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2.
Pharmeur Bio Sci Notes ; 2021: 157-166, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34751647

RESUMO

The European Pharmacopoeia (Ph. Eur.), includes both individual monographs on essential oils and a general monograph that covers all essential oils for pharmaceutical use, whether covered by an individual monograph or not. The individual monographs generally describe gas chromatography as a first identification test, while thin-layer chromatography (TLC) and high-performance thin-layer chromatography (HPTLC) methods are included in the second identification series. To comply with Ph. Eur. general chapter 2.8.25. High-performance thin-layer chromatography of herbal drugs and herbal drug preparations, HPTLC parameters must be standardised. Currently, 18 of the 32 monographs on essential oils feature the same TLC/HPTLC method, but differ in terms of the other conditions described. A single, standardised chromatographic system with a system suitability test (SST) and intensity markers for all 32 essential oils covered by individual monographs would be desirable, particularly for pharmacies and other users that cannot perform gas chromatography for financial reasons. To this end, this paper describes the development of a general HPTLC method for the identification of essential oils in compliance with general chapter 2.8.25. The method proposes the use of ethyl acetate, toluene (5:95 V/V) as mobile phase, isoeugenol/isoeugenyl acetate for the SST, and a combination of one alcohol (either borneol or linalool) and one ester (either linalyl acetate or bornyl acetate) as intensity markers.


Assuntos
Óleos Voláteis , Plantas Medicinais , Cromatografia em Camada Delgada
3.
Anal Sci ; 37(11): 1491-1495, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34690230

RESUMO

Matrix-assisted laser desorption/ionization-based mass spectrometry imaging (MSI) of separated lipids on thin-layer chromatography (TLC) plates or followed by blotted hydrophilic polyvinylidene fluoride (PVDF) membranes has become a powerful tool in lipidomic analyses. However, background peaks in MS spectra often cover lipid peaks in a low amount/ionization effect; consequently, only low intensities/resolutions MSI are obtained. To address the aforementioned problem, we attempted 1,2-dichloroethane pre-washing of TLC plates before development and found that backgrounds could successfully be removed from the TLC plate or PVDF membrane.


Assuntos
Glicerol , Glicoesfingolipídeos , Cromatografia em Camada Delgada , Ésteres , Dicloretos de Etileno , Ácidos Graxos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
4.
J Agric Food Chem ; 69(43): 12686-12694, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34665636

RESUMO

Root extracts of three goldenrods were screened for antimicrobial compounds. 2Z,8Z- and 2E,8Z-matricaria esters from European goldenrod (Solidago virgaurea) and E- and Z-dehydromatricaria esters from grass-leaved goldenrod (Solidago graminifolia) and first from showy goldenrod (Solidago speciosa) were identified by high-performance thin-layer chromatography combined with effect-directed analysis and high-resolution mass spectrometry or nuclear magnetic resonance spectroscopy after liquid chromatographic fractionation and isolation. Next to their antibacterial effects (against Bacillus subtilis, Aliivibrio fischeri, and Pseudomonas syringae pv. maculicola), they inhibited the crop pathogenic fungi Fusarium avenaceum and Bipolaris sorokiniana with half maximal inhibitory concentrations (IC50) between 31 and 107 µg/mL. Benzyl 2-hydroxy-6-methoxybenzoate, for the first time found in showy goldenrod root, showed the strongest antifungal effect, with IC50 of 25-26 µg/mL for both fungal strains.


Assuntos
Solidago , Antibacterianos/farmacologia , Cromatografia em Camada Delgada , Fungos , Fusarium , Extratos Vegetais/farmacologia
5.
Anal Chim Acta ; 1182: 338950, 2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34602191

RESUMO

The powerful fusion of on-surface synthesis and effect-directed analysis was introduced as novel tool for synthetic drug discovery, all on the same high-performance thin-layer chromatography plate. Precise automated sample application allowed both, high-throughput chemistry of 60 reactions at once and reaction miniaturization down to the 15-nmol scale. The antibiotic activity of all on-surface synthesized compounds was evaluated on the same surface via the Gram-positive Bacillus subtilis bioassay. For one product, synthesis (reaction, purification and identification) took 5.3 min and semi-quantitative biological evaluation took 2.8 min. Out of 60 on-surface reactions 10 products (17%) were identified to be more active than a well-known antibiotic reference. The concept was transferred to the Gram-negative Aliivibrio fischeri bioassay. For the first time, a new analytical platform was shown for a streamlined workflow at the most miniaturized scale from synthesis, purification, identification and quantification to semi-quantitative biological activity evaluation (all on the same chromatography plate).


