Novel Reduced Pressure-Balance Syringe for Chromatographic Analysis
Bret Windom, Thomas J. Bruno
When withdrawing a fluid sample from an apparatus at reduced pressures for additional chromatographic analyses, a gas tight plunger syringe proves ineffective as it does not create a substantial pressure differential to pull a fluid from a reduced pressure environment. Resulting from motivation to analyze distillate fractions from a reduced pressure advanced distillation curve (ADC) apparatus, a device was developed allowing one to withdraw precise amounts of sample from an apparatus operating at sub-ambient pressures. The new device uses an external vacuum source to evacuate a syringe barrel, extracting fluids from a chamber at pressures as low as 0.5 kPa. To demonstrate the operation of the newly developed device, 10 υl of distillate fraction from the reduced pressure ADC apparatus were withdrawn and analyzed by gas chromatography mass spectrometry. Distillate extraction and analyses were performed on two fluids, a predefined validation mixture and commercial soy based biodiesel fuel. The new device is not limited to reduced pressure distillations and may be useful for a variety of applications in which further chemical/compositional analyses are desired on a fluid contained in a reduced pressure environment.