A Simple Quantitative Approach for the Determination of Long and Medium Chain Lipids in Bio-relevant Matrices by High Performance Liquid Chromatography with Refractive Index Detection

Abstract

Abstract. There is increasing attention in the literature towards understanding the behaviour of lipidbased drug formulations under digestion conditions using in vitro and in vivo methods. This necessitates a convenient method for quantitation of lipids and lipid digestion products. In this study, a simple and accessible method for the separation and quantitative determination of typical formulation and digested lipids using high performance liquid chromatography coupled to refractive index detection (HPLC-RI) is described. Long and medium chain lipids were separated and quantified in a biological matrix (gastrointestinal content) without derivatisation using HPLC-RI on C 18 and C 8 columns, respectively. The intraand inter-assay accuracy was between 92% and 106%, and the assays were precise to within a coefficient of variation of less than 10% over the range of 0.1-2 mg/mL for both long and medium chain lipids. This method is also shown to be suitable for quantifying the lipolysis products collected from the gastrointestinal tract in the course of in vivo lipid digestion studies.

Esterification of Glycerol With Oleic Acid Over Hydrophobic Zirconia-Silica Acid Catalyst and Commercial Acid Catalyst: Optimization and Influence of Catalyst Acidity

“…The OA and GMO groups of the sample were separated using a mobile phase consisted of ACN/water (80:20 v/v) with 0.1% TFA (v/v of total mobile phase). Meanwhile, GDO and GTO groups were separated using ACN/MeOH/THF (40:40:20 v/v/v) (Lee et al, 2013). The injection volume was 10 μL and the diluted samples were eluted at a 220 μL/min flow rate.…”

Development of a Novel Hydrophobic ZrO2–SiO2 Based Acid Catalyst for Catalytic Esterification of Glycerol with Oleic Acid

“…Isocratic method was used in separation and quantitative determination. The OA and GMO groups of the sample were separated using a mobile phase consisting of ACN/water (80:20 v/v) with 0.1% TFA (v/v of total mobile phase); GDO and GTO groups were separated using ACN/MeOH/THF (40:40:20 30 The injection volume was 10 μL, and the diluted samples were eluted at a 220 μL/min flow rate. The column and RI detector temperatures were set at 40°C.…”

Immobilised Lipase for In Vitro Lipolysis Experiments

“…However, these have shortcomings such as long run times, labour‐intensive, high‐cost, requirement of specialised equipment and use of volatile solvents. Reversed‐phase HPLC using refractive index detection has recently been shown to be a useful tool to determine lipid composition following in vivo digestion that it is simple and nondestructive . Thus, this method was employed to separate and quantify FA analytically during digestion for correlation with total FA produced as indicated by the pH stat titration.…”

“…Reversed-phase HPLC using refractive index detection has recently been shown to be a useful tool to determine lipid composition following in vivo digestion that it is simple and nondestructive. 20 Thus, this method was employed to separate and quantify FA analytically during digestion for correlation with total FA produced as indicated by the pH stat titration. Samples (200 :L) were taken during digestion for analysis of FA content by HPLC.…”