Assuntos
Descoberta de Drogas , Extratos Vegetais , Bioensaio , Cromatografia em Camada Delgada , Espectrometria de Massas
6.
Molecules ; 26(19)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34641345

RESUMO

The fractionation of the methanolic extract (MeOH-E) of Retama raetam (Forssk.) Webb & Berthel and further analysis by thin layer chromatography resulted in four fractions (F1, F2, F3 and F4) that, in parallel with the MeOH-E, were screened for antioxidant, cytotoxic, antidiabetic and antibacterial properties. In addition, chemical characterization of their bioactive molecules was performed using LC-DAD-ESI/MSn. The results indicated that F3 was the most promising regarding antioxidant and cytotoxicity abilities, possibly due to its richness in flavonoids class, particularly isoflavones. In turn, F1 was characterized by the presence of the most polar compounds from MeOH-E (organic acids and piscidic acid) and showed promising abilities to inhibit α-amylase, while F4, which contained prenylated flavonoids and furanoflavonoids, was the most active against the tested bacteria. The gathered results emphasize the distinct biological potentials of purified fractions of Retama raetam.


Assuntos
Antibacterianos/farmacologia , Fracionamento Químico/métodos , Fabaceae/química , Flavonoides/farmacologia , Células A549 , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antioxidantes , Compostos de Bifenilo/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cromatografia em Camada Delgada , Flavonoides/química , Flavonoides/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Picratos/química , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento
7.
Molecules ; 26(19)2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34641608

RESUMO

The effect of spontaneous fermentation by lactic acid bacteria on the extraction yield of bioactive compounds and antioxidant activity from rosemary leaf extracts was investigated using high-performance thin-layer chromatography (HPTLC). Brining and spontaneous fermentation with lactic acid bacteria more than doubled extraction of polyphenolics and antioxidants from the rosemary leaves. The results show that lactic acid fermentation enhances antioxidant activity in extracts by increasing the total phenolic content but does not increase extraction of phytosterols. Increased extraction of phenolic oxidants during fermentation assisted extraction, results from the in situ generated natural eutectic solvent from the plant sample. ATR-FTIR spectra from the bioactive bands suggests that this increased antioxidant activity is associated with increased extraction of rosmarinic acid, depolymerised lignin, abietane diterpenoids and 15-hydroxy-7-oxodehydroabietic acid.


Assuntos
Antioxidantes/química , Antioxidantes/metabolismo , Lactobacillales/metabolismo , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Rosmarinus/química , Rosmarinus/metabolismo , Abietanos/química , Abietanos/metabolismo , Cromatografia em Camada Delgada , Cinamatos/química , Cinamatos/metabolismo , Depsídeos/química , Depsídeos/metabolismo , Fermentação , Humanos , Lignina/química , Lignina/metabolismo , Fenóis/química , Fenóis/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
8.
J Chromatogr A ; 1655: 462488, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34474191

RESUMO

A densitometry method based on steady-state and time-resolved fluorescence assessments for thioridazine and its photoproducts applied on HPTLC plates has been developed. The excitation source was a picosecond diode laser emitting at 375 nm. This method was used for the analysis of the photoproducts resulted from thioridazine irradiation with 266 nm nanosecond-pulsed laser. The validation of the developed method was performed for thioridazine in terms of linearity, precision, limits of detection and quantification. Furthermore, analysis of the photoproducts of irradiated thioridazine was performed by steady-state and time-resolved fluorescence. The fluorescence spectra and fluorescence lifetime of each photoproduct were obtained and the horizontal chromatograms of fluorescence maxima were generated.


