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410 result(s) for "Tryptamines - analysis"
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Murexide-derived in vitro electrochemical sensor for the simultaneous determination of neurochemicals
This work highlights the protocol employed for the simultaneous electroanalysis of tryptamine, serotonin and dopamine using a conducting poly-murexide-based electrode. To date, this is the first-of-its-kind report of simultaneous electrochemical determination of these three targets. Features of the developed electrode were identified by employing FE-SEM analysis. Under optimized conditions, the analytes underwent an irreversible electro-oxidation at the modified electrode surface, with a linear range of 0.5–40 μΜ, 0.4–40.4 μΜ and 0.5–40 μΜ for dopamine, serotonin and tryptamine, respectively. The electrolytic medium employed for the sensing was a phosphate-buffered solution with pH 7. The specificity of the developed electrode was also satisfactory in the presence of other biomolecules including L-phenylalanine, L-serine, glucose and ascorbic acid. Thus, the developed murexide-derived conducting-polymer-based electrode was used for the simultaneous sensing of the neurochemicals dopamine, serotonin and tryptamine. Electroanalysis was also demonstrated for these targets in human serum.
Self-assembled dipeptide confined in covalent organic polymers for fluorescence sensing of tryptamine in fermented meat products
Diphenylalanine(FF)-Zn self-assembly (FS) confined in covalent organic polymers (FS@COPs) with efficient fluorescence was synthesized for fluorescence sensing of biogenic amines, which was one of the most important indicators for monitoring food freshness. FS@COPs combined excellent biodegradability of self-assembled dipeptide with chemical stability, porosity and targeted site recognition of COPs. With an optimal excitation wavelength of 360 nm and an optimal emission wavelength of 450 nm, FS@COPs could be used as fluorescence probes to rapidly visualize and highly sensitive determination of tryptamine (Try) within 15 min, and the linear range was from 40 to 900 μg L −1 with a detection limit of 63.08 μg kg −1 . Importantly, the FS@COPs showed a high fluorescence quantum yield of 11.28%, and good stability, solubility, and selectivity, which could successfully achieve the rapid, accurate and highly sensitive identification of Try. Furthermore, we revealed the mechanism of FS@COPs for fluorescence sensing of targets. The FS@COPs system was applied to the fluorescence sensing of Try in real samples and showed satisfactory accuracy of 93.02%-105.25%.
Effect of collagen casing on the quality characteristics of fermented sausage
Fermented sausage is popular all over the world for its rich nutrition and unique flavor. Sausage casing is one of the key factors affecting the quality of fermented sausage. However, there is little information involved in this field. In this study, collagen casings were used as a wrapping material, and natural casings (pig casings) were used as a control. The effects of the two types of casings on biogenic amine content and other quality characteristics of fermented sausage were analyzed with increasing the storage time. The results showed that with storage time increasing, the hardness and gumminess of fermented sausage in collagen casing (CC) group were higher than those in pig casing (PC) group (P<0.05), while the elasticity in CC group was lower than that in PC group (P<0.05). In the processing and storage period, there was no significant difference in the type and content of flavor substances between the two groups. More importantly, the contents of tryptamine, putrescine, cadaverine, histamine, tyramine and phenyethylamine in fermented sausage of CC group were lower than those in PC group (P<0.05). In conclusion, this study revealed that CC could improve the quality characteristics of fermented sausage and reduce the content of biogenic amines in fermented sausage, which provides a theoretical basis for the choice of casings in industrial production in the future.
Advanced Electrochemical Sensors for Rapid and Sensitive Monitoring of Tryptophan and Tryptamine in Clinical Diagnostics
Tryptophan (Trp) and tryptamine (Tryp), critical biomarkers in mood regulation, immune function, and metabolic homeostasis, are increasingly recognized for their roles in both oral and systemic pathologies, including neurodegenerative disorders, cancers, and inflammatory conditions. Their rapid, sensitive detection in biofluids such as saliva—a non-invasive, real-time diagnostic medium—offers transformative potential for early disease identification and personalized health monitoring. This review synthesizes advancements in electrochemical sensor technologies tailored for Trp and Tryp quantification, emphasizing their clinical relevance in diagnosing conditions like oral squamous cell carcinoma (OSCC), Alzheimer’s disease (AD), and breast cancer, where dysregulated Trp metabolism reflects immune dysfunction or tumor progression. Electrochemical platforms have overcome the limitations of conventional techniques (e.g., enzyme-linked immunosorbent assays (ELISA) and mass spectrometry) by integrating innovative nanomaterials and smart engineering strategies. Carbon-based architectures, such as graphene (Gr) and carbon nanotubes (CNTs) functionalized with metal nanoparticles (Ni and Co) or nitrogen dopants, amplify electron transfer kinetics and catalytic activity, achieving sub-nanomolar detection limits. Synergies between doping and advanced functionalization—via aptamers (Apt), molecularly imprinted polymers (MIPs), or metal-oxide hybrids—impart exceptional selectivity, enabling the precise discrimination of Trp and Tryp in complex matrices like saliva. Mechanistically, redox reactions at the indole ring are optimized through tailored electrode interfaces, which enhance reaction kinetics and stability over repeated cycles. Translational strides include 3D-printed microfluidics and wearable sensors for continuous intraoral health surveillance, demonstrating clinical utility in detecting elevated Trp levels in OSCC and breast cancer. These platforms align with point-of-care (POC) needs through rapid response times, minimal fouling, and compatibility with scalable fabrication. However, challenges persist in standardizing saliva collection, mitigating matrix interference, and validating biomarkers across diverse populations. Emerging solutions, such as AI-driven analytics and antifouling coatings, coupled with interdisciplinary efforts to refine device integration and manufacturing, are critical to bridging these gaps. By harmonizing material innovation with clinical insights, electrochemical sensors promise to revolutionize precision medicine, offering cost-effective, real-time diagnostics for both localized oral pathologies and systemic diseases. As the field advances, addressing stability and scalability barriers will unlock the full potential of these technologies, transforming them into indispensable tools for early intervention and tailored therapeutic monitoring in global healthcare.
