Simultaneous determination of 11 nootropic substances potentially adulterated in dietary supplements for improving brain function using ultra-performance liquid chromatography and liquid chromatography-quadrupole-time-of-flight mass spectrometry.

Recently, the demand for improved brain function and concentration has increased in the dietary supplement market. However, to artificially enhance their pharmacological efficacy, dietary supplements may be illegally adulterated with unauthorised substances. Therefore, we developed a rapid and accurate method to simultaneously determine 11 nootropic substances using an ultra-high-performance liquid chromatography (UPLC) system equipped with a photodiode array (PDA) detector. In addition, sample preparation procedures were semi-optimised for various types of matrices, including solid (hard capsule, tablet, powder, and pill) and liquid (oil and extract) samples. The method was validated to determine the limit of detection (LOD), limit of quantification (LOQ), method detection limit (MDL), method quantitation limit (MQL), specificity, linearity, precision, accuracy, recovery, stability, and matrix effects. The validation results satisfied international validation guideline requirements. To test the applicability of the method, 55 real samples advertised as effective brain health, memory, and cognition supplements were analysed. Among the real samples, vinpocetine (2.483 and 7.296 µg/g), and kavain (69-44.056 µg/g) were detected. In addition, the detected compounds were confirmed by comparing their fragmentation patterns with those of the reference standards using liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-QTOF/MS). In conclusion, the UPLC-PDA method not only rapidly and accurately quantifies illegal nootropics but also enables the pre-emptive investigation and identification of 11 nootropic substances in illegal dietary supplements to protect public health.

Intercomparison study of fragmentation pathways and fragment ion structures for screening of illegal drugs and their novel analogues used to adulterate dietary supplements using liquid chromatography/quadrupole time-of-flight mass spectrometry.

RATIONALE: As public interest in health and immunity has increased in recent years, so has the demand for dietary supplements. However, supplements adulterated with illegal drugs and their novel analogues are being sold even as the pharmacological efficacies of these drugs are being advertised. Since the use of these illegal compounds can have serious side effects, they pose a risk to public health. Hence, in this study, we propose a strategy for proactively testing drugs and novel analogues that may be added to dietary supplements illegally. METHODS: The optimal conditions for liquid chromatography/quadrupole time-of-flight mass spectrometry were explored to determine the fragmentation patterns for 60 compounds. The optimal conditions were established by comparing the areas and heights of the precursor ion peaks at a fragmentor voltage of 125 or 175 V. Furthermore, the optimized spectra were acquired using collision energies of 1 to 50 eV. The energy value was selected based on the condition that the mass error of the precursor ions is 10 ppm or lower. RESULTS: The fragmentation pathway of each product ion and its chemical structure were predicted and determined. In addition, the obtained structural information was used to screen 18 seized samples. Based on the precursor ions and the corresponding fragmentation patterns, the unknown compounds present in the samples were identified as desulfonylchlorosildenafil and propoxyphenylthiohydroxy homosildenafil. CONCLUSIONS: We obtained mass spectrometry-based information for various compounds by predicting the fragmentation pathways and chemical structures of their fragment ions. Subsequently, based on the obtained structural information, we tested several seized samples and were able to detect two novel analogues in four of the samples. Therefore, the proposed approach is suitable for quickly and accurately identifying the unknown compounds detected in real-world samples.

Application of LC-MS/MS and UHPLC-Q-Orbitrap methods for determining 54 steroids in illegal dietary supplements and other sample types.

