BACKGROUND: Since late 2019, fortification of \'regular\' cannabis plant material with synthetic cannabinoid receptor agonists (SCRAs) has become a notable phenomenon on the drug market. As many SCRAs pose a higher health risk than genuine cannabis, recognizing SCRA-adulterated cannabis is important from a harm reduction perspective. However, this is not always an easy task as adulterated cannabis may only be distinguished from genuine cannabis by dedicated, often expensive and time-consuming analytical techniques. In addition, the dynamic nature of the SCRA market renders identification of fortified samples a challenging task. Therefore, we established and applied an in vitro cannabinoid receptor 1 (CB1) activity-based procedure to screen plant material for the presence of SCRAs.
METHODS: The assay principle relies on the functional complementation of a split-nanoluciferase following recruitment of β-arrestin 2 to activated CB1. A straightforward sample preparation, encompassing methanolic extraction and dilution, was optimized for plant matrices, including cannabis, spiked with 5 µg/mg of the SCRA CP55,940.
RESULTS: The bioassay successfully detected all samples of a set (n = 24) of analytically confirmed authentic Spice products, additionally providing relevant information on the \'strength\' of a preparation and whether different samples may have originated from separate batches or possibly the same production batch. Finally, the methodology was applied to assess the occurrence of SCRA adulteration in a large set (n = 252) of herbal materials collected at an international dance festival. This did not reveal any positives, i.e. there were no samples that yielded a relevant CB1 activation.
CONCLUSIONS: In summary, we established SCRA screening of herbal materials as a new application for the activity-based CB1 bioassay. The simplicity of the sample preparation, the rapid results and the universal character of the bioassay render it an effective and future-proof tool for evaluating herbal materials for the presence of SCRAs, which is relevant in the context of harm reduction.

N-nitrosodimethylamine (NDMA) and N-nitrosodiethylamine (NDEA), group 2A carcinogens, were detected in finished drug products, including metformin, ranitidine, sartans and other drugs which caused multiple recalls in the USA and Europe. Important studies also reported the formation of NDMA when ranitidine and nitrite were added to simulated gastric fluid. Our objective was to screen finished drug products from Europe and USA for nitrosamine impurities and investigate the formation of NDMA in metformin finished drug products when added to simulated gastric fluid. One dosage unit of 30 different commercially available drugs, including metformin, sartans, and ranitidine were tested for NDMA, NDEA, and dimethylformamide (DMF) impurities, using a liquid chromatography-mass spectrometry (LC-MS) method. Then, 6 metformin finished drug products were tested in stomach conditions for 2 h at 37 °C in a 100 mL solution with a pH of 2.5 and different nitrite concentrations (40, 10, 1, 0.1 mM) and tested for NDMA, and DMF using LC-MS. We measured NDMA, NDEA, and DMF in 30 finished drug products. NDMA and DMF were quantified for metformin drug products in simulated gastric fluid with different nitrite concentrations. None of the 30 drugs showed concerning levels of NDMA, NDEA, or DMF when tested as single tablets. However, when metformin tablets are added to simulated gastric fluid solutions with high nitrite concentrations (40 mM and 10 mM), NDMA can reach amounts of thousands of nanograms per tablet. At the closest concentration to physiologic conditions we used, 1 mM, NDMA is still present in the hundreds of nanograms in some metformin products. In this in vitro study, nitrite concentration had a very important effect on NDMA quantification in metformin tablets added to simulated gastric fluid. 1 mM nitrite caused an increase above the acceptable daily intake set by the U.S. Food and Drug Administration (FDA) for some of the metformin drugs. 10 mM, 40 mM nitrite solutions generated NDMA amounts exceeding by more than a hundred times the acceptable daily intake set by the FDA of 96 nanograms. These findings suggest that metformin can react with nitrite in gastric-like conditions and generate NDMA. Thus, patients taking metformin could be exposed to NDMA when high nitrite levels are present in their stomach, and we recommend including a statement within the Patient Package Inserts/Instructions for use.

