Case Study - Home, Beauty, and Health
Measurement of volatiles from applied skin lotions
The objective for this project was to determine what compounds were uniquely generated from skin treated with lotion. Samples (conditioned Twister bars exposed to skin headspace) were received from client and stored under refrigeration until analyzed by a GC-MSD equipped with Gerstel components including: MPS2, TDU, CIS, and MACH. Twister bars were placed into TDU tubes and heated to 300oC for 4 minutes inside a thermal desorption unit (TDU). The TDU transfer temp was 300oC and operated in splitless mode with purge time 1.00. Volatiles were swept onto a cryo-cooled (LN2) inlet liner at -130oC (CIS4 liner in split mode 30:1). The liner contained glass beads for increased adsorption. The liner was heated to 300oC for 3 min holding time and volatiles were transferred to the analytical DB-5 MACH column. Column heating conditions, two ramp rates, were: held at 35oC for 5 min then 4oC/min to 220oC for 0 min holding time and 7°C/min to 300°C for 1 min holding time. Total ion chromatogram time was 63.68 min. Conditions were ramped pressure with initial pressure 46.9 kPa for 5 min then 1.6 kPa/min to 120.0 kPa for 0 min and 2.8 kPa/min to 151.4 kPa for 1 min. MSD transfer line temperature 280oC. Scan parameters were 35-350 a.m.u. The DB-5 capillary column utilized was a 30m x 0.25mm I.D. x 0.25µm film thickness. Components were identified by matching spectra with a Wiley 2007 library.
Measurement of organic impurities in water
Approximately 10g of liquid sample (sample A, B, C, D, E, F, G, H, I and J) were placed in 40mL clear vials and limonene was extracted using SBSE, or Twister, at room temperature for 90min. Twisters were heated to 280oC for 3 minutes inside a thermal desorption unit (TDU). The TDU transfer temp was 280oC and operated in splitless mode with purge time 1.00min. The target volatile generated during thermal desorption of Twister bar were swept onto a cryo-cooled (LN2) inlet liner at -90oC (CIS4 liner in split mode 20:1). The liner contained glass beads for increased adsorption. The liner was heated to 280oC for 3min and volatiles were transferred to the analytical DB-5 MACH column. Column heating conditions were: initial temp. at 35oC for 5 min then 10oC/min to 135oC for 0min, and the second ramp rate 100oC/min to final temp. at 250oC for 3min. Total ion chromatogram time was 19.15min. Conditions were ramped pressure with initial pressure 6.80 psi for 5 min then 0.57 psi/min to 12.50 psi, the second ramp pressure 5.74 psi/min to 19.10 psi for 3 min. MSD transfer line temperature 280oC. Scan parameters were 35-350a.m.u. The DB-5 capillary column utilized was a 30m x 0.25mm I.D. x 0.25µm film thickness. The component were extracted by m/z 136 and identified by matching spectra with a Wiley 2007 library.
Data analysis was conducted by integrating total ion chromatograms with Agilent ChemStation and copying selected peak areas to an Excel spreadsheet.
|