RATIONALE: With the development of the Internet and social network services, the public access to or use of illegal products has been increased via on/offline black markets. Steroids refer to the compounds yielding strong treatment effects on some diseases or muscle building, and are classified as the pharmaceutical compounds that are prohibited for personal use without a prescription. The prohibition is made for their potential risk to cause serious adverse effects along with their efficacies. METHODS: To monitor the distribution of illicit products containing steroids, a simple and reliable analytical method was established and validated, allowing rapid and simultaneous determination of 54 steroids in them. During the screening, LC-Q-Orbitrap/MS was performed first followed by quantitative analysis using LC-MS/MS. For the accurate and reliable analysis, the samples were extracted using QuEChERS to reduce the matrix effect. RESULTS: After the screening of 617 illegal samples advertised as being effective in alleviating various diseases or improving athletic performance with the established LC-Q-Orbitrap/MS method, the validated LC-MS/MS method was used to perform the quantitative analysis of the detected steroids. Of these, 142 samples were adulterated with steroids, and several samples with two or more steroids were detected. Due to the lack of previous studies on the toxicity of these illicit products, the side effects of consuming them are unpredictable and could be harmful. CONCLUSIONS: The development of LC-Q-Orbitrap/MS method accompanied by LC-MS/MS could be successfully applied to the inspection of illegal steroid products for public health, enabling the rapid and accurate detection of analytes and incorporation of non-analyte components.

Detection of 94 PDE-5is and Their Analogs Including N-Desmethylthiosildenafil in Various Formulations of Dietary Supplements and Food Samples Using HPLC and LC-Q-TOF/MS.

Consumption of foods and dietary supplements (DS) adulterated with unprescribed or non-permitted phosphodiesterase-5 inhibitors (PDE-5i) and their analogs can cause serious risk to human health. This study aims to analyze 93 PDE-5i and their analogs present in adulterated foods and DS using an established and validated method involving high-performance liquid chromatography (HPLC). The method was validated in solid and liquid samples, resulting in a limit of detection and quantitation of 0.03-0.5 and 0.08-1.6 µg/mL, respectively. Using the validated method, a total of 404 samples were screened. It was found that 32% of 404 samples were illegally adulterated with PDE-5i and their analogs; moreover, 16.9% of the adulterated samples were found to contain more than three compounds. HPLC-quadrupole-time-of-flight (TOF)/mass spectrometry (MS) analysis was conducted on all the samples to confirm the detected compounds accurately based on fragmentation ion patterns. In addition, sildenafil and tadalafil were detected from the capsule shells of DS unusually. Subsequently, the detected compounds were identified and quantified using HPLC at concentrations ranging from 0.007 to 370.0 mg/g. NMR analysis was carried out to confirm the accurate chemical structure of a compound found during the TOF/MS analysis, which did not match with the 93 reference standards.; it was identified to be N-desmethylthiosildenafil. In this study, various PDE-5i compounds and their analogs were detected from low to high concentrations in a sample. Therefore, the study sheds light on the misuse of PDE-5i and their analogs in consumable products, which pose a severe threat to public health.

Application of liquid chromatography-high resolution mass spectrometry and liquid chromatography-tandem mass spectrometry methods to 45 weight loss compounds in health functional food, food, and illegal drug.

In order to effectively and quickly monitor such illegal food and drugs, simultaneous screening and quantitative analysis for multiple compounds are needed. In this study, we established a method of identifying fragmentation ions of 45 compounds for weight loss using liquid chromatography and high-resolution mass spectrometry and developed a quantitation method through liquid chromatography and tandem mass spectrometry. Note that, 656 samples selected as health functional food, food, and illegal drug were applied. The detection rate of banned weight loss compounds in health functional food, food, and illegal drug was showed as 19.2, 27.3, 40.7%, respectively. Among them, sibutramine, sennoside A and B, ephedrine were most frequently detected in 237 samples that contained weight loss compounds. The detection range about sibutramine was 0.03-159.3 mg/g, sennoside was 0.1-97.6 mg/g, and ephedrine was 0.1-587.7 mg/g in the detected 237 samples. In addition, the unknown compounds not included in our simultaneous analysis method in some samples were identified as furosemide and chlorpheniramine. High selectivity of high resolution mass spectrometry combined with these fragmentation pathways and tandem mass spectrometry methods can be successfully applied to screening and identifying 45 weight loss compounds for continuous blocking and supervision of illegally distributed health functional food, food, and illegal drug.

Application of predicted fragmentation pathways and fragment ion structures for detecting steroids and selective androgen receptor modulators in dietary supplements using liquid chromatography-quadrupole time-of-flight mass spectrometry.

