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1.
Zhongguo Zhong Yao Za Zhi ; 48(21): 5863-5870, 2023 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-38114182

RESUMO

This study aims to investigate the effects of baicalein(BAI) on lipopolysaccharide(LPS)-induced human microglial clone 3(HMC3) cells, with a focus on suppressing inflammatory responses and elucidating the potential mechanism underlying the therapeutic effects of BAI on ischemic stroke via modulating the cAMP-PKA-NF-κB/CREB pathway. The findings have significant implications for the application of traditional Chinese medicine in treating cerebral ischemic diseases. First, the safe dosage of BAI was screened, and then an inflammation model was established with HMC3 cells by induction with LPS for 24 h. The cells were assigned into a control group, a model group, and high-, medium-, and low-dose(5, 2.5, and 1.25 µmol·L~(-1), respectively) BAI groups. The levels of superoxide dismutase(SOD) and malondialdehyde(MDA) in cell extracts, as well as the levels of interleukin-1ß(IL-1ß), IL-6, tumor necrosis factor-α(TNF-α), and cyclic adenosine monophosphate(cAMP) in the cell supernatant, were measured. Western blot was performed to determine the expression of protein kinase A(PKA), phosphorylated cAMP-response element binding protein(p-CREB), and nuclear factor-kappa B p65(NF-κB p65). Hoechst 33342/PI staining was employed to assess cell apoptosis. High and low doses of BAI were used for treatment in the research on the mechanism. The results revealed that BAI at the concentrations of 10 µmol·L~(-1) and below had no impact on normally cultured HMC3 cells. LPS induction at 200 ng·mL~(-1) for 24 h reduced the SOD activity and increased the MDA content in HMC3 cells. However, 5, 2.5, and 1.25 µmol·L~(-1) BAI significantly increased the SOD activity and 5 µmol·L~(-1) BAI significantly decreased the MDA content. In addition, BAI ameliorated the M1 polarization of HMC3 cells induced by LPS, as indicated by cellular morphology. The results of ELISA demonstrated that BAI significantly lowered the levels of TNF-α, IL-1ß, IL-6, and cAMP in the cell supernatant. Western blot revealed that BAI up-regulated the protein levels of PKA and p-CREB while down-regulating the expression of NF-κB p65. Hoechst 33342/PI staining results indicated that BAI mitigated the apoptosis of HMC3 cells. Overall, the results indicated that BAI had protective effects on the HMC3 cells induced by LPS, and could inhi-bit inflammatory response and improve cell apoptosis, which might be related to the regulation of the cAMP-PKA-NF-κB/CREB pathway.


Assuntos
Microglia , NF-kappa B , Humanos , NF-kappa B/genética , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Superóxido Dismutase/metabolismo
2.
Zhongguo Zhong Yao Za Zhi ; 47(19): 5365-5374, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36472044