Assuntos
Lasers , Tioridazina , Cromatografia em Camada Delgada , Densitometria
9.
Artigo em Inglês | MEDLINE | ID: mdl-34592686

RESUMO

The proliferation of chimeric antigen receptor (CAR) T cells is closely related to their efficacy, but it is still a great challenge to monitor and quantify CAR T cells in vivo. Based on the high affinity (Kd ≈ 10-15 M) of streptavidin (SA) and biotin, radiolabeled biotin may be used to quantify SA-transduced CAR T cells (SA-CAR T cells). Radio-thin-layer chromatography (radio-TLC) and positron emission tomography (PET) are highly sensitive for trace analysis. Our aim was to develop radio-TLC and PET methods to quantify SA-CAR T cells in vitro and in vivo. First, we developed [68Ga]-DOTA-biotin. Commercially available SA was used as a standard, and quantitative standard curves were established in vitro and in vivo by radio-TLC and PET. Furthermore, the feasibility of the method was verified in Raji model mice. The linear range of radio-TLC was 0.02 âˆ¼ 0.15 pmol/µL with R2 = 0.9993 in vitro. The linear range of PET was 0.02 âˆ¼ 0.76 pmol/µL with R2 = 0.9986 in vivo. SA in CAR T cells can also be accurately quantified in a Raji leukemia model according to PET imaging. The radio-TLC/PET method established in this study is promising for using in the dynamic monitoring and analysis of SA-CAR T cells during therapy.


Assuntos
Cromatografia em Camada Delgada/métodos , Tomografia por Emissão de Pósitrons/métodos , Receptores de Antígenos Quiméricos/química , Estreptavidina/farmacologia , Linfócitos T , Animais , Biotina/análogos & derivados , Feminino , Camundongos , Compostos Organometálicos , Reprodutibilidade dos Testes , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo
10.
J Agric Food Chem ; 69(38): 11272-11281, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34546731

RESUMO

The European Union banned the usage of antibiotic growth promoters in animal production. The probiotic microorganism of the genus Bacillus appeared to be an attractive candidate to replace antibiotics. The Bacillus subtilis DSM 29784 is one of these strains. To date, the probiotic effect has not been completely understood, but it is supposed that the effect depends on metabolites of the microorganism. Imaging high-performance thin-layer chromatography (HPTLC) is a powerful tool to visualize differences in the metabolite profile of bacteria with high genetic similarity to allow a better understanding of the probiotic effect. In comparison to other bacteria, especially these bacterial cells were more robust to harsh cultivation conditions and produced a higher level of antioxidants or bioactive substances such as surfactin. HPTLC enabled the comparison of pure cell cultures to the spore cultivation in the feed, and the results explain and support the probiotic effect.


Assuntos
Bacillus , Probióticos , Ração Animal , Animais , Antibacterianos , Bacillus subtilis , Cromatografia em Camada Delgada
11.
BMC Res Notes ; 14(1): 348, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34496958

RESUMO

OBJECTIVE: Papaver decaisnei Hochst. & Steud. Ex Elkan and Papaver glaucum Boiss. & Hausskn. growing wild in Northern Iraq have been historically used for medicinal purposes. In this study, both species were evaluated for their alkaloid content and antimicrobial activities. RESULTS: Alkaloids were extracted and isolated by preparative thin-layer chromatography (TLC). Identification was carried out by comparing spectral data (UV and 1H-NMR) and TLC Rf values with those of authentic samples. Two alkaloids, proapaorphine-type mecambrine and aporphine-type roemerine were isolated from P. decaisnei. Two benzylisoquinoline type alkaloids papaverine (major alkaloid) and palaudine as well as aporphine-type N-methylasimilobine have been obtained in P. glaucum. Both P. glaucum and P. decaisnei extracts revealed strong antimicrobial activity on Pseudomonas aeruginosa ATCC 27853 and Enterococcus faecalis ATCC 29212. Collectively these results indicate that P. glaucum and P. decaisnei are promising sources of alkaloids that could further be investigated for medicinal purposes.