RATIONALE: Dietary supplements advertised to strengthen muscles have earned fame among athletes. However, several products containing unauthorized compounds are often detected, which can cause a public health risk. Particularly, steroids and selective androgen receptor modulators (SARMs) can cause serious side effects as hormone modulators. In this study, we analyzed 15 steroids and 20 SARMs using liquid chromatography-quadrupole time-of-flight mass spectrometry (LC/QTOFMS) to provide fundamental information about fragmentation pathways and fragment ion structures. METHODS: The optimal conditions of LC/QTOFMS were explored to obtain fragmentation patterns for each compound. The optimal conditions were established by comparing the area and height of the precursor ion peak at 125 or 175 V as a fragmentor energy. Furthermore, the optimized spectra were acquired by applying collision energy ranging from 1 to 50 eV. The energy value was selected under the condition that the mass error of precursor ions was less than 10 ppm. RESULTS: The 35 compounds were classified on the basis of their chemical core structures: arylpropionamide (3 compounds), quinolinone (2), pyrrolidinylbenzonitrile (1), indole (2), tropanol (2), phenylaxadaizole (1), hydantoin (2), phenylthiazole (1), nitrothiophene (1) and steroidal derivative (20). Fragmentation pathways and the chemical structure of each product ion were predicted and identified. Furthermore, the obtained structural information was applied to screen seized samples. As a result, 10 seized samples were confirmed to contain one or more SARMs by comparing each precursor ion and fragmentation pattern. CONCLUSIONS: The application to real samples for accurate screening indicated that the same fragmentation patterns and product ions as one or more SARM standards were detected and identified in the seized samples advertised as muscle building. Therefore, this study can contribute to ensuring the safety of public health through providing fundamental information about the risk of illegal adulteration.

Simultaneous screening of 21 potential adulterants in dietary supplements for the treatment of prostate diseases using ultra-performance liquid chromatography and liquid chromatography-electrospray ionization-tandem mass spectrometry.

Reports of the number of adulteration cases using illegal therapeutic substances in dietary supplements have increased. In recent years, various dietary supplements are being distributed that exaggerate the efficacy of treatment for prostate-related diseases. To develop the preemptive monitoring method, we selected 21 prostate-related therapeutic substances and optimized the simultaneous ultra-performance liquid chromatography and liquid chromatography-electrospray ionization-tandem mass spectrometry and pretreatment procedures for various types of matrices including solid, liquid, and soft capsule samples. The methods were validated by determining the specificity, linearity, limit of detection, limit of quantification, method detection limit, method quantitation limit, precision, accuracy, recovery, stability, and matrix effect. The simultaneous methods were validated according to the international guidelines. In addition, using the validated methods, 81 real samples, which were searched and purchased by focusing on promotional phrases, such as prostate and prostatic hyperplasia, were successfully screened. As a result, sildenafil and tadalafil were detected in one seized capsule sample (5.15 and 14.6 mg/g, respectively). Synthetically, our approach could be useful for the determination of illegal therapeutic substances potentially adulterated in various types of dietary supplements.

Screening sexual performance enhancing compounds and their analogues in counterfeit and illicit erectile dysfunction drugs by high-performance liquid chromatography and liquid chromatography-tandem mass spectrometry.

The growth of the counterfeit and illicit drugs market is attributable in part to phosphodiesterase type-5 inhibitor (PDE-5is) medications for erectile dysfunction (ED). PDE-5is and their analogues are being increasingly supplied as counterfeit and illicit drugs marketed to enhance sexual performance. Herein, we screened and confirmed a total of 181 such counterfeit and illicit drugs used to date to enhance sexual performance by high-performance liquid chromatography (HPLC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Out of 181 samples, PDE-5is and their analogues were detected in 156 samples, with 49.4% containing two or more components in a single sample. Sildenafil, tadalafil, and miscellaneous group were detected a rates of 64.1%, 34.4%, and 1.5% times and concentrations of 0.04-496 mg/g, 0.02-147 mg/g, and 0.54-16.4 mg/g, respectively with multiple compound groups also detected in single samples. Overdosing on these drugs can lead to adverse effects, the toxicities of combined administrations have not been researched, and administering multiple components in a single sample can be fatal. We recommend that counterfeit and illicit drugs for enhancing sexual performance be continuously controlled and supervised for the protection of public health, and more studies into toxicity and side effects are required.

