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1.
Forensic Sci Int ; 325: 110884, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34245937

ABSTRACT

New psychoactive substances are being launched in the drug market at a rapidly growing pace. More than 950 new psychoactive substances have been reported to the United Nations Office on Drugs and Crime. The development of new psychoactive substance abuse has drawn risks on public health and safety. Phenethylamines, along with other stimulants, accounted for the majority of the new psychoactive substances being reported in the past decade. This study presents a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous screening of 74 conventional and artificial phenethylamines in urine samples. The chromatographic analysis was performed by a direct dilute-and-shoot procedure using a Phenomenex Kinetex® Phenyl-Hexyl column (10 cm × 2.1 mm i.d., 1.7 µm) and two mobile phases (A: 0.1% formic acid aqueous solution with 5 mM ammonium acetate, B: 0.1% formic acid methanolic solution). The mass fragments were collected under the multiple reaction monitoring mode. The linearity range located in 1.0-50.0 ng/mL for quantitative analysis. The limit of detection and lower limit of quantification for 74 phenethylamines were 0.5 ng/mL and 1.0 ng/mL, respectively. The method was validated and further applied to analyze authentic urine samples. Twenty samples were tested positive of seven phenethylamines from 67 samples, whereas the contents detected were 9.8 ng/mL to 147.1 µg/mL with dilution factors of 40 to 20,000 folds.


Subject(s)
Illicit Drugs/urine , Phenethylamines/urine , Psychotropic Drugs/urine , Chromatography, Liquid , Humans , Reproducibility of Results , Substance Abuse Detection , Tandem Mass Spectrometry
2.
Forensic Sci Int ; 315: 110429, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32784041

ABSTRACT

Synthetic cathinones, which are a group of ß-keto analogs of phenethylamine, have been reported as the most emerging new psychoactive substances in the past decade. The quantity and variety of synthetic cathinones have continued to increase, which poses considerable risks to public health and social security. In this study, an analytical method based on liquid chromatography-tandem mass spectrometry (LCMS/MS) was established for the simultaneous determination of 73 synthetic cathinones and related metabolites in urine. The chromatographic analysis was performed using a Kinetex® Biphenyl column (10 cm ×2.1 mm, 1.7 µm), applying a gradient mobile phase, comprising 0.1 % formic acid aqueous solution with 5 mM ammonium acetate and 0.1 % formic acid methanolic solution; the entire run time of the analysis was within 8 min. The multiple reaction monitoring (MRM) mode was employed to collect the monitoring and quantitative ion pairs. Intra-day/inter-day precision and accuracy were less than 10 % for all the studied analytes. The limits of detection and quantification for all the analytes were 0.1-0.5 ng/mL and 0.5-1.0 ng/mL, respectively. The matrix effect was satisfactory for all the analytes, with a deviation lower than 20 %. The present method was further applied to 67 authentic urine samples in which 13 different synthetic cathinones were detected from 32 positive samples. The abuse of poly-synthetic cathinones was examined that up to seven items was detected in one case from authentic samples in this study.


Subject(s)
Alkaloids/urine , Chromatography, Liquid/methods , Tandem Mass Spectrometry/methods , Humans , Psychotropic Drugs/urine , Substance Abuse Detection/methods
3.
J Food Drug Anal ; 28(2): 292-301, 2020 Jun 15.
Article in English | MEDLINE | ID: mdl-35696119

ABSTRACT

An incident of sartan medicine contamination was notified by Europe in June 2018. The contaminant was identified as a probable carcinogenic nitrosamine and the recalls of sartan medicines were soon made. Since then, more nitrosamine contaminants in sartan medicines were reported. To broaden the applicability and variety in nitrosamine determination, a multi-analyte method is required. In this study, a feasible and sensitive multi-analyte LC-MS/MS method for determination of 12 nitrosamines in sartans was established, where the active pharmaceutical ingredients and final products merchandised in Taiwan were also examined. Chromatographic separation was achieved on an Xselect® HSS T3 column (15 cm × 3 mm i.d., 3.5 µm) with gradient elution using mobile phase A consisting of 0.1% formic acid in water and mobile phase B consisting of 0.1% formic acid in acetonitrile/methanol (2:8). Validation of the proposed method was also carried out. The limit of detection and limit of quantification for 12 nitrosamines were 20 ng/g and 50 ng/g, respectively. The intra-day and inter-day recoveries of nitrosamines were among 80-120% with precision of 20% for most nitrosamines within sartans matrices. The method was successfully established and applied to authentic samples which a total of 98 positive samples containing 5 distinct nitrosamines, including N-nitrosodiethylamine, N-nitrosodimethylamine, N-nitroso-N-methyl-4-aminobutyric acid, N-nitrosomorpholine and N-nitrosopiperidine, were detected from 557 authentic samples.