Assuntos
Alcaloides , Anti-Infecciosos , Papaver , Alcaloides/farmacologia , Anti-Infecciosos/farmacologia , Cromatografia em Camada Delgada , Extratos Vegetais/farmacologia
12.
Anal Chim Acta ; 1180: 338644, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34538319

RESUMO

Among the analytical advances, hyphenated HPTLC offers great potential for solving pressing questions. It provides straightforward information about effects arising from individual compounds in complex or natural samples separated in parallel. The chromatographic separation is combined with effect-directed detection using enzymatic or biological assays. This helps to select from the thousands of compounds in a sample the important ones that need to be further characterized using high-resolution mass spectrometry. Unique benefits are discussed exemplarily arising from its super-hyphenation, minimum requirements for sample preparation, detection of multi-modulating compounds or agonistic versus antagonistic effects, and miniaturized on-surface metabolization. HPTLC stands for a versatile, creative and flexible open-format technique. As miniaturized open-source LabToGo system, it shows the potential to be applied as Citizen Science.


Assuntos
Bioensaio , Cromatografia em Camada Delgada , Espectrometria de Massas
13.
Int J Mol Sci ; 22(18)2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34576167

RESUMO

Shiga toxin (Stx) is released by enterohemorrhagic Escherichia coli (EHEC) into the human intestinal lumen and transferred across the colon epithelium to the circulation. Stx-mediated damage of human kidney and brain endothelial cells and renal epithelial cells is a renowned feature, while the sensitivity of the human colon epithelium towards Stx and the decoration with the Stx receptor glycosphingolipids (GSLs) globotriaosylceramide (Gb3Cer, Galα1-4Galß1-4Glcß1-1Cer) and globotetraosylceramide (Gb4Cer, GalNAcß1-3Galα1-4Galß1-4Glcß1-1Cer) is a matter of debate. Structural analysis of the globo-series GSLs of serum-free cultivated primary human colon epithelial cells (pHCoEpiCs) revealed Gb4Cer as the major neutral GSL with Cer (d18:1, C16:0), Cer (d18:1, C22:1/C22:0) and Cer (d18:1, C24:2/C24:1) accompanied by minor Gb3Cer with Cer (d18:1, C16:0) and Cer (d18:1, C24:1) as the dominant lipoforms. Gb3Cer and Gb4Cer co-distributed with cholesterol and sphingomyelin to detergent-resistant membranes (DRMs) used as microdomain analogs. Exposure to increasing Stx concentrations indicated only a slight cell-damaging effect at the highest toxin concentration of 1 µg/mL for Stx1a and Stx2a, whereas a significant effect was detected for Stx2e. Considerable Stx refractiveness of pHCoEpiCs that correlated with the rather low cellular content of the high-affinity Stx-receptor Gb3Cer renders the human colon epithelium questionable as a major target of Stx1a and Stx2a.


Assuntos
Colo/metabolismo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Globosídeos/metabolismo , Toxina Shiga/metabolismo , Triexosilceramidas/metabolismo , Linhagem Celular , Células Cultivadas , Cromatografia em Camada Delgada , Glicoesfingolipídeos/metabolismo , Humanos , Espectrometria de Massas , Sintaxina 1/metabolismo
14.
J Pharm Biomed Anal ; 206: 114358, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34534866

RESUMO

The chromatographic and lipophilicity characters of seven cephalosporins of different four classes (cephradine, cefaclor, cefprozil, cefixime, cefotaxime, ceftazidime and cefepime) were examined by salting out thin-layer chromatography (SOTLC). SOTLC using ammonium sulfate salt was employed to predict the lipophilicity of the proposed drugs via their retention behavior. The calculated RM0 values showed liner relationship with the molar concentration of ammonium sulfate in mobile phase in the range of 0.5-2.5 mol/L. Additionally, quantitative structure retention relationship (QSRR) was generated to figure out the relationship between the calculated chromatographic parameters (RM0 and C0) and log P of the studied cephalosporins. Good correlations were found between the chromatographically obtained retention parameters (RM0 and C0) and some molecular descriptors of the examined drugs. Furthermore, an efficient QSAR model was carried out using the calculated chromatographic parameters (RM0 and C0) and log P of the studied cephalosporins to predict minimum inhibitory concentration (MIC) and blood brain barrier (BBB) penetration of the examined drugs. The study was extended to separate and quantify the selected antibiotics in their pure forms and pharmaceutical formulations. Normal phase thin layer chromatographic (NP-TLC) method using a usable developing system of acetone: methanol: water: ammonium hydroxide: glacial acetic acid (90: 10: 18: 3: 2, by volume) was successfully applied to resolve the studied cephalosporins. Linearity was achieved in the range of 0.2-3 µg/mL for most of the studied antibiotics. The developed SOTLC method can be considered as a good start alternative to reversed phase thin layer chromatography (RP-TLC) for prediction of the lipophilic properties of examined cephalosporins. Moreover, the proposed NP-TLC densitometric method can be easily applied for quality control analysis of the chosen drugs and other structurally related components.