RESUMO

This study aims to assess the efficacy and safety of Hulisan Capsules in the treatment of knee osteoarthritis, which is expected to serve as a reference for clinical practice. To be specific, randomized controlled trial(RCT) on the treatment of knee osteoarthritis with Hulisan Capsules was retrieved from EMbase, PubMed, Cochrane Library, Web of Science, CNKI, Wanfang, SinoMed, and VIP(from inception to November 15, 2021). Two researchers independently screened the articles, extracted the data, and evaluated the risk of bias with ROB. RevMan 5.4 was used for Meta-analysis. Finally, 12 RCTs were screened out, involving 1 703 cases(1 075 in the experimental group and 628 in the control group). Meta-analysis showed that conventional treatment + Hulisan Capsules was superior to conventional treatment alone in terms of symptom relief rate(RR=1.19, 95%CI[1.09, 1.30], P<0.000 1), Lysholm score(MD=11.17, 95%CI[7.35, 15.00], P<0.000 01), visual analogue scale(VAS) score(MD=-0.99, 95%CI[-1.30,-0.68], P<0.000 01), and knee function score(RR=8.94, 95%CI[6.51, 11.37], P<0.000 01). Hulisan Capsules alone was superior to the conventional treatment alone in terms of the symptom relief rate(RR=1.38, 95%CI[1.13, 1.69], P=0.002) and knee function score(MD=2.88, 95%CI[0.81, 4.94], P=0.006), but VAS score was insignificantly different between the patients treated with Hulisan Capsules alone and those with conventional treatment alone(MD=-0.57, 95%CI[-1.42, 0.29], P=0.19). Hulisan Capsules + conventional treatment showed insignificant difference in symptom relief rate from the Zhuifeng Tougu Capsules + conventional treatment(RR=1.07, 95%CI[0.91, 1.25], P=0.44). The Lequesne score was insignificantly different between Hulisan Capsules + conventional treatment and conventional treatment/Zhuifeng Tougu Capsules + conventional treatment(MD=-2.17, 95%CI[-6.29, 1.96], P=0.30). The incidence of adverse reactions in the experimental group was significantly lower than control group(RR=0.57, 95%CI[0.34, 0.96], P=0.03). According to the available data and methods, Hulisan Capsules/Hulisan Capsules + conventional treatment could improve the symptom relief rate, Lysholm score, knee function score, and VAS score of patients with knee osteoarthritis, and alleviate the symptoms of pain, stiffness, and swelling of them. No serious adverse reactions were found yet. In the future, more large-sample and standard clinical trials are needed to verify the effect and safety of Hulisan Capsules in the treatment of knee osteoarthritis.


Assuntos
Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/tratamento farmacológico , Cápsulas , Dor
3.
Zhongguo Zhong Yao Za Zhi ; 46(21): 5450-5455, 2021 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-34951195

RESUMO

Pharmacovigilance system is an extension of the original adverse drug reactions monitoring and reporting system as well as an internationally recognized basic system that must be matched with the whole life cycle supervision of drugs. European Union(EU)pharmacovigilance system, World Health Orgnization(WHO) Uppsala Monitoring Center system and ICH system are internationally recognized pharmacovigilance systems. They all have their own pharmacovigilance characteristics and could provide guarantee for clinical safe drug use. With the deepening of international communication, pharmacovigilance has also been developed in China. Pharmacovigilance of Chinese medicine is a new concept based on the existing pharmacovigilance system of chemical medicine and the characteristics of Chinese medicine. In ancient China, Chinese medicine also had its own ways of early warning. Ancient medical books have records on the toxicity classification, clinical pharmacovigilance and intoxication rescue of Chinese medicine. With the increase of public recognition of Chinese medicine in recent years, especially since the government issued the 13 th Five-Year Plan for the development of Chinese medicine, the pharmaceutical industry in China has paid more and more attention to the pharmacovigilance of Chinese medicine.However, the pharmacovigilance system of Chinese medicine has not yet been established, and it still needs to be explored and improved.Therefore, it is very necessary to develop the system to standardize pharmacovigilance-related activities of Chinese medicine. In this context, this study analyzed and learned the characteristics of pharmacovigilance systems of EU, ICH, and WHO Uppsala Monitoring Center, so as to provide some enlightenment for the establishment and improvement of pharmacovigilance system of Chinese medicine.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Farmacovigilância , Sistemas de Notificação de Reações Adversas a Medicamentos , Livros , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , União Europeia , Humanos , Medicina Tradicional Chinesa
4.
Complement Ther Med ; 52: 102456, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32951717

