A lipid soluble form of Vitamin E, gamma-Tocopherol is important to human health as an antioxidant and food additive. Vitamin E deficiency, often the result of poor nutrition or low absorption of dietary fat, is monitored in patient serum samples by LC-MS/MS or HPLC. This Certified Spiking Solution® is suitable for use as a starting material in the preparation of linearity standards, calibrators, and controls in a variety of testing applications from diagnostic testing of Vitamin E deficiency by LC-MS/MS or HPLC to quality control testing of tocopherol-based dietary supplements or pharmaceutical preparations.