Assuntos
Cefalosporinas , Cromatografia de Fase Reversa , Cefepima , Cromatografia em Camada Delgada , Testes de Sensibilidade Microbiana
15.
Artigo em Inglês | MEDLINE | ID: mdl-34371347

RESUMO

Ephedra herb extracts are being extensively investigated in terms of their antioxidative, antimicrobial and antiproliferative properties, with phenolic components being the general carriers of these bioactivities. Here we describe a comprehensive set of analytical methods employed to determine and characterize both the antioxidative activity and the qualitative profile of phenolic acids and flavonoids present in several Ephedra species of different geographical origin. Spectrophotometric methods were used to determine the total phenolic content, total flavonoid content and antioxidative activity. Multi-development HPTLC enabled chemical fingerprinting which can be used for species differentiation. Individual spots of the thin-layer chromatogram were subjected to GC-MS with injection port derivatization for identification, which was based on both the detected mass spectra and recorded retention indices. The results were compared and complemented with GC-MS using offline derivatization.


Assuntos
Antioxidantes , Cromatografia em Camada Delgada/métodos , Ephedra/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Fenóis , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Flavonoides/química , Flavonoides/isolamento & purificação , Fenóis/análise , Fenóis/química , Fenóis/isolamento & purificação
16.
Molecules ; 26(15)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34361800

RESUMO

Thin-layer chromatography (TLC) bioautography is an evolving technology that integrates the separation and analysis technology of TLC with biological activity detection technology, which has shown a steep rise in popularity over the past few decades. It connects TLC with convenient, economic and intuitive features and bioautography with high levels of sensitivity and specificity. In this study, we discuss the research progress of TLC bioautography and then establish a definite timeline to introduce it. This review summarizes known TLC bioautography types and practical applications for determining antibacterial, antifungal, antitumor and antioxidant compounds and for inhibiting glucosidase, pancreatic lipase, tyrosinase and cholinesterase activity constitutes. Nowadays, especially during the COVID-19 pandemic, it is important to identify original, natural products with anti-COVID potential compounds from Chinese traditional medicine and natural medicinal plants. We also give an account of detection techniques, including in situ and ex situ techniques; even in situ ion sources represent a major reform. Considering the current technical innovations, we propose that the technology will make more progress in TLC plates with higher separation and detection technology with a more portable and extensive scope of application. We believe this technology will be diffusely applied in medicine, biology, agriculture, animal husbandry, garden forestry, environmental management and other fields in the future.


Assuntos
Cromatografia em Camada Delgada/métodos , Descoberta de Drogas/métodos , Medições Luminescentes/métodos , Animais , Anti-Infecciosos/isolamento & purificação , Antineoplásicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Inibidores Enzimáticos/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana/métodos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Sensibilidade e Especificidade
17.
Food Res Int ; 147: 110455, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34399456

RESUMO

Passiflora species, mangosteen, and cherimoya peels are a source of bioactive phenolic compounds. Nevertheless, a significant fraction of polyphenols, called non-extractable polyphenols (NEPs), are retained in the extraction residue after a conventional extraction. Thus, alkaline, acid, and enzymatic-assisted extractions to recover high contents of antioxidant NEPs from the extraction residue of fruit peels, were compared in this work. A high-performance thin-layer chromatography method with UV/Vis detection was developed in order to obtain the phenolic profile for the extracts. The most intense bands were further analyzed by direct analysis in real-time-high-resolution mass spectrometry to tentatively identified NEPs in fruit peel extracts. Total phenolic and proanthocyanidin contents and antioxidant capacity of the extracts were measured to carry out a multivariate statistical analysis. Alkaline hydrolysis was the most efficient treatment to recover NEPs from fruit peels as well as a promising treatment to obtain antioxidant extracts along with EAE. Cherimoya peel extracts were the richest in antioxidant NEPs. This work highlights that many NEPs remain on the extraction residue of fruit peels after conventional extraction and are not usually taken into account.


