Cis vaccenic acid

Oleic acid (FA 18:1 (Δ9)), cis-vaccenic acid (FA 18:1 (Δ11)), linOleic acid (FA 18:2 (Δ9, Δ12)), γ-linolenic acid (FA 18:3 [Δ6, Δ9, Δ12], GLA), linolenic acid (FA 18:3 (Δ9, Δ12, Δ15), ALA) and 3-chloroperbenzoic acid (mCPBA) were purchased from Sigma-Aldrich (St Louis, MO, USA). Acetonitrile, isopropanol, formic acid, and water in Optima grade were purchased from Fisher Chemical (Fair Lawn, NJ, USA). Nitrogen gas for purging the sample stage enclosure was purchased from Arc3 Gases (Raleigh, NC, USA).

Oleic acid (analytical standard) was purchased from Supelco (Bellefonte, PA). Palmitic acid (≥ 99%), stearic acid (Grade 1, ≥ 98.5%, capillary GC), palmitoleic acid (98.5%, GC), cis-vaccenic acid (≥ 97%, capillary GC), linoleic acid (≥ 99%), linolenic acid (≥ 99%), and γ-linolenic acid (≥ 99%), and methanol (99.9%, HPLC grade) were purchased from Sigma-Aldrich (St. Louis, MO). 100% 18.2 MΩ water was obtained from a Milli-Q water purification system (Millipore, Billerica, MA). 100% Cotton spool thread was purchased from a local store (JoAnn Fabrics, Columbus, OH) and Kimble 51 expansion borosilicate glass melting point capillaries (O.D. 1.5 mm) were purchased from Kimble Chase (Rockwood, TN). Human serum samples were purchased from Innovative Research (Novi, MI).