Nano-liquid chromatography and electromigration techniques applied to the analysis of dietary supplements. A review

Dietary supplements (DSs) or food supplements (FSs) are products widely consumed to support the diet. They could contain amino acids, peptides, proteins, vitamins, minerals, herbs, and compounds of botanical origin. Since they are considered food, they are not subjected to approval by government agencies. Therefore, they are popular because they can be bought without a prescription and are easily available on the internet. The addition of drugs to DSs/FSs is not allowed because it could cause serious damage to health. Therefore, there is a need for analytical methods capable of performing qualitative/quantitative analysis of the declared content and to verify the presence of adulterants. Among the analytical techniques employed, miniaturized techniques have been successfully applied to the analysis of such products. In this review, applications performed with capillary electrophoresis and nano-/capillary-liquid chromatography, and microchip electrophoresis published in the period 2018–2025 (July), are reported and discussed.