RESUMO

OBJECTIVE: This study used a prospective cohort study to observe the effect of triple-negative breast cancer on the 2-year disease-free survival rate with or without "TCM formula". METHODS: From November 1 st, 2016, the first patient was enrolled in the cohort study. A total of 356 patients were enrolled on January 30, 2019. Among them, 154 cases were followed up for 2 years. During the follow-up, there were 6 cases of shedding, so 6 cases were affected. A total of 148 cases were included in the analysis, including 73 in the exposed group and 75 in the non-exposed group. The exposed group was given "TCM formula" on the basis of standardized treatment, and the non-exposed group was treated with simple triple-negative breast cancer. The two groups visited each of the three months. The interview included safety examination (hematology and imaging). The endpoint was the difference in 2-year invasive disease-free survival between the exposed and non-exposed groups and the safety of the "TCM formula". RESULTS: There were 6 cases of shedding during the experiment and the shedding rate was 3.9 %. The 2-year rate of invasive disease-free survival in the exposed team was 88.7 % and the non-exposed group was 82.5 %. Logistic multivariate regression analysis predicted that "TCM formula" could reduce the disease-related recurrence and metastasis rate by 11 % (OR = 0.89, 95 % CI 0.37-0.956, P<0.05). Through K-M survival analysis, TNBC patients with age ≤35 years and regional lymph node stage N1 may be the benefit group of "TCM formula"(P<0.05). During the study, the incidence of total adverse events was 8.2 % in the exposed group, mainly manifested as stomach discomfort, diarrhea, and hepatocyte damage. CONCLUSION: 1. In the exposed group, the two-year rate of invasive disease-free survival increased by 6.2 % compared with the non-exposed group(P>0.05). 2. According to K-M survival analysis, TNBC patients with age ≤35 years and regional lymph node metastasis to N1 may be potential beneficiaries of "TCM formula". 3. "TCM Formula" is safe and tolerable to most patients.


Assuntos
Medicina Tradicional Chinesa/métodos , Metástase Neoplásica/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/mortalidade , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/mortalidade , Adulto , Idoso , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Sobrevida
5.
Cancer Manag Res ; 11: 299-307, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30643455

RESUMO

PURPOSE: To assess the efficacy, safety, and quality-of-life impact of switching adjuvant treatment in hormone receptor-positive primary breast cancer patients who are still premenopausal after 2-3 years of tamoxifen therapy to anastrozole plus goserelin as compared with continuing tamoxifen over a total period of 5 years. PATIENTS AND METHODS: Hormone receptor-positive, premenopausal, lymph node-positive, or tumor size ≥4 cm breast cancer patients who had received tamoxifen for 2-3 years were randomly assigned to continue tamoxifen treatment (TAM group) or switch to adjuvant anastrozole plus goserelin (ADD group) and continue treatment for another 2-3 years (total treatment duration 5 years). Endpoints evaluated were adverse events (AEs), changes in bone mineral density, quality of life, and disease-free survival-related events. RESULTS: A total of 62 patients (33 in the ADD group and 29 in the TAM group) were evaluated. Grade 3-4 drug-related AEs occurred in five patients (15.2%) in the ADD group vs none in the TAM group. In the ADD group, arthralgias were the most common AEs (5/33 patients; 15.2%), and three patients in this group were discontinued because of AEs. Treatment was temporarily suspended due to AEs in three patients (9.1%) in the ADD group and one patient (3.4%) in the TAM group. Compared with continuing TAM therapy, switching to anastrozole plus goserelin did not result in any worsening of bone mineral density or quality of life. During a median follow-up of 34 months, five patients (15.2%) in the ADD group had disease-free survival events vs four patients (13.8%) in the TAM group. CONCLUSION: For early-stage breast cancer patients who remain premenopausal following 2-3 years of adjuvant tamoxifen therapy, switching to anastrozole plus goserelin therapy was safe with tolerable adverse effects. However, it did not show superior efficacy compared to remaining on tamoxifen treatment. TRIAL REGISTRATION: ClinicalTrials.gov (identifier NCT01352091).

