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1.
Nurse Educ Today ; 129: 105894, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37467708

RESUMO

BACKGROUND: Currently, a paramount issue in nursing education is to motivate nursing undergraduate interns to develop self-directed learning skills and improve their practice satisfaction and professional identity, so as to meet the growing demands in healthcare. OBJECTIVES: This study aimed to examine the effectiveness of a motivational programme based on the Existence-Relatedness-Growth (ERG) theory in developing self-directed learning skills, improving practice satisfaction and promoting the professional identity of nursing undergraduate interns in China. DESIGN: A quasi-experimental study design. SETTING: A government-funded tertiary teaching hospital in Guangzhou, Guangdong province, China. METHODS: This study was conducted with 99 nursing undergraduate interns in a hospital between June 2020 and April 2022. The interns in the experimental group (n = 50) participated in the motivational programme based on ERG theory, while those in the control group (n = 49) underwent a traditional training programme. The interns in the two groups were compared in terms of their degree of self-directed learning, practice satisfaction and professional identity after the training, using independent samples t-test. RESULTS: After the internship, interns in the experimental group showed a statistically significantly higher level of self-directed learning and practice satisfaction than those in the control group (p < 0.05). However, no significant difference was observed in professional identity between the two groups after the internship. CONCLUSIONS: The motivational programme based on ERG theory was shown to be effective in improving self-directed learning and practice satisfaction in nursing undergraduate interns. A large-scale randomized controlled trial is warranted to confirm the results.


Assuntos
Educação em Enfermagem , Internato e Residência , Estudantes de Enfermagem , Humanos , Aprendizagem , Atenção à Saúde
2.
J Pharm Biomed Anal ; 224: 115191, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36512868

RESUMO

In this study, we investigated the effect of type 1 diabetes mellitus on the modulation of the activities of CYP450s in dynamics by a UHPLC-MS/MS method. The diabetic rat model was constructed by an intraperitoneal single injection of streptozotocin. Fasting blood glucose levels > 16.7 mmol/L were considered as diabetic. The rats were given a cocktail of four probe drugs (10 mg/kg phenacetin, 1 mg/kg tolbutamide, 10 mg/kg metoprolol, and 10 mg/kg midazolam) by oral administration for the pharmacokinetic study. Thereafter, the metabolic ratio (MR) of the metabolites to probe substrates were determined. The results indicated that two weeks after diabetes was induced, diabetes increased the MRs of acetaminophen/phenacetin (CYP1A2) and 4-hydroxyl tolbutamide/tolbutamide (CYP2C9); however, it decreased the MRs of α-hydroxy metoprolol/metoprolol (CYP2D6) and 1-hydroxy midazolam/midazolam (CYP3A4). Two months after diabetes was induced, diabetes increased the MRs of acetaminophen/phenacetin and 4-hydroxyl tolbutamide/tolbutamide. The MR of α-hydroxy metoprolol/metoprolol was decreased and the MR of 1-hydroxy midazolam/midazolam was increased but the difference was not significant. According to the results, CYP1A2 and CYP2C9 activities were enhanced in the diabetic rats. and CYP2D6 activity was inhibited in a short period of diabetes; however, the decrease in CYP2D6 activity was not significant in the long period. CYP3A4 activity was decreased in a short period of diabetes and increased in a long period of diabetes but was not significant in the two periods. This study suggests the activity change rule of the CYP450 enzyme system in diabetes mellitus, which can provide a reference for precise clinical medication.


Assuntos
Citocromo P-450 CYP1A2 , Diabetes Mellitus Experimental , Animais , Ratos , Acetaminofen , Cromatografia Líquida de Alta Pressão/métodos , Citocromo P-450 CYP2C9 , Citocromo P-450 CYP2D6 , Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Metoprolol , Midazolam/metabolismo , Fenacetina , Espectrometria de Massas em Tandem/métodos , Tolbutamida
3.
Sci Rep ; 11(1): 3366, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33564010

RESUMO

In the present work, Ag@AgCl-reinforced cellulose composites with enhanced antibacterial and photocatalytic degradation properties were successfully synthesized via oil bath heating method. During the process, zinc chloride (ZnCl2) solution was used as both Cl- resource to form AgCl and the solvent to dissolve cellulose. The samples were synthesized with different temperatures, times, and concentrations of ZnCl2 solution. The morphology, microstructure and phase of the as-prepared samples were analyzed with X-ray powder diffraction (XRD), fourier transform infrared (FTIR) spectrometry, scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy (XPS), photocatalytic activity studies and inhibition zone experiments. Results showed that dye solution could be completely degraded by the materials in 1 h, and higher concentrations of ZnCl2 solution favored for larger inhibition zones (higher to 10.8 mm). This synthetic strategy displayed here offers more possibilities to high value-added applications of cellulose.