Development and validation of liquid chromatography-tandem mass spectrometry method for screening six selective androgen receptor modulators in dietary supplements.

Selective androgen receptor modulators (SARMs) are compounds with specific androgenic properties that have been investigated for the treatment of conditions such as muscle wasting disease. The reported androgenic properties have resulted in their use by athletes, and consequently they have been on the World Anti-Doping Agency prohibited list for more than a decade. To minimise the chance of an unattended positive doping test and to avoid potential serious health problems, adequate screening methods for the detection of a wide range of SARMs in these supplements is necessary. In this study, a rapid and accurate liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated simultaneously to screen and quantify six SARMs in dietary supplements, with confirmation by liquid chromatography-quadrupole-time of flight mass spectrometry (LC-Q-TOF/MS). The validated method was applied to 60 dietary supplements obtained by on-line and direct purchase from international vendors in 2020. Various SARMs were detected at high concentrations in 20 products which were advertised as having androgenic properties. For example, andarine was present at 7.2% in one product, and GW501516 was found at 3.49% in the another product. Furthermore, MK-677 and YK-11, not disclosed on the label, were detected in some products. YK-11 is easily hydrolysed in just a few hours. Although YK-11 is particularly unstable, such that the protonated ion [M + H]+ at m/z 431 for YK-11 was not detected, mass fragmentation, and a [M+ Na]+ ion at m/z 453.3 confirmed the presence of YK-11. Additionally, hydrolysed YK-11 under acidic conditions was confirmed by NMR spectral data, and 1H NMR and 13C NMR spectral data for YK-11 were in good agreement with literature data. This rapid and accurate LC-MS/MS method can therefore be successfully applied to screen and identify SARMs for the continuous control and supervision of dietary supplements.

Application of a simultaneous screening method for the detection of new psychoactive substances in various matrix samples using liquid chromatography/electrospray ionization tandem mass spectrometry and liquid chromatography/quadrupole time-of-flight mass spectrometry.

RATIONALE: Recently, new psychoactive substances (NPS) have emerged as a public health risk. Particularly, their chemical structures are modified to avoid detection. Synthetic NPS with effects similar to those of illegal drugs have been recently detected and synthesized worldwide, including MDMB-FUBINACA and APINAC, making it essential to rapidly and accurately detect NPS. METHODS: Fourteen NPS with similar structures were selected and their structures identified using 1 H and 13 C NMR spectroscopy. Additionally, we proposed the fragmentation pattern of each compound using liquid chromatography/quadrupole time-of-flight mass spectrometry (LC/QTOF-MS). A simultaneous analytical method using liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) was also developed and applied to real samples to detect the 14 NPS. The method was validated based on the specificity, linearity, limit of detection (LOD), limit of quantification (LOQ), precision, accuracy, matrix effect, and stability according to international validation guidelines. RESULTS: The established method was used to screen 65 different matrix samples using LC/ESI-MS/MS. By comparing the calculated product ion ratios with those of standards, 2C-B in one of the real samples and 5F-MDMB-PICA in 20 samples were identified. For re-confirmation of detected compounds, the fragmentation pattern of each compound was compared with that of each standard using LC/QTOF-MS. CONCLUSIONS: In this study, LC/QTOF-MS data were used to elucidate the structures and fragmentation patterns of 14 NPS. A simultaneous method was developed using LC/ESI-MS/MS, which was applied to 65 real samples. The presented method and results can assist in ensuring the safety of public health from illegal adulteration.

Simultaneous screening of dietary supplements for 25 anti-hyperlipidemic substances using ultra-performance liquid chromatography and liquid chromatography/electrospray ionization tandem mass spectrometry.