Assuntos
Frutas , Polifenóis , Cromatografia em Camada Delgada , Frutas/química , Espectrometria de Massas , Extratos Vegetais , Polifenóis/análise
18.
Molecules ; 26(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34443322

RESUMO

The main aim of this study was to develop a method for the isolation and determination of polyphenols-in particular, flavonoids present in various morphological parts of plants belonging to the cabbage family (Brassicaceae). Therefore, a procedure consisting of maceration, acid hydrolysis and measurement of the total antioxidant capacity of plant extracts (using DPPH assay) was conducted. Qualitative analysis was performed employing thin-layer chromatography (TLC), which was presented to be a suitable methodology for the separation and determination of chemopreventive phytochemicals from plants belonging to the cabbage family. The study involved the analysis of 25 vegetal samples, including radish, broccoli, Brussels sprouts, kale, canola, kohlrabi, cabbage, Chinese cabbage, red cabbage, pak choi and cauliflower. In addition, selected flavonoids content in free form and bonded to glycosides was determined by using an RP-UHPLC-ESI-MS/MS method.


Assuntos
Brassicaceae/química , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/isolamento & purificação , Cromatografia em Camada Delgada
19.
J Chromatogr A ; 1654: 462461, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34438305

RESUMO

The characterization and quality control of natural herbal medicines, such as traditional Chinese medicines (TCMs), is of great significance to ensure their potential efficacy and avoid severe side effects. Thin-layer chromatography (TLC) is a simple and classic approach for examining quality marker of natural products. Nevertheless, it is more difficult to further characterize the compounds adsorbed on the TLC plate. Herein, we reported a simple setup of laser ablation-assisted direct analysis in real-time mass spectrometry (LA-DART-MS), in which the coupling of mass spectrometry information to provide a predominant dimension in the identification of unknown chemical compositions separated on standard TLC plates, and it was applied for rapid characterization of various kinds of natural herbal medicines. The results showed that the introduction of low-cost small laser pointer had significantly improved the desorption process. The system was successfully applied in the analysis of alkaloids, flavonoids, anthraquinones, volatile oils, glycosides, organic acids, and eight different TCMs including Sophorae Flavescentis Radix, Angelicae Sinensis Radix, Acori Tatarinowii Rhizoma, Phellodendri Chinensis Cortex, Picrasmae Ramulus et Folium, Gynura Japonica, Rhei Radix et Rhizoma and Dendrobii Caulis. The obtained limits of detection (LODs) of this method for various types of reference substances were in the range of 4.6-162.2 ng/band on TLC plates. Furthermore, the quality control and identification of different species of Dendrobii Caulis herb was achieved. This study combines the advantages of TLC and ambient mass spectrometry to provide a good choice for the screening and identification of active ingredients and the quality evaluation of botanical samples.


Assuntos
Química Farmacêutica , Cromatografia em Camada Delgada , Espectrometria de Massas , Plantas Medicinais , Química Farmacêutica/métodos , Lasers , Plantas Medicinais/química
20.
Anal Methods ; 13(34): 3779-3784, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34350441

RESUMO

This research paper presents simple and quick eco-friendly spot test and spectrophotometric methods for the determination of L-glutathione. The spot test assay is based on the formation of a color complex with phenazine methosulphate and L-glutathione on a thin-layer chromatography plate followed by image analysis using a scanner as a detector. For analysis, the image was converted into red, green, and blue (RGB) histograms. A series of parameters that influenced the color formation were investigated, and under the optimal conditions, a good linearity was observed in the range of 200-1000 µg mL-1 and 249-1000 µg mL-1 of L-glutathione with correlation coefficients of 0.9907 for B and 0.9903 for G channels. For the spectrophotometric method, a good linearity was obtained in the range of 2.1-60 µg mL-1 of L-glutathione concentration with a correlation coefficient of 0.9961. A mechanism of the reaction of L-glutathione with phenazine was proposed and confirmed by Fourier transform infrared and mass spectroscopy.


Assuntos
Glutationa , Fenazinas , Cromatografia em Camada Delgada , Metilfenazônio Metossulfato , Espectrofotometria
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