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1.
Forensic Toxicol ; 42(1): 31-44, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37755669

RESUMO

PURPOSE: According to recent reports, cannabigerol (CBG) concentration level in blood and body fluids may have forensic utility as a highly specific albeit insensitive biomarker of recent cannabis smoking. While the analytical sensitivity of cannabidiol (CBD), Δ9-tetrahydrocannabinol (Δ9-THC), cannabichromene (CBC) or cannabinol (CBN) estimation by gas chromatography-mass spectrometry (GC-MS) is similar and sufficiently high, it is exceptionally low in the case of CBG (ca. 25 times lower than for the other mentioned cannabinoids). The purpose of this study is to explain the reasons for the extremely low analytical sensitivity of GC-MS in estimating CBG and to present possible ways of its improvement. METHODS: Nuclear magnetic resonance (NMR) data and GC-MS responses to CBG and its various derivatization and transformation products were studied. RESULTS: The validation data of individual derivatives of CBG and its transformation products were established. CBG silylation/acylation or hydration allows to decrease LOD about 3 times, whereas the formation of pyranic CBG derivative leads to 10-times decrease of LOD. The paper enriches the literature of the subject by providing MS and NMR spectra, not published so far, for derivatives of CBG and its transformation products. The most likely cause of low GC-MS response to CBG is also presented. CONCLUSIONS: The presented results shows that although the signal increase of CBG can be obtained through its derivatization by silylation and/or acylation, the greatest increase is observed in the case of its cyclization to the pyranic CBG form during the sample preparation process. The CBG cyclization procedure is very simple and workable in estimating this cannabinoid in blood/plasma samples.


Assuntos
Canabidiol , Canabinoides , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Cromatografia Gasosa-Espectrometria de Massas , Canabidiol/análise , Canabinol/análise
2.
Menopause ; 30(6): 629-634, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37130371

RESUMO

OBJECTIVE: Pelvic organ prolapse (POP) occurs predominantly in postmenopausal women. Restoration of the proper estrogenization of vaginal mucosa is important in preoperative and postoperative treatment, increasing the effectiveness of this approach. The objective of this study was the development of intravaginal vaginal suppositories containing DHEA and comparison of the clinical effects of vaginal topical therapy with DHEA, estradiol, or antibiotic after POP surgery. METHOD: Nine types of vaginal suppositories containing 6.5 mg DHEA in different bases were prepared to find optimal formulation for the vaginal conditions. Ninety women referred for POP surgery were randomly assigned to one of three groups receiving topical treatment in the postoperative period (estradiol, DHEA, or antibiotic). On admission to hospital and during follow-up vaginal pH, vaginal maturation index and vaginal symptoms were assessed. RESULTS: Vaginal suppositories with the base made from polyethylene glycol 1,000 without surfactants characterized the highest percentage of the released DHEA. In women treated with topical estradiol or DHEA a significant decrease in the number of parabasal cells, increase in superficial and intermediate cells in the vaginal smears, decrease in vaginal pH, and reduction of vaginal symptoms were observed. CONCLUSIONS: The use of topical therapy with DHEA or the use of topical therapy with estradiol in the postoperative period were both shown to improve maturation index, vaginal pH, and vaginal symptoms. The benefits of topical therapy with DHEA after pelvic organ prolapse repair brings similar results as estradiol, without potential systemic exposure to increased concentrations of sex steroids above levels observed in postmenopausal women.


Assuntos
Desidroepiandrosterona , Estradiol , Prolapso de Órgão Pélvico , Feminino , Humanos , Antibacterianos/uso terapêutico , Desidroepiandrosterona/uso terapêutico , Estradiol/uso terapêutico , Prolapso de Órgão Pélvico/cirurgia , Prolapso de Órgão Pélvico/tratamento farmacológico , Supositórios
3.
J Pharm Biomed Anal ; 230: 115388, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37086553

RESUMO

The knowledge about the stability of compounds and possible ways of their transformation in the process of sample preparation for analysis and during analysis itself is very helpful in the assessment of possible errors which can appear when an accurate and precise estimation of compound concentration in tested samples is attempted. The present paper shows that a significant amount of CBD present in the blood/plasma sample analyzed by means of GC transforms in the hot GC injector not only to 9α-hydroxyhexahydrocannabinol, 8-hydroxy-iso-hexahydrocannabinol, Δ9-tetrahydrocannabinol, Δ8-tetrahydrocannabinol, and cannabinol but also to the trichloroacetic esters of Δ9-THC and Δ8-THC and, unexpectedly, to their dichloroacetic esters when trichloroacetic acid is used as protein precipitation agent. The increase of GC injector temperature favors the formation of dichloroacetic esters of Δ9-THC and Δ8-THC in relation to their trichloroacetic ones. The appearance of dichloroacetic esters of Δ9-THC and Δ8-THC among CBD transformation products is probably the result of the thermal decomposition of their trichloroacetic esters. The transformation of trichloroacetic derivatives of organic compounds into their dichloroacetic derivatives in GC injector has not been reported yet. The instability of trichloroacetic derivatives of Δ8-/Δ9-THC during their GC analysis is probably accounts for the lack of their GC-MS spectra in the databases. NMR, GC-MS and LC-MS spectra of the newly discovered derivatives constitute an important element of the work. The obtained results demonstrate why the use of trichloroacetic acid for plasma samples deproteinization should be avoided when CBD and/or THC are determined by GC.


