In this study, dietary exposures to 9 food emulsifiers, including 4 polysorbates and 5 esters of fatty acids, were assessed in Korean population. For the exposure assessment, three scenarios of the consumption, including mean and P95 in whole population and mean in consumed population, were applied. As a result, the EDIs of 9 emulsifiers were overall low compared to the ADIs.
View Article and Find Full Text PDFLattice oxygen redox offers an unexplored way to access superior electrochemical properties of transition metal oxides (TMOs) for rechargeable batteries. However, the reaction is often accompanied by unfavourable structural transformations and persistent electrochemical degradation, thereby precluding the practical application of this strategy. Here we explore the close interplay between the local structural change and oxygen electrochemistry during short- and long-term battery operation for layered TMOs.
View Article and Find Full Text PDFDespite the high energy density of lithium-rich layered-oxide electrodes, their real-world implementation in batteries is hindered by the substantial voltage decay on cycling. This voltage decay is widely accepted to mainly originate from progressive structural rearrangements involving irreversible transition-metal migration. As prevention of this spontaneous cation migration has proven difficult, a paradigm shift toward management of its reversibility is needed.
View Article and Find Full Text PDFCalcium-ion batteries (CIBs) are considered to be promising next-generation energy storage systems because of the natural abundance of calcium and the multivalent calcium ions with low redox potential close to that of lithium. However, the practical realization of high-energy and high-power CIBs is elusive owing to the lack of suitable electrodes and the sluggish diffusion of calcium ions in most intercalation hosts. Herein, it is demonstrated that calcium-ion intercalation can be remarkably fast and reversible in natural graphite, constituting the first step toward the realization of high-power calcium electrodes.
View Article and Find Full Text PDFThe worldwide spread of illegal sexual enhancement products is posing a threat to public health. The aim of this study was to investigate illegal products claiming to be effective in improving sexual performance through the online or offline markets between 2014 and 2017; these products include foods, dietary supplements, counterfeit drugs, and herbal medicines. These samples were analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the presence of 80 PDE-5 inhibitors (PDE-5i) and analogues.
View Article and Find Full Text PDFIllicit psychoactive substances have threatened public health worldwide. An active metabolite of ADB-CHMINACA and MDMB-CHMINACA was identified for the first time in a powder-type product found in an airmail package. The structure of compound 1 was elucidated by a combination of gas chromatography-mass spectrometry (GC-MS), liquid chromatography-high resolution mass spectrometry (LC-HRMS), infrared (IR) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy.
View Article and Find Full Text PDFA sensitive and specific high-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry (LC-QTOF-MS) method combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed for the determination of grayanotoxins I and III in dietary supplements and homemade wine. Grayanotoxins I and III were successfully extracted using solid-phase extraction cartridges, characterized by LC-QTOF-MS, and quantitated by LC-MS/MS. The LC-MS/MS calibration curves were linear over concentrations of 10-100 ng/mL (grayanotoxin I) and 20-400 ng/mL (grayanotoxin III).
View Article and Find Full Text PDFSynthetic hair-growth compounds have been illegally used in diverse products to enhance the short-term efficacy of these products. In this study, a rapid and simultaneous method for the determination of hair-growth compounds in adulterated products based on ultra high pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was developed and validated. The limit of detection (LOD) and limit of quantitation (LOQs) of the method were 0.
View Article and Find Full Text PDFFood Addit Contam Part A Chem Anal Control Expo Risk Assess
February 2018
In this study, we developed a UPLC-PDA and LC-Q-TOF/MS method to identify and measure the following prohibited substances that may be found in dietary supplements:triaminodil, minoxidil, bimatoprost, alimemazine, diphenylcyclopropenone, α-tradiol, finasteride, methyltestosterone, spironolatone, flutamide, cyproterone, dutasteride, and testosterone 17-propionate.The method was validated according to International Conference on Harmonization guidelines in terms of specificity, linearity, accuracy, precision, LOD, LOQ, recovery, and stability. The method was completely validated showing satisfactory data for all method validation parameters.
View Article and Find Full Text PDFFood Addit Contam Part A Chem Anal Control Expo Risk Assess
January 2018
A new minoxidil analogue was detected in an illegal dietary supplement advertised as a hair-growth treatment. The analogue was identified using ultra-performance liquid chromatography (UPLC), high-resolution mass spectrometry (LC-HR-MS) and nuclear magnetic resonance (NMR) spectroscopy. The compound was structurally elucidated as a minoxidil analogue in which the piperidinyl group of minoxidil was replaced with a pyrrolidinyl group corresponding to a molecular formula of CHNO.