Hair analysis for detection of triptans occasionally used or overused by migraine patients—a pilot study
Purpose The aim of this study is to evaluate the detection rate of almotriptan, eletriptan, frovatriptan, sumatriptan, rizatriptan, and zolmitriptan in the hair of migraineurs taking these drugs; the degree of agreement between type of self-reported triptan and triptan found in hair; if the concentrations in hair were related to the reported cumulative doses of triptans; and whether hair analysis was able to distinguish occasional use from the overuse of these drugs. Methods Out of 300 headache patients consecutively enrolled, we included 147 migraine patients who reported to have taken at least one dose of one triptan in the previous 3 months; 51 % of the patients overused triptans. A detailed pharmacological history and a sample of hair were collected for each patient. Hair samples were analyzed by liquid chromatography-electrospray tandem mass spectrometry (LC-MS/MS) by a method that we developed. Results All the triptans could be detected in the hair of the patients. The agreement between type of self-reported triptan and type of triptan found in hair was from fair to good for frovatriptan and zolmitriptan and excellent for almotriptan, eletriptan, sumatriptan, and rizatriptan ( P  < 0.01, Cohen’s kappa). The correlation between the reported quantities of triptan and hair concentrations was statistically significant for almotriptan, eletriptan, rizatriptan, and sumatriptan ( P  < 0.01, Spearman’s rank correlation coefficient). The accuracy of hair analysis in distinguishing occasionally users from overusers was high for almotriptan (ROC AUC = 0.9092), eletriptan (ROC AUC = 0.8721), rizatriptan (ROC AUC = 0.9724), and sumatriptan (ROC AUC = 0.9583). Conclusions Hair analysis can be a valuable system to discriminate occasional use from triptan overuse.
Straightforward single-calibrant quantification of seized designer drugs by liquid chromatography–chemiluminescence nitrogen detection
Sixty-one different psychoactive substances were quantified by liquid chromatography–chemiluminescence nitrogen detection (LC–CLND) in 177 samples, using a single secondary standard (caffeine), in a trial concerning the quantitative purity assessment of drug-related material seized by the police in 2011–2012 and customs in 2011–2013 in Finland. The substances found were predominantly substituted phenethylamines, cathinones, tryptamines and synthetic cannabinoids, which were identified by appropriate methods prior to submitting the samples for quantification by LC–CLND. The equimolarity and expanded uncertainty of measurement by LC–CLND were on average 95% and 13%, respectively, based on 16 different substances. The median (mean) purity of stimulant/hallucinogenic drug samples seized at the border was 92.9% (87.6%) and in the street 82.0% (64.5%). The corresponding figures for powdery synthetic cannabinoid samples seized at the border and in the street were 99.0% (96.8%) and 90.0% (92.2%), respectively. There was generally only one active drug to be quantified in each sample. Seized herbal samples contained 0.15–9.2% of between one and three components. LC–CLND was found to be suitable for quantification of the nitrogen-containing drugs encountered in the study, showing sufficient N-equimolarity for both stimulant/hallucinogenic drugs and synthetic cannabinoids. The technique possesses great potential as a standard technique in forensic laboratories.
Metabolic changes of salicylic acid-elicited Catharanthus roseus cell suspension cultures monitored by NMR-based metabolomics
The effect of salicylic acid (SA) on the metabolic profile of Catharanthus roseus suspension cells throughout a time course (0, 6, 12, 24, 48 and 72 h after treatment) was investigated using NMR spectroscopy and multivariate data analysis. When compared to control cell lines, SA-treated cells showed a high level of sugars (glucose and sucrose) up to 48 h after treatment, followed by a dynamic change in amino acids, phenylpropanoids, and tryptamine. Additionally, one compound—2,5-dihydroxybenzoic-5-O-glucoside—was detected solely in SA-treated cells.