Herbal medicines are widely used for clinical purposes worldwide. These herbs are susceptible to phytopathogenic fungal invasion during the culturing, harvesting, storage, and processing stages. The threat of fungal and mycotoxin contamination requires the evaluation of the health risks associated with these herbal medicines. In this study, we collected 138 samples of 23 commonly used herbs from 20 regions in China, from which we isolated a total of 200 phytopathogenic fungi. Through morphological observation and ITS sequencing, 173 fungal isolates were identified and classified into 24 genera, of which the predominant genera were Fusarium (27.74%) and Alternaria (20.81%), followed by Epicoccum (11.56%), Nigrospora (7.51%), and Trichocladium (6.84%). Quantitative analysis of the abundance of both Fusarium and Alternaria in herbal medicines via RT-qPCR revealed that the most abundant fungi were found on the herb Taraxacum mongolicum, reaching 300,000 copies/μL for Fusarium and 700 copies/μL for Alternaria. The in vitro mycotoxin productivities of the isolated Fusarium and Alternaria strains were evaluated by using liquid chromatography-tandem mass spectrometry (LC-MS/MS), and it was found that the Fusarium species mainly produced the acetyl forms of deoxynivalenol, while Alternaria species mainly produced altertoxins. These findings revealed widely distributed fungal contamination in herbal medicines and thus raise concerns for the sake of the quality and safety of herbal medicines.

The Burkholderia cepacia complex (Bcc) is the number one bacterial complex associated with contaminated Finished Pharmaceutical Products (FPPs). This has resulted in multiple healthcare related infection morbidity and mortality events in conjunction with significant FPP recalls globally. Current microbiological quality control of FPPs before release for distribution depends on lengthy, laborious, non-specific, traditional culture-dependent methods which lack sensitivity. Here, we present the development of a culture-independent Bcc Nucleic Acid Diagnostic (NAD) method for detecting Bcc contaminants associated with Over-The-Counter aqueous FPPs. The culture-independent Bcc NAD method was validated to be specific for detecting Bcc at different contamination levels from spiked aqueous FPPs. The accuracy in Bcc quantitative measurements was achieved by the high degree of Bcc recovery from aqueous FPPs. The low variation observed between several repeated Bcc quantitative measurements further demonstrated the precision of Bcc quantification in FPPs. The robustness of the culture-independent Bcc NAD method was determined when its accuracy and precision were not significantly affected during testing of numerous aqueous FPP types with different ingredient matrices, antimicrobial preservative components and routes of administration. The culture-independent Bcc NAD method showed an ability to detect Bcc in spiked aqueous FPPs at a concentration of 20 Bcc CFU/mL. The rapid (≤ 4 hours from sample in to result out), robust, culture-independent Bcc NAD method presented provides rigorous test specificity, accuracy, precision, and sensitivity. This method, validated with equivalence to ISO standard ISO/TS 12869:2019, can be a valuable diagnostic tool in supporting microbiological quality control procedures to aid the pharmaceutical industry in preventing Bcc contamination of aqueous FPPs for consumer safety.

Ibandronate sodium, a third-generation diphosphate drug used worldwide to treat osteoporosis, has the advantages of convenient use, low toxicity, and significant therapeutic effects. However, the residual organic solvents in the synthesis process of sodium ibandronate not only have a negative impact on the efficacy of the drug, but also lead to a decrease in drug stability. Moreover, if the residual amounts of these solvents exceed safety standards, they may pose serious threats to human health. This study successfully established a convenient and efficient method based on headspace-gas chromatography (HS-GC) for the simultaneous determination of five residual solvents (methanol, acetone, benzene, toluene, 1-pentanol) in the raw materials of ibandronate sodium. The results indicated that satisfactory analytical performance can be achieved by using DB-624 capillary column (30 m×0.32 mm×1.8 μm) and a flame ionization detector in conjunction with headspace autosampling and a temperature program. The specific operating conditions included an initial temperature of 40 ℃, with a hold of 2 min, followed by a temperature ramp first to 200 ℃ at a rate of 5 ℃/min and then to 240 ℃ at a rate of 20 ℃/min, with a hold of 5 min. Nitrogen with a flow rate of 1 mL/min and split ratio of 14∶1 was used as the carrier gas. The headspace vial temperature was maintained at 80 ℃, and the sample equilibration time was 20 min. Under the established analytical conditions, good linear relationships were obtained between the mass concentrations of methanol (72-216 μg/mL), acetone (120-360 μg/mL), benzene (0.048-0.144 μg/mL), toluene (21.36-64.08 μg/mL), and 1-pentanol (120-360 μg/mL) and their corresponding peak areas, with correlation coefficients (r) greater than 0.990. The limits of detection for these solvents were 2.88, 0.011, 0.90, 0.24, and 0.024 ng/mL, respectively, with limits of quantification of 11.5, 0.043, 3.6, 0.96, and 0.096 ng/mL, respectively. Furthermore, the recoveries of these solvents ranged from 86.3% to 101.9%, with relative standard deviations (RSDs, n=3) of less than 2.49%. The proposed method is simple, accurate, reliable, and suitable for the rapid and simultaneous determination of five residual solvents in the raw materials of ibandronate sodium. This study has important practical significance in improving drug safety and ensuring public health.