View Article and Find Full Text PDFFood Addit Contam Part A Chem Anal Control Expo Risk Assess
March 2018
The purpose of this study was to validate a rapid, simple and accurate method using ultra-performance liquid chromatography (UPLC) for the simultaneous determination of 26 anti-diabetic compounds in illegally adulterated dietary supplements. The method was validated for specificity, linearity, limit of detection, limit of quantitation, precision, accuracy, recovery and stability. All compounds were separated with a resolution of over 1.
View Article and Find Full Text PDFOver the past decades, mass spectrometry technologies have been developed to obtain mass accuracies of one ppm or less. Of the newly developed technologies, quadrupole time-of-flight mass spectrometry (Q-TOF-MS) has emerged as being well suited to routine and high-throughput analyses of pharmaceuticals. Dietary supplements and functional foods have frequently been found to be contaminated with pharmaceuticals.
View Article and Find Full Text PDFFood Addit Contam Part A Chem Anal Control Expo Risk Assess
February 2017
A new tadalafil analogue was found in a commercial dietary supplement for enhancing sexual performance. The compound was detected by a high-performance liquid chromatography-diode array detector (HPLC-DAD). The analogue was isolated using semi-preparative HPLC, and its accurate mass was established by two LC-high-resolution-mass spectrometers (LC-HRMS).
View Article and Find Full Text PDFFood Addit Contam Part A Chem Anal Control Expo Risk Assess
November 2016
A novel, stable, simple and specific ultra-performance liquid chromatography method with ultraviolet detection (205 nm) for the simultaneous analysis of 25 anti-hypertensive substances was developed. The method was validated according to the International Conference of Harmonisation guidelines with respect to linearity, accuracy, precision, limit of detection (LOD), limit of quantitation (LOQ) and stability. From the ultra-performance liquid chromatography results, we identified the LOD and LOQ of solid samples to be 0.
View Article and Find Full Text PDFA sensitive and specific LC/MS/MS method was developed for the simultaneous analysis of 35 compounds used for treating hypertension as adulterants in dietary supplements. The method was validated for specificity, linearity, accuracy, precision, limit of detection, limit of quantitation, stability and recovery. The limit of detection and limit of quantitation ranged from 0.
View Article and Find Full Text PDFThe primary purpose of this study was to develop and validate a method based on UPLC with UV and UPLC-MS-MS for the simultaneous analysis of different cannabinoids and synthetic cannabinoids in food as well as in herbal and dietary supplements. The limits of detection and quantitation of the method ranged from 0.1 to 0.
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June 2016
A new tadalafil analogue was found, along with nortadalafil, using HPLC-DAD during the inspection of a health product sold without official approval. The analogue was separated using a semi-preparative HPLC system and its structure was determined by a combination of mass spectrometry and NMR spectroscopy. The compound was identified as a tadalafil analogue in which the N-methyl group of tadalafil was replaced with a tadalafil precursor moiety.
View Article and Find Full Text PDFFood Addit Contam Part A Chem Anal Control Expo Risk Assess
March 2016
The purpose of this study was to develop a method to analyse the concentration of multiple illegal narcotics present in dietary supplements. To this end, we established and optimised a procedure using LC-MS/MS simultaneously to analyse 28 narcotic compounds in various forms of dietary supplements, including powders, tablets, liquids and capsules. In addition, candy and cookies that have also had detected cases of adulteration were also analysed.
View Article and Find Full Text PDFFood Addit Contam Part A Chem Anal Control Expo Risk Assess
October 2014
Sulfites in foods were analysed using four methods: optimised Monier-Williams (official method), modified Rankine, HPLC and ion-exchange chromatography (IEC). The modified Rankine and HPLC methods were performed according to the previously reported methods but with some modifications. The IEC method was carried out through a combination of a modified Rankine apparatus and an anion-exchange column for the first time.
View Article and Find Full Text PDFA study was performed to evaluate the estimated daily intakes (EDI) of benzoates for the average and high (90th percentile) consumers by age and sex categories in Korea. The estimation of daily intakes of benzoates was based on individual dietary intake data from the National Health and Nutrition Survey in 1998 and on the determination of benzoates in eight food categories. The EDI of benzoates for average consumers of different age groups ranged from 0.
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