Assuntos
Canabidiol , Canabidiol/análise , Dronabinol , Artefatos , Ácido Tricloroacético , Canabinol/análise , Canabinol/química
4.
Molecules ; 27(9)2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35566257

RESUMO

This study aimed to evaluate the phenolic profile and biological activity of the extracts from the leaves and fruits of Cotoneaster nebrodensis and Cotoneaster roseus. Considering that miscellaneous species of Cotoneaster are thought to be healing in traditional Asian medicine, we assumed that this uninvestigated species may reveal significant therapeutic properties. Here, we report the simultaneous assessment of chemical composition as well as biological activities (antioxidant, anti-inflammatory, antibacterial, and cytotoxic properties) of tested species. Complementary LC-MS analysis revealed that polyphenols (especially flavonoids and proanthocyanidins) are the overriding phytochemicals with the greatest significance in tested biological activities. In vitro chemical tests considering biological activities revealed that obtained results showed different values depending on concentration, extraction solvent as well as phenolic content. Biological assays demonstrated that the investigated extracts possessed antibacterial properties and were not cytotoxic toward normal skin fibroblasts. Given the obtained results, we concluded that knowledge of the chemical composition and biological activities of investigated species are important to achieve a better understanding of the utilization of these plants in traditional medicine and be useful for further research in their application to treat various diseases, such as skin disorders.


Assuntos
Acne Vulgar , Rosaceae , Acne Vulgar/tratamento farmacológico , Antibacterianos/uso terapêutico , Antioxidantes/química , Frutas/química , Fenóis/análise , Fenóis/farmacologia , Extratos Vegetais/química , Folhas de Planta/química , Rosaceae/química
5.
J Chromatogr A ; 1671: 463020, 2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35405405

RESUMO

The knowledge of compounds stability in the process of sample preparation for analysis and during analysis itself helps assess the accuracy and precision of estimating their concentration in tested samples. The present paper shows that a significant amount of CBD present in the blood/plasma sample analyzed by means of GC transforms in the hot GC injector not only to 9α-hydroxyhexahydrocannabinol, 8-hydroxy-iso-hexahydrocannabinol, delta-9-tetrahydrocannabinol, Δ8-tetrahydrocannabinol, and cannabinol but also to the trifluoroacetic esters of Δ9-THC and Δ8-THC, when trifuoroacetic acid is used as protein precipitation agent. The amount of those newly revealed CBD transformation products depends on the GC injector temperature and on the extrahent type when extracts of the supernatants centrifuged from human plasma samples are analyzed after their preliminary protein precipitation by trifuoroacetic acid. Although trifuoroacetic acid as a protein precipitating agent has many disadvantages, it is quite often used for this purpose due to its very high protein precipitation efficiency. The results presented in the study demonstrate why the use of trifuoroacetic acid for plasma samples deproteinization should be avoided when CBD is determined by GC.


Assuntos
Canabidiol , Artefatos , Canabidiol/análise , Canabinol/análise , Canabinol/química , Dronabinol/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos
6.
J Pharm Biomed Anal ; 204: 114265, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34298472

RESUMO

The paper discusses the matrix effect evoked by oleamide (OLA), a compound frequently found in samples processed and/or stored in lab polypropylene vials or disposable syringes. In the case of many substances a higher response for their samples containing OLA than for net solutions is observed. The analyte signal gain resulting from OLA presence in the examined sample depends on the ratio of OLA concentration to analyte concentration. A characteristic feature of the matrix effect evoked by oleamide is its short duration, which makes the chromatographic data (retention value and signal magnitude of examined compound) repeatable and reproducible. The identified "transient matrix effect" may significantly increase the sensitivity of many analytical procedures employing GC. Evoking the transient matrix effect by means of OLA in the experimental analytical quantitation of cannabidiol in plasma allowed to lower its limit of detection (LOD) by more than 50 %.


Assuntos
Canabidiol , Ácidos Oleicos , Plasma , Xenobióticos
7.
Talanta ; 146: 195-202, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26695252

RESUMO

The main limitation in the standard application of head space analysis employing solid phase microextraction (HS-SPME) for the evaluation of plants as sources of essential oils (EOs) are different quantitative relations of EO components from those obtained by direct analysis of EO which was got in the steam distillation (SD) process from the same plant (EO/SD). The results presented in the paper for thyme, mint, sage, basil, savory, and marjoram prove that the quantitative relations of EO components established by HS-SPME procedure and direct analysis of EO/SD are similar when the plant material in the HS-SPME process is replaced by its suspension in oil of the same physicochemical character as that of SPME fiber coating. The observed differences in the thyme EO composition estimated by both procedures are insignificant (F(exp)

Assuntos
Óleos Voláteis/análise , Óleos Voláteis/isolamento & purificação , Plantas/química , Microextração em Fase Sólida/métodos , Qualidade dos Alimentos
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