RATIONALE: Recently, illegal dietary supplements containing unauthorized compounds have been seized and internationally publicized with a warning to avoid their consumption. This adulteration can be a serious threat to public health because of insufficient and reliable safety data as well as their undesirable side effects. It is, therefore, essential to rapidly and accurately develop and simultaneously validate analytical methods for these unauthorized anti-hyperlipidemic substances. METHODS: Dietary supplements were screened simultaneously for 25 anti-hyperlipidemic drugs using an ultra-high-performance liquid chromatography (UPLC) system with a photodiode array (PDA) detector and LC/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS). The method validation, according to ICH guidelines, considered specificity, linearity, limit of detection (LOD), limit of quantification (LOQ), precision, accuracy, matrix effects, and stability for solid and liquid blank samples. The established UPLC-PDA and LC/ESI-MS/MS methods were applied to screen 103 dietary supplements for 25 anti-hyperlipidemic substances. RESULTS: Using the validated methods, the screened samples were found to contain peaks with similar retention times and PDA spectra. By comparing the calculated precursor-product ion ratios with those of standards, lovastatin and lovastatin acid were detected at concentrations from LOQ to 4.12 mg/g and LOQ to 9.65 mg/g, respectively. CONCLUSIONS: The developed UPLC-PDA and LC/ESI-MS/MS analytical methods were applied to 103 real samples, of which 13 samples were found to contain lovastatin and lovastatin acid. In view of the increasing demand for dietary supplements in the treatment of hyperlipidemic diseases, widespread use of these methods will contribute to consumer health by ensuring the safety of dietary supplements.

Simultaneous separation and determination of 20 potential adulterant antigout and antiosteoporosis pharmaceutical compounds in herbal food products using LC with electrospray ionization MS/MS and LC with quadrupole-time-of-flight MS.

An analytical method for the simultaneous and reliable determination of 20 antigout and antiosteoporosis pharmaceutical compounds in adulterated health food products was developed using liquid chromatography with electrospray ionization tandem mass spectrometry and liquid chromatography with quadrupole-time-of-flight mass spectrometry. The method was validated through the determination of specificity, linearity, limit of detection, and limit of quantification, method detection limit, method quantitation limit, precision, accuracy, recovery, and stability. The matrix effect was also determined. The validation results of the developed method are as follows: for solid and liquid blank samples, limits of detection ranged from 0.05 to 5.00 ng/mL and limits of quantification ranged from 0.15 to 15.00 ng/mL. Linearity was acceptable, and the correlation coefficients (R2 ) were ≥0.99 for all target compounds. Both intra and interday precision were less than 9.16% RSD, and accuracies ranged from 95.31 to 116.68%. Mean recoveries for different types of dietary supplements classified as powders, liquids, tablets, and capsules were found to be 80.81 to 117.62% with less than 15.00% relative standard deviation. The stability of the standard mixture solution was less than 11.72% relative standard deviation after 48 h. By the proposed method, the presence of dexamethasone was determined in seized herbal food products at concentrations that ranged from 126 to 215 µg/g.

Development of a specific fragmentation pattern-based quadrupole-Orbitrap™ mass spectrometry method to screen drugs in illicit products.

Over the past decade, illicit drugs have been founded in marketed products, which pose a risk to public health. In particular, newly designed analogues synthesized by chemical modification of parent compounds to avoid detection by authorities are frequently detected worldwide. Although many analytical methods for determination of drugs have been reported, analytical methods using high-resolution mass spectrometry, which has the advantage of rapid screening and accurate identification of new substances, are necessary to control illicit drugs in marketed products. In this study, a rapid analytical method using an Orbitrap™ mass spectrometer for identification of illicit drugs in marketed products was developed. The 32 drugs were classified as benzodiazepine-, synthetic cannabinoid-, amphetamine- and benzylpiperazine-type drugs according to their chemical structures, and from their fragmentation patterns in tandem mass spectrometry spectra of an established method. The method validation gave a limit of detection of 0.06-5.30 ng/mL and a limit of quantification of 0.18-16.50 ng/mL, high linearity (R2 > 0.994) and mean recoveries of spiked matrix-blank samples ranging from 83.7% to 117.1%. Approximately 71% of 21 samples collected over 3 years were found to individually contain one of four types of benzodiazepines or two different synthetic cannabinoids. In one case, levels as high as 827.2 mg/g were measured suggesting adulteration at high levels, which suggests that potential illicit products containing drugs should be regularly screened to protect public health.