6.
Chin J Integr Med ; 21(5): 361-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25776841

RESUMO

OBJECTIVE: To investigate whether I-tetrahydropalmatine (I-THP), an alkaloid mainly present in Corydalis family, could ameliorate early vascular inflammatory responses in atherosclerotic processes. METHODS: Fluorescently labeled monocytes were co-incubated with human umbilical vein endothelial cells (HUVECs), which were pretreated with I-THP and then simulated with tumor necrosis factor (TNF)-α in absence of I-THP to determine if I-THP could reduce thecytokine-induced adhesion of monocytes to HUVECs. Then I-THP were further studied the underlying mechanisms through observing the transcriptional and translational level of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) and the nuclear translocation of nuclear factor (NF)-κ B in HUVECs. RESULTS: L-THP could block TNF-α-induced adhesion of monocytes to HUVECs and could significantly inhibited the expression of ICAM-1 and VCAM-1 on cell surface by 31% and 36% at 30 µ mol/L. L-THP pretreatment could also markedly reduce transcriptional and translational level of VCAM-1 as well as mildly reduce the total protein and mRNA expression levels of ICAM-1. Furthermore, I-THP attenuated TNF-α-stimulated NF-κ B nuclear translocation. CONCLUSION: These results provide evidences supporting that I-THP could be a promising compound in the prevention and treatment of the early vascular inflammatory reaction in atherosclerosis by inhibiting monocyte adhesion to vascular endothelial cell through downregulating ICAM-1 and VCAM-1 in vascular endothelial cell based on suppressing NF-κ B.


Assuntos
Alcaloides de Berberina/farmacologia , Regulação para Baixo/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/citologia , Molécula 1 de Adesão Intercelular/metabolismo , Monócitos/citologia , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Molécula 1 de Adesão de Célula Vascular/metabolismo , Adesão Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/genética , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Transporte Proteico/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição RelA/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética
7.
Zhongguo Zhong Yao Za Zhi ; 39(2): 316-21, 2014 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-24761653

RESUMO

Sailuotong (SLT) is a compound preparation composed of ginseng, ginkgo and saffron for the treatment of vascular dementia In order to identify its material foundation and provide evidence for therapeutic regimen, the pharmacokinetics and brain distribution of ginsenosides were investigated after intragastric administration of SLT. An LC-MS/MS method was developed for the determination of 7 ginsenosides in rat plasma simultaneously. Statistical analysis of obtained data demonstrated that the method has achieved the desired linearity, precision, accuracy and sensitivity. After administration of SLT at 60 mg x kg(-1) dose, 7 ginsengosides were all absorbed into systematic circulation. The quantitative and statistical analysis of gensenosides in plasma showed that protopanaxdiol saponins exhibited higher concentration and longer half life than protopanaxatriol saponins. The mean value of half life of ginsenosides Rg1, Re, Rb1, Rb2/b3, Rc and Rd were 15.26, 2.46, 18.41, 27.70, 21.86 and 61.58 h respectively. The peak concentration of them were 7.15, 2.83, 55.32, 30.22, 21.42, 8.81 microg x L(-1) respectively. The determination of brain distribution at different time after dosing revealed ginsenosides entered into brain promptly but the concentration declined along with time rapidly. The ginsenosides with higher concentration in brain were Rg1, Re, Rb1 and Rc. These findings demonstrated ginsenosides could be absorbed in blood and penetrated into brain rapidly. Some ginsenosides, especially Rg1 and Re, might be the main components directly effecting neurocyte in brain taking advantage of their better brain distribution. While ginsenosides of mostly protopanaxdiol saponins might protect brain mainly depending on peripheral efficacy in virtue of their long residence in blood, by which higher concentration could be reached after multiple dosing.