4.
Carbohydr Polym ; 253: 117170, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33278964

RESUMO

Microwave-assisted hydrolysis has been widely studied for cellulose fiber isolation, but the influence of reaction conditions and the microwave non-thermal effect are not well clarified. In this study, a series of well-designed experiments were carried out to measure the effects of reaction conditions including temperature, duration and alkali concentration. Compared to the other parameters, temperature was more relevant to the cellulose content in fiber. It could reach the maximum purity of 90.66 % when the temperature was up to 140 °C. Moreover, the existence of non-thermal effect of microwave has been confirmed through extensive determination and characterization of the fibers obtained from parallel controlled experiments conducted with or without microwave assistance. Approximately 50 %-75 % reduction in reaction time or 67 % of that in chemical costs would be realized under microwave with respect to traditional heating hydrolysis. Therefore, this work provides both deep insight and efficiency strategy into the microwave-assisted cellulose isolation.

5.
J Anal Methods Chem ; 2019: 5016757, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31886022

RESUMO

Anlotinib is a novel inhibitor of receptor kinase tyrosine with multitargets and has a broad spectrum of inhibitory action on tumor angiogenesis and growth. A simple and rapid UHPLC-MS/MS bioanalytical method was validated for the determination of anlotinib in rat plasma, using imatinib as an internal standard. An Acquity BEH C18 column was used to separate analytes. The eluents consisted of formic acid/water (0.1 : 100, v/v) and acetonitrile with a mobile phase. A triple quadrupole mass spectrometer was operated for the quantification with multiple reaction monitoring (MRM) to determine transitions: 408.2 ⟶ 339.1 for anlotinib, and 494.3 ⟶ 394.1 for imatinib. The validated range was 0.1-50 ng/mL for anlotinib. Mean recovery rate of anlotinib in plasma was ≥99.32% and reproducible. Also, the intra- and interday precisions were both below 15%. This robust method was successfully applied to support the pharmacokinetic study of anlotinib in rats.

7.
Ultrason Sonochem ; 24: 27-35, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25499465

RESUMO

Understanding the mechanism of ultrasound from metal hydroxide to oxides via an ultrasound irradiation method is of great importance for broadening and improving their synthesis and industrial applications. The purpose of this article was to explore the mechanism of ultrasound on the synthesis of cellulose/Cu(OH)2/CuO hybrids. The influences of various reaction parameters including the volume of H2O2, heating method, pulse mode of ultrasound irradiation, sonication time, and power density on the cellulose/Cu(OH)2/CuO hybrids were investigated in detail by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectra (EDS), thermogravimetric analysis (TGA), and derivative thermogravimetry (DTG). The experimental results indicated that all the parameters have effects on the cellulose/Cu(OH)2/CuO hybrids, power density had an effect on the phase transformation of Cu(OH)2 to CuO, and the addition of H2O2 played an important role in the shape of cellulose hybrids, which provided an indirect evidence on the H2O2-induced oxidation route for the transformation process from Cu(OH)2 to CuO during the ultrasound irradiation process. These results maybe direct the synthesis and potential applications of cellulose hybrids in the near future.

8.
PLoS One ; 9(6): e99089, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24897112

RESUMO

BACKGROUND: Confocal laser endomicroscopy (CLE) can provide in vivo subcellular resolution images of esophageal lesions. However, the learning curve in interpreting CLE images of precancerous or early-stage esophageal squamous cancer is unknown. The goal of this study is to evaluate the diagnostic accuracy and inter-observer agreement for differentiating esophageal lesions in CLE images among experienced and inexperienced observers and to assess the learning curve. METHOD: After a short training, 8 experienced and 14 inexperienced endoscopists evaluated in sequence 4 sets of high-quality CLE images. Their diagnoses were corrected and discussed after each set. For each image, the diagnostic results, confidence in diagnosis, quality and time to evaluate were recorded. RESULTS: Overall, diagnostic accuracy was greater for the second, third, fourth set of images as compared with the initial set (odds ratio [OR] 2.01, 95% CI 1.22-3.31; 7.95, 3.74-16.87; and 6.45, 3.14-13.27), respectively, with no difference between the third and fourth sets in accuracy (p = 0.67). Previous experience affected the diagnostic accuracy only in the first set of images (OR 3.70, 1.87-7.29, p<0.001). Inter-observer agreement was higher for experienced than inexperienced endoscopists (0.732 vs. 0.666, p<0.01). CONCLUSION: CLE is a promising technology that can be quickly learned after a short training period; previous experience is associated with diagnostic accuracy only at the initial stage of learning.