Amphotericin B (AmB) is a polyene-macrolide antimicrobial drug with a broad antibacterial spectrum and remarkable efficacy against deep fungal infections. It binds to ergosterol on the fungal cell membrane and alters its permeability, thereby destroying the membrane. AmB is a multicomponent antimicrobial medication that contains a wide range of impurities, rendering quality analysis extremely difficult. In the current Chinese Pharmacopoeia (Edition 2020) and European Pharmacopoeia (EP10.3), high performance liquid chromatography (HPLC) is applied to examine related substances in AmB. However, this technique presents a number of issues. For instance, the mobile phases used in the HPLC method described in both references contain nonvolatile inorganic salts, which cannot be coupled with a mass spectrometry (MS) detector. In addition, because the mobile phases used have a low pH, the component/impurities of AmB drug can easily be degraded or interconverted during the analytical process, leading to reduced analytical accuracy. Therefore, the accuracy and sensitivity of this method must be improved. In this study, a method based on on-line two-dimensional high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (2D HPLC-Q TOF/MS) was developed to analyze the impurity profile of AmB in accordance with the Chinese Pharmacopoeia (Edition 2020) and European Pharmacopoeia (EP10.3). The method combines on-line dilution and a multiple-capture HPLC system to achieve the efficient separation of AmB component/impurities. It also resolves the issue of poor solvent compatibility in 2D HPLC, increases the analytical flux, enhances the automation capability, reduces the mutual conversion of AmB and its impurities during the analytical process, and increases the detection sensitivity of the method. MS was also used to determine the structural inference of unstable components and impurities. An XBridge Shield C18 column (250 mm×4.6 mm, 3 μm) was used for first-dimensional-liquid chromatography with gradient elution using methanol-acetonitrile-4.2 g/L citric acid monohydrate solution (10∶30∶60, v/v/v, pH 4.7) as mobile phase A and methanol-acetonitrile-4.2 g/L citric acid monohydrate solution (12∶68∶20, v/v/v, pH 3.9) as mobile phase B. An Xtimate C8 column (10 mm×2.1 mm, 5 μm) was used as the trap column, and trapping and desalting were performed using 10 mmol/L ammonium formate aqueous solution containing 0.1% formic acid-acetonitrile (95∶5, v/v). An Xtimate C8 column (250 mm×2.1 mm, 5 μm) was used for second-dimensional-liquid chromatography with gradient elution using 10 mmol/L ammonium formate aqueous solution containing 0.1% formic acid-acetonitrile (95∶5, v/v) and 10 mmol/L ammonium formate aqueous solution containing 0.1% formic acid-acetonitrile (5∶95, v/v) as mobile phases. The data were collected in positive-ion mode. In this study, the structures of six impurities in amphotericin B were inferred, according to the fragmentation, the MS and MS2 spectra of each impurity. The developed method can be used to quickly and sensitively analyze the impurity profile of AmB. Furthermore, the research results on impurity profiles can be applied to guide improvements in AmB production.