Assuntos
Encéfalo/metabolismo , Medicamentos de Ervas Chinesas/administração & dosagem , Ginsenosídeos/farmacocinética , Animais , Masculino , Ratos , Ratos Wistar , Fatores de Tempo
8.
Zhongguo Zhong Yao Za Zhi ; 38(23): 4138-43, 2013 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-24791505

RESUMO

OBJECTIVE: To discuss that pathogenesis evolvement regularity of Chinese miniature swine with phlege-stasis cementation syndrome of coronary heart disease. METHOD: Eighteen Chinese miniature swine were randomly divided to the normal control group, the model group and the Danlou tablet group, with six swine in each group. Except for the normal control group, all of the other groups were fed with high fat diet for two weeks. The coronary heart disease model with phlegm-stasis cementation syndrome was established by injuring left anterior descending artery with interventional balloons and continuously feeding with high fat diet for eight weeks. The levels of BMI, hemorheological parameters, lipids in serum and inflammatory cytokines were observed at the 0th (before the experiment), 2nd (before operation or drug administration), 6th (four weeks after drug administration) and 10th week (eight weeks after drug administration) of study. The levels of TG and TC in liver and the pathological changes in coronary artery tissues were also observed at the end of study. RESULT: Compared with the normal control group, the model group had showed significant increase in the levels of TC, TG, LDL-C and VLDL-C in serum (P < 0.01) from the second week to the end of the experiment, with notable rise in the whole blood viscosity under the shear rates of 5 s(-1) and 60 s(-1). At the 6th week, the levels of BMI and TG and TNF-alpha in serum significantly increased. At the 10th week, the levels of BMI and hs-CRP, IL-6 and TNF-alpha in serum significantly increased as well, with remarkable increase in coronary stenosis, intimal thickness and the ratio between intimal thickness and media thickness (P < 0.05 and P < 0.01), and significant rise in TC and TG in livers (P < 0.01). Compared with the model group, the Danlou tablet group showed obvious reduction in severity of coronary artery lesion, intimal thickness and lumen stenosis ratio and ratio between intimal thickness and media thickness (P < 0.01), BMI, TC, TG, LDL-C and VLDL-C in serum, TC and TG in liver, as well as hs-CRP, IL-6 and TNF-alpha levels in serum (P < 0.05 and P < 0.01), with notable decline in the whole blood viscosity under the shear rates of 5 s(-1) and 60 s(-1). CONCLUSION: The interaction of phlegm, blood stasis and toxin syndromes helps promote the progress and development of AS plaques, which is the key pathogenesis of phlegm-stasis cementation syndrome in coronary heart disease.


Assuntos
Doença das Coronárias/sangue , Doença das Coronárias/fisiopatologia , Hemodinâmica , Medicina Tradicional Chinesa , Porco Miniatura , Animais , Peso Corporal , Feminino , Mediadores da Inflamação/metabolismo , Lipídeos/sangue , Fígado/metabolismo , Masculino , Suínos
9.
Zhongguo Zhong Yao Za Zhi ; 38(24): 4357-61, 2013 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-24791545

RESUMO

OBJECTIVE: To establish the "clinical-mimetic" Chinese medicine symptom complex score method for the coronary heart disease Chinese miniature swine model with phlegm-stasis cementation syndrome, in order to observe the effect of formula of removing both phlegm and blood stasis (TYTZ) on the Chinese medicine symptom complex score for the coronary heart disease Chinese miniature swine model with phlegm-stasis cementation syndrome. METHOD: Totally 36 Chinese miniature swine were randomly divided to the normal control group, the model group, the Shujiangzhi group, and TYTZ groups with doses of 2.0, 1.0 and 0.5 g x kg(-1), with six in each group. Except for the normal control group, all of the other groups were fed with high fat diet for two weeks. The coronary heart disease model with phlegm-stasis cementation syndrome was established by injuring left anterior descending artery with interventional balloons and continuously feeding with high fat diet for eight weeks. After the operation, the groups were administered with drugs for eight weeks. Their main symptoms, accompanied symptoms, tongue and pulse signs of the coronary heart disease Chinese miniature swine with phlengm-stasis cementation syndrome were observed according to the symptom-graded scoring method. RESULT: Compared with the model group, TYTZ in different doses could reduce the scores of main symptoms at the 6th and 10th week. Specifically, TYTZ in low dose could reduce the scores of tongue at the 6th week and the scores of accompanied symptoms, and tongue and pulse signs at the 10th week; And TYTZ in high dose could decrease all symptom scores at the 6th and 10th week (P < 0.05 or P < 0.01). CONCLUSION: TYTZ can improve the scores of the main symptoms, accompanied symptoms, tongue and pulse signs in coronary heart disease Chinese miniature swine with phlegm-stasis cementation syndrome. It is suggested that the "clinical-mimetic" objective scoring for syndromes of Chinese miniature swine is of great significant to the development of new traditional Chinese medicine drugs.


