Application of Central Composite Design for the Optimization of Reverse-Phase HPLC/DAD Separation of the cis- and trans- Isomers of Long-Chain Unsaturated Fatty Acids

Quantitative Polyunsaturated Fatty Acid Analysis of Chia Seed Oil by High-Performance Liquid Chromatography

Alpha-linolenic acid (ALA) and linoleic acid (LA), abundant in chia seed oil, are useful polyunsaturated fatty acids (PUFA) with numerous health benefits. The objectives of the present study were to explore the optimum extraction condition of chia seed oil and the possibilities of direct analysis of ALA and LA in chia seed oil by reversed-phase high-performance liquid chromatography with ultraviolet detection (RP-HPLC-UV). The optimized chia seed oil extraction condition was set by the usage of Soxhlet extrator with hexane as a solvent, with the solvent to solid ratio of 8 and the extraction time of 8 h. Prior to HPLC-UV analysis, the oil was saponified in order to get the free fatty acids for detection. The results showed that the proposed HPLC-UV method allowed the quantification of ALA and LA in chia seed oil. The method was simple, rapid (within 18 min) and sensitive (limit of detection 0.006 mg/mL for ALA and 0.02 mg/mL for LA) and precise (RSD ≤ 2%). Thus, the proposed experimental designs were shown to offer considerable advantages over traditional derivatization approaches in the ALA and LA analyses.

Fabrication of paper-based analytical devices optimized by central composite design

In this work, an application of a design of experiments approach for the optimization of an isoniazid assay on a single-area inkjet-printed paper-based analytical device (PAD) is described.