Devices and methods for quantifying nitric oxide
The present disclosure relates to methods, devices, and systems for measuring nitric oxide released from a material. For example, a method of measuring nitric oxide release from a material can include introducing a continuous flow of a carrier gas into a sample holding chamber via a carrier gas inlet at an effective flow rate, introducing an amount of the nitric oxide releasing material into the sample holding chamber via a separate sample inlet to contact the continuous flow of the carrier gas, directing the carrier gas and released nitric oxide out of the sample holding chamber via a nitric oxide outlet toward a nitric oxide detector, and quantifying an amount of released nitric oxide using the nitric oxide detector.
1 . A method of measuring nitric oxide release from a material, comprising:
introducing a continuous flow of a carrier gas into a sample holding chamber via a carrier gas inlet at an effective flow rate;
introducing an amount of a nitric oxide releasing material into the sample holding chamber via a sample inlet to contact the continuous flow of the carrier gas, wherein the nitric oxide releasing material releases nitric oxide into the continuous flow of the carrier gas at a nitric oxide release rate;
directing the carrier gas and the released nitric oxide out of the sample holding chamber via an outlet to a nitric oxide detector while the nitric oxide releasing material is held in the sample holding chamber; and
measuring a concentration of released nitric oxide in the continuous flow of the carrier gas using the nitric oxide detector while the nitric oxide releasing material continues to release nitric oxide in the sample holding chamber.
2 . The method of claim 1 , wherein the effective flow rate is from about 0.025 liters per minute (L/min) to about 10 L/min.
3 . The method of claim 1 , further comprising reducing oxygen content within the sample holding chamber by one or more of: applying a vacuum to the sample holding chamber, flushing the sample holding chamber with an inert gas, or a combination thereof, or purging the sample holding chamber of oxygen.
4 . The method of claim 1 , wherein the carrier gas is introduced into the sample holding chamber through a plurality of carrier gas inlets simultaneously.
5 . The method of claim 1 , wherein introducing the carrier gas is performed either prior to or after introducing the nitric oxide releasing material.
6 . The method of claim 1 , wherein a first component of the nitric oxide releasing material is introduced prior to introducing the carrier gas and a second component of the nitric oxide releasing material is introduced after introducing the carrier gas.
7 . The method of claim 1 , wherein the nitric oxide releasing material comprises a liquid, a semi-solid, a gel, or a cream.
8 . The method of claim 1 , wherein the nitric oxide releasing material is introduced in an amount of from about 1 microliter (μl) to about 1000 milliliters (ml).
9 . The method of claim 1 , wherein nitric oxide is either:
directed toward the nitric oxide detector via either a sidestream channel or a mainstream channel;
sampled from the mainstream channel and transferred to the nitric oxide detector for analysis; or
sampled directly from the sample holding chamber and transferred to the nitric oxide detector for analysis.
10 . The method of claim 1 , wherein nitric oxide is quantifiable at a level of 10 parts per billion or lower.