Detection of adulteration of anti-hypertension dietary supplements and traditional Chinese medicines with synthetic drugs using LC/MS

Assessment of Undeclared Synthetic Drugs in Dietary Supplements in an Analytical View: A Comprehensive Review

Dietary supplements have gained widespread attention globally as they are supposed to be healthier than synthetic pharmaceutical compounds with fewer side effects. Unlike common prescription drugs, dietary supplements are readily available to the general public. However, over the past few years, all kinds of legal and illegal drugs, have been detected in dietary supplements without labeling to defraud consumers, resulting in serious public health consequences. Due to the increasing number of drug frauds in dietary supplements, their consumption will undoubtedly risk consumers. Therefore; the importance of high-tech analytical methods in their assessment for controlling food quality seems undeniable. The current review examines the analytical techniques that focus on adulterating health products with undeclared pharmaceuticals, including registered and banned drugs. The present study referred to a survey from 2004 to 2021 based on articles in the Scopus database.

A new approach to ion exchange chromatography with conductivity detection for adulterants investigation in dietary supplements

The extent of adulteration of dietary supplements has significantly increased in recent years. This situation worries health authorities and requires auxiliary analytical tools for the investigation of illegal substances purposely added. Ion exchange chromatography with conductivity detection is a consolidated analytical technique for the determination of inorganic compounds in various matrices. This technique has been applied to the pharmaceutical characterization of mainly impurities and degradation products. This work presents a new approach to ion exchange chromatography as a screening method to investigate the presence of amfepramone, femproporex, sibutramine, bisacodyl and amiloride in dietary supplements advertised for weight loss. The method was optimized and validated using a Metrosep C4 100/4.0 cation exchange column. The mobile phase consisted of 1.8 mm HNO₃ containing 2% acetonitrile (v/v), with a flow rate of 0.9 ml min^-1 , and nonsuppressed conductivity detection was applied. The limits of detection and quantification varied from 1.01 to 3.62 mg L^-1 and from 1.48 to 8.72 mg L^-1 , respectively. The proposed method was successful applied to 78 solid dietary supplement samples, in two of which adulterations were found. Moreover, ion exchange chromatography with conductivity detection could be easily used for quality control without prior complex sample pre-treatment.

Determination of adulterants in whey protein food supplements by liquid chromatography coupled to Orbitrap high resolution mass spectrometry

Abstract Liquid chromatography coupled to Orbitrap high resolution mass spectrometry was shown to be an adequate technique to control the adulteration of whey protein food supplements with prohibited substances, not declared on the labels. An extraction method combined with an instrumental analysis that allowed for the determination of 105 substances in whey protein food supplements, was established. The pre-treatment of the samples consisted of protein precipitation and solid-phase extraction using weak cation exchange functionalized polymeric sorbent cartridges. The samples were directly analyzed by LC-Orbitrap-HRMS. The selectivity, limit of detection, repeatability, recovery, carryover and matrix effect were estimated as the validation parameters. The repeatability obtained was 96.19% and the recovery 83.80%, but carryover and the matrix effect were not observed. The present method was successfully applied to the analysis of commercial samples, verifying adulteration by diuretics (conivaptan and politiazide) and a stimulant (benfluorex) in seven of the eleven brands evaluated.

Formation of a Hydroxymethylfurfural-Cysteine Adduct and Its Absorption and Cytotoxicity in Caco-2 Cells

Adducts of 5-hydroxymethylfurfural (HMF)-amino acids are formed during food processing and digestion; the elimination capacity of in vitro intestinal digests of biscuits, instant noodles, and potato crisps for HMF is 652, 727, and 540 μg/g, respectively. However, the safety of these adducts is unknown. In this study, an HMF-cysteine adduct named 1-dicysteinethioacetal-5-hydroxymehtylfurfural (DCH), which was found to be produced in the gastrointestinal tract after HMF intake, was prepared to test its effect toward Caco-2 cells. Compared with HMF, the adduct displayed lower cytotoxicity against Caco-2 cells with an IC₅₀ value of 31.26 mM versus 14.95 mM (HMF). The DCH did not induce cell apoptosis, whereas HMF significantly increased the apoptosis rate after incubation at concentrations of 16, 32, and 48 mM for 72 h. DCH showed an absorption rate considerably lower than that of HMF by Caco-2 cells. Lower absorption of DCH may result in lower toxicity compared with HMF against Caco-2 cells. Intracellular transformation of DCH has been observed.

Mass spectrometric analysis of pharmaceutical adulterants in products labeled as botanical dietary supplements or herbal remedies: a review

The increased availability and use of botanical dietary supplements and herbal remedies among consumers has been accompanied by an increased frequency of adulteration of these products with synthetic pharmaceuticals. Unscrupulous producers may add drugs and analogues of various classes, such as phosphodiesterase type 5 (PDE-5) inhibitors, weight loss, hypoglycemic, antihypertensive and anti-inflammatory agents, or anabolic steroids, to develop or intensify biological effects of dietary supplements or herbal remedies. The presence of such adulterated products in the marketplace is a worldwide problem and their consumption poses health risks to consumers. Analytical methods that allow rapid and reliable testing of dietary supplements for the presence of synthetic drugs are needed to address such fraudulent practices. Mass spectrometry (MS) and hyphenated techniques such as liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) have become primary tools in this endeavor. The present review critically assesses the role and summarizes the applications of MS in the analysis of pharmaceutical adulterants in botanical dietary supplements and herbal remedies. The uses of MS techniques in detection, confirmation, and quantification of known pharmaceutical adulterants as well as in screening for and structure elucidation of unexpected adulterants and novel designer drugs are discussed.