Assuntos
Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Esofagoscopia/métodos , Curva de Aprendizado , Microscopia Confocal/métodos , Variações Dependentes do Observador , Lesões Pré-Cancerosas/patologia , Humanos , Lasers , Prognóstico
9.
Carbohydr Polym ; 106: 14-21, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24721045

RESUMO

The primary objective of this work was to evaluate the effect of reducing reagents on the hybrids from cellulose and Ag, which have been successfully synthesized by using fructose and glucose as reducing reagents via a hydrothermal method, respectively. The hybrids were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential thermal analysis (DTA). The influences of the various reaction parameters including the heating time, heating temperature, and types of reducing reagents on the hybrids were investigated. Silver particles can be better dispersed in the cellulose matrix by adjusting reaction parameters. Experimental results demonstrated that the types of reducing reagents played an important role in the shape and dispersion of silver particles in hybrids.


Assuntos
Celulose/química , Frutose/farmacologia , Glucose/farmacologia , Substâncias Redutoras/farmacologia , Prata/química , Microscopia Eletrônica de Varredura , Temperatura , Difração de Raios X
10.
Carbohydr Polym ; 102: 445-52, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24507304

RESUMO

The purpose of this study was to explore a green strategy about the high value-added applications of biomass. Hybrids from lignocelluloses and silver have been successfully prepared using NaBH4 as reducing reagent by an environmentally-friendly sonochemistry method. The phase, microstructure, and morphology of the hybrids were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential thermal analysis (DTA). The influences of the various reaction parameters including reaction time, lignocelluloses concentration, and types of reducing reagents on the products were investigated in detail. Silver particles can be better dispersed on the lignocelluloses matrix by adjusting reaction parameters. These hybrids may be a promising antimicrobial material for their applications in the biomedical field. This environmentally-friendly synthetic strategy reported here opens a new window to the high value-added applications of lignocelluloses.


Assuntos
Lignina/síntese química , Prata/química , Lignina/química , Microscopia Eletrônica de Varredura , Difração de Pó , Termogravimetria
11.
Carbohydr Polym ; 99: 166-72, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24274493

RESUMO

This study aims to investigate the fabrication and property of cellulose/Ag/AgCl hybrids. In this article, preparation of cellulose/Ag/AgCl hybrids was reported using the cellulose solution, AgNO3, AlCl3·6H2O with ultrasound agitation method. The cellulose solution was synthesized by the dissolution of the microcrystalline cellulose in NaOH/urea aqueous solution. Influences of the experimental parameters of ultrasound treatment time and ultrasonic intermittent on the hybrids were investigated. The phase, microstructure, thermal stability, and morphology of the hybrids were characterized by X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectrometry, thermogravimetric analysis (TGA), differential thermal analysis (DTA), and scanning electron microscopy (SEM). Results showed the successful synthesis of cellulose/Ag/AgCl hybrids with good thermal stability. Moreover, the hybrids displayed desirable antimicrobial activities. Compared with other conventional methods, the rapid, green, and environmentally friendly ultrasound agitation method opens a new window to the high value-added applications of biomass.


Assuntos
Antibacterianos/síntese química , Celulose/química , Compostos de Prata/química , Cloreto de Alumínio , Compostos de Alumínio/química , Antibacterianos/farmacologia , Cloretos/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Química Verde , Nitrato de Prata/química , Hidróxido de Sódio/química , Sonicação , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Termogravimetria , Ureia/química , Difração de Raios X
12.
Carbohydr Polym ; 98(1): 168-73, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23987331

RESUMO

The purpose of this article was to explore an environmentally friendly strategy to synthesis of biomass-based hybrids. Herein, microwave-assisted ionic liquids method was applied to fabricate the hybrids from cellulose and AgX (X=Cl, Br) using cellulose and AgNO3. The ionic liquids act simultaneously as a solvent, a microwave absorber, and a reactant. Ionic liquids provided Cl(-) or Br(-) to the synthesis of AgCl or AgBr crystals; thus no additional reactant is needed. The products are characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectrometry (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential thermal analysis (DTA). The cellulose-Ag/AgCl hybrid and cellulose-Ag/AgBr hybrid were also obtained by using cellulose-AgCl and cellulose-AgBr hybrids as precursors. This environmentally friendly microwave-assisted ionic liquids method is beneficial to the hybrids with high dispersion.


