Alveolar breath collection apparatus
An apparatus for collecting volatile organic compounds from a gas sample such as alveolar breath or room air comprises an exhaust portion having at least a flow measuring device, and a discriminating device for distinguishing between alveolar and non-alveolar breath. The apparatus further comprises a collection portion distinct from and parallel with the exhaust portion having at least a collection component for receiving and concentrating gas samples within a collection chamber and a sampling component having a plurality of sampling devices for receiving the concentrated gas sample from the collection chamber and isolating VOCs contained in the gas sample. The collection chamber is compressible via a drive mechanism for precisely actuating the chamber to draw a gas sample into the collection chamber and circulating the sample to the sampling devices. Use of a drive mechanism enables the exhaust portion to be distinct from the collection portion, thereby mitigating cross-contamination therebetween.
1. An apparatus for collecting a gas sample and sampling volatile organic compounds from the collected gas sample, the apparatus comprising:
a gas inlet for receiving the gas sample;
a gas collection and sampling portion in fluid communication with the gas inlet via a gas collection line extending from the gas inlet, the gas collection and sampling portion having
at least a first gas collection portion, positioned on a first branch of the gas collection line, the gas collection portion forming a gas collection chamber for receiving the portion of the gas sample, the chamber formed to receive a reciprocating piston therein, the piston operably connected to a drive mechanism for actuating the piston within the chamber between a first compressed position and a second decompressed position, to draw at least a portion of the gas sample into the chamber, and in reverse between the second decompressed position and the first compressed position, to expel at least a portion of the gas sample stored within the chamber, and
at least one gas sampling portion, positioned on a second branch of the gas collection line, for receiving the portion of the gas sample expelled from the chamber from the gas collection portion, the gas sampling portion formed to provide at least one gas sampling device configured to capture the volatile organic compounds from the portion of the gas sample received therein; and
an exhaust portion extending, via an exhaust line, from the gas collection line, the exhaust line having an outlet portion with unidirectional flow away from the gas collection line, the exhaust portion having
a flowmeter, positioned on the outlet portion of the exhaust line, for measuring the volume of the gas sample, and
a gas monitoring device fully positioned on the outlet portion of the exhaust line and spaced from the gas collection line, the gas monitoring device being configured to measure and monitor at least one physical characteristic of the gas sample.
2. The apparatus of claim 1 , wherein the gas monitoring device is a capnometer.
3. The apparatus of claim 1 , wherein the exhaust portion further comprises at least one venting gas outlet for venting some or all of the gas sample from the apparatus.
4. The apparatus of claim 1 , wherein the exhaust portion further comprises a pump and at least one pump gas outlet, and wherein the pump is controllably activated to draw ambient air through the exhaust line and out at least one second gas outlet, to flush the exhaust line.
5. The apparatus of claim 1 , wherein the apparatus further comprises at least one auxiliary gas inlet port positioned to allow an inflow of ambient air into the apparatus when there is a negative pressure therein.
6. The apparatus of claim 1 , wherein the drive mechanism comprises a motor.
7. The apparatus of claim 1 , wherein the at least one gas sampling device comprises at least one thermal desorption tube.
8. The apparatus of claim 7 , wherein the thermal desorption tubes are configured to enable at least nitrogen, oxygen, water, and carbon dioxide from the at least one gas sample to pass through.
9. The apparatus of claim 1 , wherein the gas collection and sampling portion further comprises an ambient air component having a first ambient air intake to collect and sample ambient air from the environment.