A rapid analytical strategy for the determination of ayahuasca alkaloids in non-ritualistic approaches by UHPLC-MS/MS
•Detection of ayahuasca alkaloids by UHPLC-MS/MS.•A simple, rapid and useful workflow to estimate the concentration of psychoactive compounds in seized materials.•Analysis of four seized samples presented concentrations of DMT ranging between 31.5 and 46.5mg/g.•Presence of β-carbolines was not detected in the products. Ayahuasca is a beverage composed by a mixture of herbs which contain the compound N,N-dimethyltriptamine (DMT) and the β-carbolines. Although its use is legalized in Brazil only for religious and spiritual ceremonies, there is a growing black market specialized in the distribution of these compounds in form of herbal material through internet and mail. The purpose of this work was the development of an ultra-high-performance liquid chromatography-tandem mass spectrometry method for the determination of ayahuasca alkaloids and its application in seized ayahuasca products. An aliquot of seized products was weighted and diluted with methanol. An aliquot of this solution was added with internal standard (DMT-d6), followed by injection in the analytical system. The limit of quantitation was 10ng/mL for DMT and 25ng/mL for harmine, harmaline and tetrahydroharmine. The concentration ranges used were 10–100ng/mL for DMT, harmine and harmaline and all analytes presented a coefficient of determination (r2)≥0,99. Analysis of four seized samples presented concentrations of DMT ranging between 31.5 and 46.5mg/g. Presence of β-carbolines was not detected in the products. The variability of DMT concentrations can be correlated with the potential intoxications described in the literature. This work successfully established a determination method for ayahuasca alkaloids in herbal material. In addition, the workflow proved to be simple, rapid and useful to estimate the concentration of psychoactive compounds in seized materials, leading to further investigation of ayahuasca ritualistic or recreational exposure.
Evaluation of the unregulated online kratom market in two east-central European countries: test purchase and analysis of potential toxicological consequences
Background As interest in human enhancement continues to rise in Europe, kratom ( Mitragyna speciosa ) products have raised significant public health concerns. Kratom, which is used for its dose-dependent stimulant and sedative effects, has grown in popularity to enhance mood and self-manage pain or opioid withdrawal symptoms. This study aimed to assess the East-Central European online kratom market, evaluate product quality, and analyze potential toxicological risks to inform evidence-based harm reduction strategies. Methods A comprehensive approach was employed, including online market surveillance, detailed content analysis of vendor websites, test purchase of products, followed by chemical analysis. Google search engine results were used to identify vendors shipping to Hungary. A total of 59 web shops were identified, and 25 distributors were selected for further analysis. Eight online sellers were included in test purchases. Mitragynine content was analyzed using supercritical fluid chromatography coupled with tandem mass spectrometry (SFC-MS/MS) and high-performance liquid chromatography with diode-array detection (HPLC-DAD). Toxicovigilance data were extracted from the United States Food and Drug Administration Adverse Event Reporting System (FAERS) and the Center for Food Safety and Applied Nutrition Adverse Event Reporting System (CAERS). Results The online kratom market in East-Central Europe is extensive and accessible, with many sellers identified in Hungary, the Czech Republic, Slovakia, and the Netherlands. While 68% (n/ N  = 17/25) of the evaluated web shops promoted enhancement effects, only 32% (n/ N  = 8/25) presented any information on potential adverse effects. Analysis of the products revealed highly variable mitragynine content, with mean concentrations ranging between 14.16 and 18.41 mg/g in powder form, and 42.60–210.20 µg/mL in prepared teas. Vigilance databases revealed 1090 cases in FAERS and 630 in CAERS associated with kratom use, with high rates of serious outcomes, including 592 deaths reported in FAERS. Conclusions The online kratom market in East-Central Europe poses a significant public health threat, particularly to individuals seeking its enhancement effects. The significant variability in the mitragynine content, combined with the lack of safety information creates a high-risk environment. Toxicological data revealed a high incidence of serious adverse reactions, particularly in cases of polysubstance use. These findings highlight the urgent need for regulatory oversight and harm reduction strategies.
Suspected Adulteration of Commercial Kratom Products with 7-Hydroxymitragynine
Introduction Kratom ( Mitragyna speciosa ), a plant native to Southeast Asia, has been used for centuries for its stimulant and opium-like effects. Mitragynine and 7-hydroxymitragynine, exclusive to M. speciosa , are the alkaloids primary responsible for Kratom's biologic and psychoactive profile, and likely contribute to its problematic use. We purchased several commercially available Kratom analogs for analysis and through our results, present evidence of probable adulteration with the highly potent and addictive plant alkaloid, 7-hydroxymitragynine. Methods A simple and sensitive LC-MS/MS method was developed for simultaneous quantification of mitragynine and 7-hydroxymitragynine in methanol extract of marketed Kratom supplements. Results We found multiple commercial Kratom products to have concentrations of 7-hydroxymitragynine that are substantially higher than those found in raw M. speciosa leaves. Conclusions We have found multiple packaged commercial Kratom products likely to contain artificially elevated concentrations of 7-hydroxymitragynine, the alkaloid responsible for M. speciosa's concerning mechanistic and side effect profile. This study describes a unique form of product adulteration, which stresses the importance of increased dietary supplement oversight of Kratom-containing supplements.