Assuntos
Brometos/química , Celulose/química , Celulose/síntese química , Química Verde , Líquidos Iônicos/química , Micro-Ondas , Compostos de Prata/química , Técnicas de Química Sintética , Substâncias Redutoras/química
13.
Carbohydr Polym ; 96(1): 15-20, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23688449

RESUMO

The purpose of this study was to explore a new strategy to improve the high value-added applications of biomass. Hybrid from cellulose and titanium dioxide (TiO2) was successfully prepared by using tetra-n-butyl titanate and cellulose solution via a hydrothermal method at 180°C for 24h. The phase, microstructure, morphology, and thermal stability of the hybrid were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectrometry (FT-IR), thermogravimetric analysis (TGA), differential thermal analysis (DTA), and scanning electron microscopy (SEM). The influences of the tetra-n-butyl titanate concentration and the types of solvent on the products were investigated. The TiO2 nanoparticles were dispersed on the surface of cellulose and/or in the cellulose matrix. The hybrid possessed an antimicrobial activity against the model microbes Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive), and were a promising antimicrobial material for the applications in the biomedical field.


Assuntos
Antibacterianos/farmacologia , Celulose/farmacologia , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Titânio/farmacologia , Antibacterianos/química , Celulose/química , Cristalização , Difração de Pó , Termogravimetria , Titânio/química , Difração de Raios X
14.
Ultrason Sonochem ; 20(5): 1188-93, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23591018

RESUMO

Vaterite is an important biomedical material due to its features such as high specific surface area, high solubility, high dispersion, and small specific gravity. The purposes of this article were to explore the growth mechanism of vaterite on the cellulose matrix via sonochmistry process. In the work reported herein, the influences of experimental parameters on the polymorph of calcium carbonate were investigated in detail. The calcium carbonate crystals on the cellulose matrix were characterized by means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Experimental results revealed that all the reactants, solvent, and synthesis method played an important role in the polymorph of calcium carbonate. The pure phase of vaterite polymorph was obtained using Na2CO3 as reactant in ethylene glycol on the cellulose matrix via sonochmistry process. Based on the experimental results, one can conclude that the synthesis of vaterite polymorph is a system process.


Assuntos
Carbonato de Cálcio/química , Carbonato de Cálcio/síntese química , Celulose/química , Sonicação , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
16.
Carbohydr Polym ; 92(2): 1669-76, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23399205

RESUMO

The purposes of this article are to synthesize the biomass-based hybrid nanocomposites using green method in green solvent and evaluate its biological activity. In this paper, microwave-assisted ionic liquid method is applied to the preparation of cellulose/CaCO(3) hybrid nanocomposites in the alkali extraction cellulose using CaCl(2) and Na(2)CO(3) as starting reactants. The ionic liquid acts as the excellent solvent for absorbing microwave and the dissolution of cellulose, and the synthesis of cellulose/CaCO(3) nanocomposites. The influences of reaction parameters such as the cellulose concentration and the types of solvent on the products were investigated. The increasing cellulose concentration favored the growth of CaCO(3). The morphologies of CaCO(3) changed from polyhedral to cube to particle with increasing cellulose concentration. Moreover, the solvents had an effect on the shape and dispersion of CaCO(3). Cytotoxicity experiments demonstrated that the cellulose/CaCO(3) nanocomposites had good biocompatibility and could be a candidate for the biomedical applications.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/síntese química , Carbonato de Cálcio/química , Celulose/química , Líquidos Iônicos/química , Micro-Ondas , Nanocompostos/química , Materiais Biocompatíveis/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Química Sintética , Química Verde , Humanos , Nanocompostos/toxicidade , Solventes/química
17.
PLoS One ; 8(1): e54183, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23349820

RESUMO

BACKGROUND: Functional gastrointestinal disorders, including functional dyspepsia, irritable bowel syndrome and functional constipation are very common worldwide. OBJECTIVE: This research aims to estimate the prevalence and associated factors involved in functional gastrointestinal disorders in Chinese college and university students using the Rome III criteria. METHODS: A total of 5000 students from Shandong University in China were asked in January-May 2012 to complete questionnaires, including the Rome III questionnaire, hospital anxiety and depression scale, and negative life events scale. RESULTS: Based on the 4638 students who completed the questionnaire, the prevalence of functional dyspepsia, irritable bowel syndrome and functional constipation in college and university students of North China worked out to be 9.25%, 8.34% and 5.45% respectively. They were more frequent in female students. The factors of anxiety (OR 1.07; 95% CI 0.99 to 1.16, P=0.002<0.05) and depression (OR 0.55; 95% CI 0.15 to 1.05, P=0.045<0.05) indicated a high risk of causing irritable bowel syndrome. CONCLUSION: Functional dyspepsia, irritable bowel syndrome and functional constipation were common in college and university students of North China. Psychological disorders such as anxiety and depression provide significant risk factors for irritable bowel syndrome patients.