The present study investigates the chemical composition variances among Pinelliae Rhizoma, a widely used Chinese herbal medicine, and its common adulterants including Typhonium flagelliforme, Arisaema erubescens, and Pinellia pedatisecta. Utilizing the non-targeted metabolomics technique of employing UHPLC-Q-Orbitrap HRMS, this research aims to comprehensively delineate the metabolic profiles of Pinelliae Rhizoma and its adulterants. Multivariate statistical methods including PCA and OPLS-DA are employed for the identification of differential metabolites. Volcano plot analysis is utilized to discern upregulated and downregulated compounds. KEGG pathway analysis is conducted to elucidate the differences in metabolic pathways associated with these compounds, and significant pathway enrichment analysis is performed. A total of 769 compounds are identified through metabolomics analysis, with alkaloids being predominant, followed by lipids and lipid molecules. Significant differential metabolites were screened out based on VIP > 1 and p-value < 0.05 criteria, followed by KEGG enrichment analysis of these differential metabolites. Differential metabolites between Pinelliae Rhizoma and Typhonium flagelliforme, as well as between Pinelliae Rhizoma and Pinellia pedatisecta, are significantly enriched in the biosynthesis of amino acids and protein digestion and absorption pathways. Differential metabolites between Pinelliae Rhizoma and Arisaema erubescens are mainly enriched in tyrosine metabolism and phenylalanine metabolism pathways. These findings aim to provide valuable data support and theoretical references for further research on the pharmacological substances, resource development and utilization, and quality control of Pinelliae Rhizoma.

Recently, benchtop nuclear magnetic resonance (NMR) spectrometers utilizing permanent magnets have emerged as versatile tools with applications across various fields, including food and pharmaceuticals. Their efficacy is further enhanced when coupled with chemometric methods. This study presents an innovative approach to leveraging a compact benchtop NMR spectrometer coupled with chemometrics for screening honey-based food supplements adulterated with active pharmaceutical ingredients. Initially, fifty samples seized by French customs were analyzed using a 60 MHz benchtop spectrometer. The investigation unveiled the presence of tadalafil in 37 samples, sildenafil in 5 samples, and a combination of flibanserin with tadalafil in 1 sample. After conducting comprehensive qualitative and quantitative characterization of the samples, we propose a chemometric workflow to provide an efficient screening of honey samples using the NMR dataset. This pipeline, utilizing partial least squares discriminant analysis (PLS-DA) models, enables the classification of samples as either adulterated or non-adulterated, as well as the identification of the presence of tadalafil or sildenafil. Additionally, PLS regression models are employed to predict the quantitative content of these adulterants. Through blind analysis, this workflow allows for the detection and quantification of adulterants in these honey supplements.

Coronavirus disease of 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an ongoing outbreak, disrupting human life worldwide. Vaccine development was prioritized to obtain a biological substance for combating the viral pathogen and lessening disease severity. In vaccine production, biological origin and relevant materials must be carefully examined for potential contaminants in conformity with good manufacturing practice. Due to fast mutation, several SARS-CoV-2 variants and sublineages have been identified. Currently, most of COVID-19 vaccines are developed based on the protein sequence of the Wuhan wild type strain. New vaccines specific for emerging SARS-CoV-2 strains are continuously needed to tackle the incessant evolution of the virus. Therefore, in vaccine development and production, a reliable method to identify the nature of subunit vaccines is required to avoid cross-contamination. In this study, liquid chromatography-mass spectrometry using quadrupole-time of flight along with tryptic digestion was developed for distinguishing protein materials derived from different SARS-CoV-2 strains. After analyzing the recombinantly produced receptor-binding domain (RBD) of the SARS-CoV-2 spike protein, nine characteristic peptides were identified with acceptable limits of detection. They can be used together to distinguish 14 SARS-CoV-2 strains, except Kappa and Epsilon. Plant-produced RBD-Fc protein derived from Omicron strains can be easily distinguished from the others with 4-5 unique peptides. Eventually, a peptide key was developed based on the nine peptides, offering a prompt and precise flowchart to facilitate SARS-CoV-2 strain identification in COVID-19 vaccine manufacturing.

In Asia, some herbal preparations have been found to be adulterated with undeclared synthetic medicines to increase their therapeutic efficiency. Many of these adulterants were found to be toxic when overdosed and have been documented to bring about severe, even life-threatening acute poisoning events. The objective of this study is to develop a rapid and sensitive ambient ionization mass spectrometric platform to characterize the undeclared toxic adulterated ingredients in herbal preparations. Several common adulterants were spiked into different herbal preparations and human sera to simulate the clinical conditions of acute poisoning. They were then sampled with a metallic probe and analyzed by the thermal desorption-electrospray ionization mass spectrometry. The experimental parameters including sensitivity, specificity, accuracy, and turnaround time were prudently optimized in this study. Since tedious and time-consuming pretreatment of the sample is unnecessary, the toxic adulterants could be characterized within 60 s. The results can help emergency physicians to make clinical judgments and prescribe appropriate antidotes or supportive treatment in a time-sensitive manner.