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1.
Top Curr Chem (Cham) ; 382(2): 11, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589726

RESUMO

Silicone surfactants have garnered significant research attention owing to their superior properties, such as wettability, ductility, and permeability. Small-molecular silicone surfactants with simple molecular structures outperform polymeric silicone surfactants in terms of surface activity, emulsification, wetting, foaming, and other areas. Moreover, silicone surfactants with small molecules exhibit a diverse and rich molecular structure. This review discusses various synthetic routes for the synthesis of different classes of surfactants, including single-chain, "umbrella" structure, double chain, bolaform, Gemini, and stimulus-responsive surfactants. The fundamental surface/interface properties of the synthesized surfactants are also highlighted. Additionally, these surfactants have demonstrated enormous potential in agricultural synergism, drug delivery, mineral flotation, enhanced oil recovery, separation, and extraction, and foam fire-fighting.


Assuntos
Silicones , Tensoativos , Tensoativos/química , Propriedades de Superfície , Estrutura Molecular
2.
Am J Transl Res ; 13(4): 3780-3786, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34017565

RESUMO

OBJECTIVE: To explore the application of integrated medical and nursing intervention model in radiotherapy for patients with esophageal cancer. METHODS: A total of 78 patients with esophageal cancer undergoing radiotherapy were randomly divided into two groups: control group (n=39, receiving traditional separate medical and nursing management) and study group (n=39, receiving integrated medical and nursing intervention mode). Before and after intervention, the mental state, nutritional index, quality of life and self-efficacy were compared between the two groups, and the adverse reactions were recorded during radiotherapy. RESULTS: Compared with those before intervention, the scores of hamilton anxiety rating scale (HAMA) and hamilton depression scale (HAMD) were lower in both groups when they were discharged from hospital, and the study group was lower than the control group (all P<0.05). The scores of comprehensive quality of life assessment questionnaire (GQOLI-74) and self-management efficacy scale (SUPPH) were increased in both groups, and the study group was higher than the control group (all P<0.05). After intervention for 3 weeks, the levels of Hb, TP and Alb in the two groups were higher than those before intervention, and the study group was higher than the control group (all P<0.05). During radiotherapy, the total incidence of adverse reactions in the study group was lower than that in the control group (P<0.05). CONCLUSION: Integrated medical and nursing intervention can obviously relieve the unhealthy emotion and improve the nutritional status, quality of life and self-efficacy for patients with esophageal cancer undergoing radiotherapy.

3.
J Chromatogr A ; 1109(2): 300-6, 2006 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-16464459

RESUMO

In this paper, novel capillary electrophoresis (CE) methods, which used ionic liquids (1-ethyl-3-methylimidazoium tetrafluoroborate, 1-butyl-3-methylimidazoium tetrafluoroborate), were established to separate and determine some bioactive flavone derivatives in Chinese herb Seriphidium santolinum (Schrenk) Poljak. In order to investigate the traits of ionic liquids in CE, borate was also used as electrolyte to compare with. And the excellence of CE, which used ionic liquids as main running electrolyte and beta-cyclodextrin (beta-CD) as modifier, was illuminated as well. As a result of the study, the difference of ionic liquids and borate in CE was discussed and the advantage of CE, which used ionic liquids as electrolytes for separation, was shown. The analysis was obtained within short time (5-6 min). From the result, it was found that the system, which used ionic liquids, was robust because the joule heating was small. The method of CE, which used ionic liquids, has lower detection limits (0.137-0.642 microg/mL) than that of borate (0.762-1.036 microg/mL). And the CE, which used ionic liquids method, has lower limit of linear range (1.100-2.656 microg/mL), while that of CE, which used borate method, was 2.188-5.313 microg/mL.