Assuntos
Doença das Coronárias/sangue , Doença das Coronárias/fisiopatologia , Medicina Tradicional Chinesa/métodos , Porco Miniatura , Animais , Química Farmacêutica , Doença das Coronárias/diagnóstico , Doença das Coronárias/terapia , Feminino , Masculino , Suínos
10.
Breast J ; 17(6): 657-60, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21933300

RESUMO

We performed a retrospective study of 856 breast cancer patients in our hospital, to compare the therapeutic effect of pirarubicin with cyclophosphamide and 5-fluorouracil (CPF) with the standard epirubicin-based regimen (CEF) in adjuvant treatment of breast cancer. Patients were given cyclophosphamide and 5-fluorouracil 500 mg/m(2) each, and either pirarubicin 40 mg/m(2) or epirubicin 75-100 mg/m(2) , every 3 weeks, six cycles. A total of 233 patients used CPF and 623 patients used CEF regimen. The clinical and pathologic characteristics were well balanced between the two groups. The median follow-up time was 41 months, relapse-free survival (RFS) and overall survival (OS) were similar in both groups, p = 0.561 and p = 0.783, respectively. No treatment-related congestive heart failure or death was observed in either group. Regardless of chemotherapy regimens, only tumor size, lymph node status, and ER status were predictive factors in multivariate survival analysis. In stratified analysis, the total hazard ratio estimate for RFS was 0.876 (95% CI 0.561-1.369; p = 0.562), not in favor of either regimen, and no significant difference was observed in any subgroups between the two treatment arms. Our study verified that 3 weekly CPF gives the same efficacy and safety as the standard CEF; both CPF and CEF are the effective regimens that can be used in adjuvant chemotherapy of breast cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Neoplasias da Mama/mortalidade , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Epirubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
J Chromatogr A ; 1134(1-2): 194-200, 2006 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-17046776

RESUMO

Theophylline imprinted monolithic columns were designed and prepared for rapid separation of a homologous series of xanthine derivatives, caffeine, and theophylline by an in situ thermal-initiated copolymerization technique. Caffeine and theophylline were fully separated both under isocratic and gradient elutions on this kind of monolithic molecularly imprinted polymers (MIP) column. The broad peak showed in isocratic elution could be improved in gradient elution. Some chromatographic conditions such as mobile phase composition, flow rate, and the temperature on the retention times were investigated. Hydrogen bonding interaction and hydrophobic interaction played an important role in the retention and separation. The binding capacity was evaluated by static adsorption and Scatchard analysis, which showed that the dissociation constant (KD) and the maximum binding capacity (Qmax) were 1.50 mol/L, and 236 micromol/g for high affinity binding site, and 7.97 mol/L and 785 micromol/g for lower affinity binding site, respectively. Thermodynamic data (DeltaDeltaH and DeltaDeltaS) obtained by Van't Hoff plots revealed an enthalpy-controlled separation. The morphological characteristics of monolithic MIP were investigated by scanning electron microscope, which showed that both mesopores and macropores were formed in the monolith. The present monolithic MIP column was successfully applied for the quantitative determination of caffeine and theophylline in different kinds of green tea.


Assuntos
Cafeína/análise , Chá/química , Teofilina/análise , Adsorção , Cafeína/química , Cafeína/isolamento & purificação , Polímeros , Temperatura , Teofilina/química , Teofilina/isolamento & purificação , Termodinâmica
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