Simultaneous determination of illegal drug substances in dietary supplements for gout and osteoporosis using ultra-performance liquid chromatography and liquid chromatography-quadrupole-time-of-flight mass spectrometry.

The aim of this study was to simultaneously determine the presence of unauthorized drug substances in health foods and herbal products used in the treatment of conditions such as gout and anti-osteoporosis. Therefore, we developed and optimised a rapid and accurate method to simultaneously measure 20 anti-gout and anti-osteoporosis drug substances using an ultra-high-performance liquid chromatography (UPLC) system equipped with a photodiode array (PDA) detector. The method was validated to fully meet internationally accepted standards. LODs and LOQs spiked in solid and liquid negative samples were ranged from 0.12 to 1.50 µg/mL, and ranged from 0.36 to 4.50 µg/mL. Linearities (R2> 0.999), stabilities (RSD ≤ 2.92%), accuracies (84.25∼106.62%, intra-day; 84.56∼105.85%, inter-day), precisions (RSD ≤ 3.71% on the intra-day; RSD ≤ 3.47% on the inter-day), recoveries spiked in various type of blank samples such as powder, liquid, tablet, and capsule were determined within 81.20-116.20 %, respectively. From a confirmation of matrix effects (88.06∼110.50% in solid blank; 89.16∼110.52% in liquid blank), it was confirmed that this method was not significantly affected by a sample matrix. The validated method was used to analyse 116 samples containing health foods, herbal products, and seized forensic samples advertised to be effective anti-gout and anti-osteoporosis agents. Of the 20 drug substances screened, dexamethasone was detected and confirmed by comparing the tandem mass spectrometry (MS/MS) fragment ion patterns of a reference standard and the sample using LC-quadrupole-time-of-flight (Q-TOF)/MS. The concentrations of adulterants in seized forensic samples ranged from 0.013 to 0.022 %.

Application of screening methods for weight-loss compounds and identification of new impurities in counterfeit drugs.

With the increasing prevalence of obesity, the use of counterfeit drugs for weight loss is widespread owing to their easy and rapid availability. Since counterfeit weight-loss drugs are not prepared under the rigorous standard of Good Manufacturing Practice (GMP), they pose a risk to public health and cause significant side effects. To counteract the risk posed by counterfeit drugs, we investigated counterfeit weight-loss drugs seized by the Incheon Customs Services using UHPLC-PDA. Five of 23 confiscated samples with distinctive pink-coloured coating contained levothyroxine, sennoside A and B, and phenolphthalein in amounts ranging from 0.03-132.40 mg/g. In addition, three unknown compounds in one of the adulterated samples containing phenolphthalein were structurally elucidated by several analytical techniques. Their accurate masses corresponded to molecular formula of C34H22O7, C34H20O6, and C20H12O3, respectively. These compounds were identified as impurities, possibly produced during the synthesis of phenolphthalein or by improper removal during purification. These impurities were detected for the first time in counterfeit drugs.

Screening of illegal sexual enhancement supplements and counterfeit drugs sold in the online and offline markets between 2014 and 2017.

The 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. The developed method was validated as follows: LODs and LOQs spiked in solid- and liquid-type negative samples (0.03-3.33 ng/mL and 0.08-10.00 ng/mL), linearities (R2 > 0.997), recoveries spiked negative samples (82.2-109.3 %), accuracies (81.6-118.9 %), precisions (≥ 6.5%, RSD) of intra-day and inter-day, and stability (≥10.0%, RSD). Out of 362 measured samples, 145 were adulterated samples mostly detected in food (51%). Sildenafil group (50%) was frequently observed, followed by tadalafil group (41%). Although sildenafil and tadalafil were mainly detected in adulterated samples, their analogues were also found. In particular, new analogues have appeared steadily on illicit erectile dysfunction (ED) products even after they were first discovered. The concentration of detected samples ranged from 0.1 to 826.0 mg/g, and sildenafil of them contained a considerable amount in illicit ED products in 2014, posing a potential toxicology risk of public health. The testing method is fast and reliable making it suitable for both routine screening and up-to-date quantitative analysis of PDE-5i and their analogues in suspicious foods, dietary supplements, and counterfeit drugs.

