A Simple, Sensitive, and Label-Free Platform for the Quantification of Lactoferrin in Camel and Goat Milk Based on Thin-Layer Chromatography

Abstract

Lactoferrin is a multifunctional glycoprotein secreted in most body fluids, especially in milk. It has been identified in many mammalian species, such as human, goat, cow, and camel. Lactoferrin exerts a significant protective biological role by acting as an antimicrobial, antiviral, immunomodulatory, and anti-inflammatory agent. This work describes a simple, sensitive, direct, inexpensive, and label-free method for quantifying lactoferrin in camel and goat milk based on thin-layer chromatography (TLC). Analysis and quantification of lactoferrin were done through simple protein extraction procedure followed by subjecting the obtained extract to TLC using RP-18 TLC silica gel plates and a ternary mobile phase composed of 2-propanol: TFA: water (40:5:55, v:v:v). Densitometric detection was carried out at 250 nm. The proposed method showed linear calibration curves over the range of 10.0–205.0 µg/mL. The limit of detection and limit of quantitation were found to be 3.50 and 10.0 µg/mL, respectively. The method was fully validated according to the ICH guidelines. The average lactoferrin concentrations in camel and goat milk were determined as 29.70 ± 0.69 and 38.12 ± 0.53 μg/mL, respectively. The reliability of the assay was demonstrated through direct comparison with a previously reported high-performance liquid chromatography (HPLC) method for lactoferrin analysis. The presented study represents the first report for the application of TLC in quantifying lactoferrin in natural extracts.