Assuntos
Asteraceae/química , Boratos/química , Eletrólitos/química , Eletroforese Capilar/métodos , Flavonas/análise , Íons , beta-Ciclodextrinas
4.
Biomed Chromatogr ; 20(3): 294-300, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16138295

RESUMO

A novel and very simple capillary electrophoretic method for analyzing aconitine components in Aconitum plants was developed using 1-butyl-3-methylimidazoium tetrafluoroborate (1B-3MI-TFB)-based ionic liquid as running electrolyte solution for the first time. The optimum conditions were 35 mM 1B-3MI-TFB solution (pH 8.50) and 15 kV applied voltage. The detection was performed at 254 nm. Aconitine, meaconitine and hypaconitine in Aconitum plants were separated and identified within 5 min. The recoveries were 91.0-103.0% for hypaconitine, 92.8-96.2% for aconitine and 96.0-106.6% for mesaconitine, respectively. Compared with other methods, the analytical time was decreased 4-8-fold and the effect of Joule heating was weaker because the current was smaller.


Assuntos
Aconitina/análise , Alcaloides/análise , Medicamentos de Ervas Chinesas/química , Eletrólitos/química , Eletroforese Capilar/métodos , Imidazóis/química , Concentração de Íons de Hidrogênio , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
5.
Electrophoresis ; 26(22): 4345-54, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16240292

RESUMO

A simple, effective, and continuous online concentration method for the sensitive detection of alkaloids applying CE-flow injection analysis with head-column field-amplified sample stacking was developed. A series of samples was continuously introduced into the capillary by electrokinetic means without interrupting the high voltage. A short water plug was introduced by the EOF at the capillary inlet end prior to sample introduction. Under optimum conditions, 15-fold improvement in concentration sensitivity was achieved, giving an LOD of about 0.67 and 0.73 microg/mL for ephedrine (E) and pseudoephedrine (PE), respectively. The separation could be achieved within 4 min and sample throughput rate could reach up to 7/h. The repeatability (defined as RSD) was 3.62, 1.51% with peak area evaluation and 1.30, 2.58% with peak height evaluation for E and PE, respectively. This method has been successfully applied to the analysis of commercial pharmaceutical preparations containing E and PE, and the recoveries were 92.3-102.4%.


Assuntos
Eletroforese Capilar/instrumentação , Eletroforese Capilar/métodos , Boratos , Soluções Tampão , Efedrina/isolamento & purificação , Concentração de Íons de Hidrogênio
6.
J Chromatogr A ; 1078(1-2): 181-7, 2005 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-16007996

RESUMO

In this paper, a micellar electrokinetic chromatographic (MEKC) method using ionic liquid as modifier for the quantification of the active components of lignans found in the medicinal herbs Schisandra species was developed for the first time. Preliminary investigations employing sodium dodecyl sulfate (SDS) as surfactant did not lead to the necessary resolution of the studied compounds, the addition of ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM-BF4) to the SDS micellar system resulted in the complete separation of all the compounds. The effects on the separation by several parameters such as BMIM-BF4 and SDS concentration, applied voltage, background electrolyte pH and concentration, were evaluated. Under the optimal conditions (5 mM borate-5 mM phosphate buffer in the presence of 20 mM SDS and 10 mM BMIM-BF4, pH 9.2, applied voltage 25 kV and detection at 254 nm), the method successfully applied to the determination of lignans in extracts of Schisandra chinensis (Turcz.) Baill. and Schisandra henryi C.B. Clarke in less than 13 min. The separation mechanism was also discussed.


Assuntos
Cromatografia Capilar Eletrocinética Micelar/métodos , Lignanas/isolamento & purificação , Schisandra/química , Sementes/química , Boratos/química , Soluções Tampão , Concentração de Íons de Hidrogênio , Imidazóis/química , Sensibilidade e Especificidade , Dodecilsulfato de Sódio/química
7.
J Chromatogr A ; 1072(2): 259-65, 2005 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-15887496