Isolation and structural identification of a novel minoxidil analogue in an illegal dietary supplement: triaminodil.

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 C8H13N5O. The new analogue has been named triaminodil. As this is the first report of the compound, there are no chemical, toxicology or pharmacological data available.

Determination of 26 anti-diabetic compounds in dietary supplements using a validated UPLC method.

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 1.5. The limits of detection and quantitation were 0.10-1.70 and 0.30-5.10 µg g-1 in a solid sample, respectively; the corresponding values were 0.10-1.25 and 0.30-3.75 µg ml-1 in a liquid sample. The correlation coefficient was > 0.99, precisions were 0.11-3.30% (intra-day) and 0.05-6.15% (inter-day), and accuracies were 83-108% (intra-day) and 85-109% (inter-day). The recoveries were measured with six dosage forms, and the results were acceptable as 87-117% with relative standard deviations ≤ 6.44%. The relative standard deviations of stability were ≤ 3.40% and the standard solution was stable for 48 h. Ninety-six samples were obtained from on/off-line markets and were analysed using the developed method. Among these samples, pioglitazone and glibenclamide were found in seven samples and the concentrations of each compound were 0.15% and 0.26-0.51%, respectively. With the increasing adulteration of dietary supplements with anti-diabetic drugs, this method may be helpful to protect public health and safety.

Determination of illegal adulteration of dietary supplements with synthetic hair-growth compounds by UPLC and LC-Q-TOF/MS.

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. The linearity was good (R2 > 0.999) with intra- and inter-day precision values of 0.2-3.4% and 0.3-2.9%, respectively. Moreover, the intra- and inter-day accuracies were 87-102% and 86-103%, respectively, and the precision was better than 9.4% (relative standard deviation).Hence, the proposed method is precise and has high quality,and can be utilised to comprehensively and continually monitor illegal drug adulteration in various forms of dietary supplements. Furthermore, to evaluate the applicability of the proposed method, we analysed 13 hair-growth compounds in 78 samples including food and dietary supplements. Minoxidil and triaminodil were detected in capsules at concentrations of 4.69 mg/g and 6.54 mg/g. In addition, finasteride was detected in a tablet at 13.45 mg/g. In addition, the major characteristic fragment ions were confirmed once again using LC-Q-TOF/MS for higher accuracy.

Simultaneous analysis by Quadrupole-Orbitrap mass spectrometry and UHPLC-MS/MS for the determination of sedative-hypnotics and sleep inducers in adulterated products.

Adulterated products are continuously detected in society and cause problems. In this study, we developed and validated a method for determining synthetic sedative-hypnotics and sleep inducers, including barbital, benzodiazepam, zolpidem, and first-generation antihistamines, in adulterated products using Quadrupole-Orbitrap mass spectrometry and ultrahigh performance liquid chromatography with tandem mass spectrometry. In Quadrupole-Orbitrap mass spectrometry analysis, target compounds were confirmed using a combination of retention time, mass tolerance, mass accuracy, and fragment ions. For quantification, several validation parameters were employed using ultrahigh performance liquid chromatography with tandem mass spectrometry. The limit of detection and limit of quantitation was 0.05-53 and 0.17-177 ng/mL, respectively. The correlation coefficient for linearity was more than 0.995. The intra- and interassay accuracies were 86-110 and 84-111%, respectively. Their precision values were evaluated as within 4.0 (intraday) and 10.7% (interday). Mean recoveries of target compounds in adulterated products ranged from 85 to 116%. The relative standard deviation of stability was less than 10.7% at 4°C for 48 h. The 144 adulterated products obtained over 3 years (2014-2016) from online and in-person vendors were tested using established methods. After rapidly screening with Quadrupole-Orbitrap mass spectrometry, the detected samples were quantified using ultrahigh performance liquid chromatography with tandem mass spectrometry. Two of them were adulterated with phenobarbital.