4.
Vaccine ; 37(49): 7203-7206, 2019 11 20.
Article in English | MEDLINE | ID: mdl-31648910

ABSTRACT

HPV vaccines are highly immunogenic. A two-dose schedule for 9-14 year-old is recommended. However, no data exist regarding the impact of age, menarche status and body mass index (BMI) on the immune response to a two-dose schedule. In this post-hoc analysis, we present antibody titers to HPV6/11/16/18 in 9-13 year-old girls participating in a randomized clinical trial and assigned to receive two doses of quadrivalent HPV vaccine at 6 months interval (NCT00501137). Antibody titers were measured at month 7 and 24 of the study by using a competitive Luminex immunoassay (cLIA).Both, at Month 7 and 24 the GMTs for four HPV genotypes were similar across the age bands, and did not vary significantly by menarche status. Overweight and obese girls had lower GMTs. More than 99% of girls remained seropositive for HPV 6/11/16 and 89% for HPV18 at month 24. Comprehensive data in overweight and obese vaccines are warranted.


Subject(s)
Antibodies, Viral/blood , Antibody Formation/physiology , Human Papillomavirus Recombinant Vaccine Quadrivalent, Types 6, 11, 16, 18/immunology , Menarche/immunology , Papillomavirus Infections/prevention & control , Adolescent , Body Mass Index , Child , Female , Humans , Immunization Schedule
5.
Clin Trials ; 8(6): 699-704, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21900340

ABSTRACT

BACKGROUND: In contrast to the gradual pace of conventional vaccine trials, evaluation of influenza vaccines often must be accelerated for use in a pandemic or for annual re-licensure. Descriptions of how best to design studies for rapid completion are few. PURPOSE: In August, 2010, we conducted a rapid trial with a seasonal influenza vaccine for 2010-2011 given to persons vaccinated with an adjuvanted H1N1 vaccine in 2009, to determine whether re-exposure to the H1N1(2009) component of the seasonal vaccine would cause increased reactions. We describe the strategies that we believe were responsible for success in meeting the desired timeline. METHODS: The key means for expediting the study were: use of a few experienced, well-staffed centers; efficient completion of administrative approvals; advance recruitment of volunteers; synchronized start among centers with rapid completion (≤1 week) of first visits; rapid data assembly via the Internet; and a well-prepared data analysis plan. We chose to use a randomized, blinded, cross-over design to allow estimation of vaccine-attributable adverse event rates, with sufficient power (320 participants) to detect events occurring at true rates ≥1% with ≥90% probability. RESULTS: Planned enrollment numbers, center synchronization, and timelines, including review by a safety board prior to the cross-over step (second doses), were achieved. A detailed safety report was delivered to federal health officials just 32 days after study initiation and was used to fine-tune public messaging prior to the mass vaccination programs across Canada. LIMITATIONS: This aggressive timeline could not have been met without opportunities for careful planning and the prior existence of a network of experienced, collaborating trial centers. CONCLUSIONS: The means used to accelerate this study timeline were successful and could be used in other urgent situations but the mechanics of collaborative trials must be well rehearsed as a precondition.


Subject(s)
Clinical Trials as Topic/methods , Influenza A Virus, H1N1 Subtype/drug effects , Influenza Vaccines , Influenza, Human/prevention & control , Adult , Canada , Humans , Information Management , Middle Aged , Patient Selection , Personnel Selection , Research Design , Time Factors , Young Adult
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