Pulsed Discharge Helium Ionization Detector for Highly Sensitive Aquametry

Area of Science:

• Analytical Chemistry
• Sensor Technology

Background:

• Accurate trace moisture quantitation is vital across medical, civilian, and military sectors.
• Existing aquametry methods face limitations in sample volume, reactivity, interferences, and instrument practicality.

Purpose of the Study:

• To introduce and validate a pulsed discharge helium ionization detector (PDHID-D2) for sensitive trace moisture analysis.
• To demonstrate the PDHID-D2's advantages over current aquametry technologies.

Main Methods:

• Utilized a compact pulsed discharge helium ionization detector (PDHID-D2) with a volume of approximately 196 cm³.
• Quantitated trace moisture in small liquid and gas samples (0.2 - 5.0 μL).
• Assessed sensitivity, linearity, and speed of the PDHID-D2 method.

Main Results:

• Achieved high sensitivity with a limit of detection of 0.047 ng (26 ppm) for liquid samples.
• Demonstrated excellent linearity (r² > 0.99) and rapid analysis (< 2 min).
• Reported a relative humidity sensitivity of 0.22% (61.4 ppmv) and < 1 ng LOD for gaseous samples, outperforming competing technologies.

Conclusions:

• The PDHID-D2 provides a highly sensitive, rapid, and cost-effective solution for trace moisture quantitation.
• Its small size, low power needs, and affordability enhance its applicability in various fields.
• This technique offers superior performance without the drawbacks of conventional aquametry methods.