the shutter is in the second shutter position.

An apparatus, comprising:

• a housing defining a channel configured to receive a sample container, the housing defining a detection volume configured to place the channel in communication with a detector, the housing including a seal surface;
• and
• a shutter defining a port configured to receive a light source, the shutter movably disposed within the housing between a first shutter position and a second shutter position, a seal surface of the shutter and the seal surface of the housing configured to isolate the detection volume from the channel of the housing when shutter is in the first shutter position, the port in communication with the detection volume when the shutter is in the first shutter position, the channel of the housing being in communication with the detection volume when the shutter is in the second shutter position, the port being isolated from the detection volume when the shutter is in the second shutter position.