Assuntos
Gastroenteropatias/epidemiologia , Estudantes/estatística & dados numéricos , Inquéritos e Questionários , Universidades , Ansiedade/epidemiologia , Povo Asiático/estatística & dados numéricos , China/epidemiologia , Comorbidade , Constipação Intestinal/epidemiologia , Depressão/epidemiologia , Dispepsia/epidemiologia , Feminino , Gastroenteropatias/diagnóstico , Gastroenteropatias/psicologia , Humanos , Síndrome do Intestino Irritável/epidemiologia , Modelos Logísticos , Masculino , Prevalência , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Estudantes/psicologia , Adulto Jovem
18.
Gut ; 62(11): 1547-55, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22936670

RESUMO

OBJECTIVE: Loss of surface maturation and cytonuclear atypia have been regarded as the pathological 'gold standard' for the diagnosis of oesophageal squamous cell intraepithelial neoplasia. However, there has been no satisfactory endomicroscopic method similar to this pathological approach to detect surface maturation and screen for oesophageal squamous cell intraepithelial neoplasia. The aim of this study was to apply a 3-dimensional (3D) confocal endomicroscopic imaging technique to investigate the surface maturation of the oesophageal epithelium and develop new 2-dimensional confocal endomicroscopic criteria based on surface maturation. DESIGN: In the 3D reconstruction phase, intrapapillary capillary loops were reconstructed to demonstrate the stereo configuration of the oesophageal epithelium, and a novel surface maturation scoring (SMS) method for plane confocal images was developed based on the interpretation of the 3D microstructure. In the SMS diagnostic phase, 1214 patients were screened and confocal images from 64 non-invasive oesophageal lesions were independently evaluated using SMS and previous methods. RESULTS: We successfully obtained and interpreted 3D confocal images of the human oesophageal epithelium for the first time. The sensitivity (81.0%, 95% CI 58.1% to 94.6%) and specificity (90.7%, 95% CI 77.9% to 97.4%) of the newly established SMS were superior to previous confocal approaches in distinguishing squamous intraepithelial neoplasia from other non-invasive lesions. CONCLUSIONS: 3D confocal endomicroscopic imaging provides valuable insight into the stereo configuration of the human oesophageal epithelium. SMS is a novel and promising diagnostic method to distinguish neoplasia during ongoing endoscopy.


Assuntos
Carcinoma in Situ/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Neoplasias Esofágicas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Carcinoma in Situ/patologia , Carcinoma de Células Escamosas/patologia , Detecção Precoce de Câncer/métodos , Neoplasias Esofágicas/patologia , Esofagoscopia/métodos , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Masculino , Microscopia Confocal/métodos , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Prospectivos , Sensibilidade e Especificidade , Adulto Jovem
19.
Ultrason Sonochem ; 20(3): 839-45, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23200085

RESUMO

The purposes of this article were to investigate the influences of synthesis strategy on the CaCO(3) crystals on the cellulose substrate. In this study, CaCO(3) crystals were synthesized using cellulose as matrix by the microwave-assisted method and ultrasound agitation method, respectively. The CaCO(3) crystals on the cellulose substrate were characterized by means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Experimental results demonstrated that the synthesis strategy had a dramatically influences on the phase, microstructure, morphology, thermal stability, and biological activity of the CaCO(3) crystals. The pure phase of vaterite spheres with the diameter of about 320-600nm were obtained by ultrasound agitation method, meanwhile, the mixed phases of calcite and vaterite with the diameter of about 0.82-1.24µm were observed by microwave-assisted method. In view of experimental results, one can conclude that the ultrasound agitation method do more favors to the synthesis of CaCO(3) crystals with uniform morphology and size, compared with microwave-assisted method. Furthermore, cytotoxicity experiments indicated that the CaCO(3) crystals on the cellulose substrate had good biocompatibility and could be a candidate for the biomedical applications.


Assuntos
Materiais Biocompatíveis/química , Carbonato de Cálcio/química , Celulose/química , Micro-Ondas , Sonicação/métodos , Materiais Biocompatíveis/toxicidade , Carbonato de Cálcio/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Celulose/toxicidade , Cristalização , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Propriedades de Superfície , Difração de Raios X
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