Quantitation of Fat Soluble Vitamins in Different Walnut Genotypes and Commercial Cultivars; a Comprehensive and Robust LC-MS/MS Method Validation

Öz

Walnut, being both nutritious and delicious, has been regarded as a health food due to its preventive and therapeutic effects. In the present study, a robust LC-MS/MS analytical method was developed to simultaneously quantify five fat soluble vitamins (D₂, D₃, K₂, E, K₁) in eleven walnut genotypes and two commercial cultivars. Linearity, accuracy, inter- and intra-day precision, detection limit (LOD), quantification limit (LOQ) and uncertainty (U at confidence level of 95% (k = 2)) were the validation parameters of the developed LC-MS/MS method. The established linearity ranges for the studied vitamins were between 50 and 1200 mg L⁻¹ for vitamins D₂, D₃, K₁, between 100-2400 mgL⁻¹ for vitamin E and between 200-4800 mg L⁻¹ for vitamin K₂. The coefficients of determination for the vitamins D₂, D₃, K₂, E, K₁ were between 0.9990, 0.9991, 0.9995, 0.9997, 0.9991, respectively. Vitamins D₃, K₂ and K₁ were not present in the analysed walnut samples. On the other hand, vitamins E and D₂ were in high quantities in all studied walnut samples. D₂ and E were the most abundant fat soluble vitamins in MDE32 (29.1 mg g^-1 dry plant) and MDE5 (15.2 mg g^-1 dry plant) genotypes. Despite the fact that the walnut was selected as real life sample, the validated LC-MS/MS method is enforceable to a broad range of food species.

Anahtar Kelimeler

• Fat soluble vitamins,analytical method validation,LC-MS/MS,walnut

Kaynakça

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