This work presents the development and validation of novel thin film solid phase micro extraction (TF-SPME) based standard gas generating vials suitable for repeatable generation of gaseous standards for GC-MS analysis and quality control. The vials were developed using carbon mesh membranes loaded with pure polydimethylsiloxane (PDMS), divinylbenzene (DVB/PDMS), hydrophilic-lipophilic bal-ance (HLB/PDMS), and carboxen (Car/PDMS) sorbents that were then spiked with modified McReynolds standards including benzene, 2-pentanone, 1-nitropropane, pyridine, 1-pentanol, octane, dodecane, and hexadecane. Sorbent strength was determined to follow the aforementioned order, with pure PDMS presenting the weakest sorption capabilities and Car/PDMS the strongest. While the weaker, pure PDMS based gas generating vials transferred an instrument-overloading amount of McReynolds probes to the 1.1 mm DVB/PDMS SPME arrows used for extraction, vials prepared using Car/PDMS TF-SPME as a sorbent failed to provide consistently detectable amounts of analytes less volatile than 1-nitropropane. The DVB/PDMS and HLB/PDMS based vials were found to maintain optimal sorption capabilities for the tested analytes, providing a sorption strength strong enough to not exhibit any depletion in 10 replicate runs, while still delivering a consistent amount of all the regular McReynolds components. Moreover, with intra-vial%RSDs of 5% or less for all analytes tested, these HLB and DVB vials were found to deliver very good repeatability. After purposely submitting vials to 200 accelerated depletion extractions (1.1 mm DVB/PDMS arrow at 55 degrees C for 3 min), vials prepared with DVB/PDMS were found to deplete by 33%, 38%, 34%, 33%, 40%, and 33% while vials prepared with HLB/PDMS were found to deplete by 21%, 16%, 12%, 31%, 16% and 0% for benzene, 2-pentanone, 1-nitropropane, pyridine, 1-pentanol, and octane, respectively. When user typical extractions conditions were used instead (50/30 mu m DVB/Car/PDMS SPME fiber at 35 degrees C for 1 min), no depletion could be observed from the HLB/PDMS based vial while%RSDs ranged from 1.1-3.0% after the 300 extraction/desorption cycles. Finally, in efforts to demonstrate its real world applicability, the DVB/PDMS vial was used to evaluate the inter-fiber repeatability of commercial DVB/PDMS SPME arrows, with results demonstrating that arrows from a single package were statistically similar (ANOVA at 95% confidence). (c) 2020 Elsevier B.V. All rights reserved. (AU) |