RESUMO

A novel, easy and accurate capillary electrophoresis (CE) coupled with flow injection (FI) method for the separation and determination of aspartic acid (Asp) enantiomers by on-line derivatization had been developed, and it had been applied to the real sample for the first time. The derivatization reagents were o-phthalaldehyde (OPA) and mercaptoethanol (ME), which were obtained easily, the chiral selector was beta-cyclodextrin (beta-CD), the micellar chemical was sodium dodecyl sulfate (SDS), and the modifier was methanol. By on-line derivatization, aspartic acid enantiomers were automatically and reproducibly converted to the ultraviolet (UV)-absorbing diastereoisomer derivates, which were separated by micellar electrokinetic chromatography (MEKC). According to the factors affecting the separation and sensitivity of aspartic acid enantiomer and other amino acids in the real sample, the pH value and concentration of the buffer, the concentration of beta-CD and SDS, the volume percentage of the methanol (v/v) in the buffer, the applied voltage and the conversion time were selected as the investigating variates. Under the investigated separation conditions, D-aspartic acid (D-Asp), L-aspartic acid (L-Asp) and other four amino acids achieved the baseline separation in not only the standard mixture of amino acids but also the real sample (Compound Amino Acid Injection (6AA)). The repeatability (defined as relative standard deviation (RSD), n = 5) was 4.0% and 4.0% with peak area evaluation, and 4.2% and 3.7% with peak height evaluation for D-Asp and L-Asp in the real sample. Recovery at added standard levels of 1.0, 3.0 and 6.0 mM was 92%, 104% and 109%, respectively.


Assuntos
Ácido Aspártico/isolamento & purificação , Cromatografia Capilar Eletrocinética Micelar/métodos , Preparações Farmacêuticas/química , Ácido Aspártico/química , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta , Estereoisomerismo
8.
Electrophoresis ; 25(18-19): 3163-7, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15472968

RESUMO

A rapid and selective method is described for the separation of D-aspartic acid (D-Asp) using a continuous on-line derivatization system coupled to capillary electrophoresis (CE). D-Asp was derivatized using o-phthaldialdehyde/N-acetyl-L-cysteine (OPA/NAC). By on-line derivatization, amino acid enantiomers were automatically and reproducibly converted to the UV-absorbing diastereomer derivatives which were separated by capillary zone electrophoresis (CZE) in the presence of 10 mmol/L beta-cyclodextrin (beta-CD). Under the investigated separation conditions, D-Asp is resolved from L-aspartic acid (L-Asp) and other amino acids in a standard mixture of amino acids. The separation could be achieved within 4 min and the sample throughput rate can reach up to 16 h(-1). The repeatability (defined as relative standard deviation, RSD) was 3.21%, 3.58% with peak area evaluation and 3.72%, 4.03% with peak height evaluation for L-Asp and D-Asp.


Assuntos
Ácido D-Aspártico/isolamento & purificação , Eletroforese Capilar/métodos , Calibragem , Eletroforese Capilar/instrumentação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
9.
Talanta ; 63(2): 491-6, 2004 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-18969458

RESUMO

A novel, rapid and accurate method for the separation and determination of aloperine (ALP), sophoridine (SRI), matrine (MT) and oxymatrine (OMT) has been developed by combination of flow injection (FI) with microfluidic capillary electrophoresis (CE) for the first time. In the present paper, a continuous sample introduction interface was described. The interface with an H-channel structure was produced using a non-lithographic approach. The H-channel structure was fixed on a planar plastic base utilizing a horizontal 6.5cm-long separation capillary with two vertical sidearm tubes on each end that served as inlet and outlet flow-through electrode reservoirs. The inlet reservoir also functioned as interface for coupling to the FI system. The buffer solution used was a 50mmoll(-1) borate solution with the pH adjusted to 8.80 with 2moll(-1) HCl. The performance of the system was demonstrated in the separation and determination of ALP, SRI, MT and OMT with UV detection at 215nm, achieving baseline separation within 2min. A series of samples was injected repeatedly without current interruption and subsequent rinsing, and the contents of these four bio-alkaloids in two marketed drugs were determined with satisfactory recovery by this proposed method.

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