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1.
Lupus ; 33(4): 387-396, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38305218

RESUMO

BACKGROUND: Systemic lupus erythematosus (SLE) is a chronic, multisystem autoimmune disorder. When SLE occurs in individuals under the age of 18, it is referred to as childhood-onset SLE (cSLE). Currently, there is a dearth of bibliometric research pertaining to cSLE. METHOD: Relevant studies in the field of cSLE from 2000 to 2022 were screened from the Web of Science Core Collection (WoSCC). CiteSpace and VOSviewer software were used to visualize the annual publications, countries, institutions, authors, journals, keywords, and references, after which the authors conducted the scientific analysis. RESULTS: A total of 2857 articles were included in this study, and the number of articles published in the past 20 years showed an overall upwards trend. The most prolific countries are the United States, China, and Brazil; however, the United States, Canada, and the United Kingdom are clearly superior in terms of literary influence, and there is more cooperation between them and their institutions. LUPUS (n = 389) contributed the most to the variance. Brunner, HI's contribution in the field of cSLE is outstanding. The words related to 'lupus nephritis' and 'antibodies' are important words reflected in the keyword network diagram. The keywords included 'evidence-based recommendation', 'validation', 'diagnosis' and 'adult' from 2019, and 'continuous bursts' to the present. CONCLUSION: This study examined the research status of cSLE patients, discussed and analysed the research hotspots and trends in this field, and provided a reference for further research in this field to promote the development of cSLE research.


Assuntos
Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico , Anticorpos , Bibliometria , Brasil
2.
Rheumatol Int ; 43(6): 1121-1133, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36167928

RESUMO

Idiopathic inflammatory myopathy is a multisystem autoimmune condition characterized by muscle inflammation (myositis) and interstitial lung disease (ILD). Bibliometric analysis and altmetric analysis are effective methods of evaluating academic productivity and measuring the influence of publications. The purpose of this study is to analyze the research productivity and influence of idiopathic inflammatory myopathy articles using bibliometric analysis and altmetric analysis. Data from articles published between 2011 and 2021 were obtained from the Web of Science. Altmetric attention scores and Mendeley reader counts of the articles were obtained from altmetric evaluations. In the study, 2060 articles related to idiopathic inflammatory myopathy were screened out showing an increasing trend in general. In terms of the origin countries of articles, the United States (n = 467, 22.67%) ranked first. Johns Hopkins University has the largest number of institutions (n = 113). The journals regarding idiopathic inflammatory myopathy and Rheumatology (n = 87) published the most articles. The most cited article was published by Mammen et al. and was related to autoantibodies. Dermatomyositis, polymyositis and other research hotspots were represented by keywords. The results of the altmetric analysis showed that citations, impact factors and h-index were significantly correlated with Altmetric Attention Scores and Mendeley Readers Count (P < 0.05). In summary, bibliometric analysis summarizes the current status of idiopathic inflammatory myopathy research and helps to understand the development of idiopathic inflammatory myopathy in the field between 2011 and 2021. Altmetric analysis was used to evaluate the academic and social influence of articles from the novel perspective of internet attention.


Assuntos
Miosite , Mídias Sociais , Humanos , Fator de Impacto de Revistas , Bibliometria , Internet
3.
J Sep Sci ; 43(9-10): 1634-1652, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32043724

RESUMO

Sulfonamides in environmental water, food, and feed are a major concern for both aquatic ecosystems and public health, because they may lead to the health risk of drug resistance. Thus, numerous sensitive detection and rapid removal methodologies have been established. This review summarizes the sample preparation techniques and instrumental methods used for sensitive detection of sulfonamides. Additionally, adsorption and photocatalysis for the rapid removal of sulfonamides are also discussed. This review provides a comprehensive perspective on future sulfonamide analyses that have good performance, and on the basic methods for the rapid removal of sulfonamides.


Assuntos
Monitoramento Ambiental , Análise de Alimentos , Contaminação de Alimentos/análise , Sulfonamidas/análise , Poluentes Químicos da Água/análise
4.
Biosens Bioelectron ; 260: 116430, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38815465

RESUMO

Sweat contains abundant physiological and metabolic data to evaluate an individual's physical health. Since the non-exercise sweat secretion rate is low, with an average value of 1-10 µl h-1 cm-2, sweat is generally collected during exercise for existing wearable sweat sensors. To expand their applications to include daily scenarios, these sensors developed for sports and fitness are challenged by the difficulty of collecting trace amounts of sweat. This study proposes a wearable patch inspired by the hierarchical structure of Sarracenia trichomes, allowing for the spontaneous and fast collection of a small amount of secreted sweat. The patch contains microfluidic channels featuring a 20 µm-wide rib structure, fully utilizing the capillary force, thereby eliminating the issue of sweat hysteresis. Furthermore, with only 0.5 µl of the sweat secreted at the collection site, it can converge on the detection medium located within the center reservoir. Volunteer verification demonstrated a twofold increase in sweat collection efficiency compared to traditional wearable patches. This patch serves as an efficient sweat-collection configuration, promising potential for diverse in situ sweat colorimetric analyses.


Assuntos
Técnicas Biossensoriais , Desenho de Equipamento , Suor , Dispositivos Eletrônicos Vestíveis , Suor/química , Humanos , Técnicas Biossensoriais/instrumentação , Colorimetria/instrumentação
5.
Clin Rheumatol ; 43(1): 175-187, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37668951

RESUMO

BACKGROUND: Bibliometric analysis is a mature method for quantitative evaluation of academic productivity. In view of the rapid development of research in the field of systemic lupus erythematosus (SLE) in the past decade, we used bibliometric methods to comprehensively analyze the literature in the field of SLE from 2013 to 2022. METHODS: The relevant literature in the field of SLE from 2013 to 2022 was screened in the Web of Science Core Collection database. After obtaining and sorting out the data, CiteSpace and VOSviewer software were used to visualize the relevant data, and SPSS software was used for scientific statistics. RESULTS: A total of 18,450 publications were included in this study. The number of articles published over the past 10 years has generally shown an upward trend, while Altmetric attention scores have also shown a clear upward trend in general and in most countries. Citation analysis and Altmetric analysis can mutually prove and supplement the influence of papers. The USA, China, Japan, Italy, and the UK are the most productive countries, but China and Japan are significantly inferior to other countries in terms of research influence. Four of the top ten authors are at the center of the collaboration network. LUPUS is the most contributing journal. The theme of systemic lupus erythematosus research mainly focuses on the pathogenesis, treatment, and management of SLE, and the emerging trend is related research on machine learning and immune cells. CONCLUSION: This study shows the research status of SLE, clarifies the main contributors in this field, discusses and analyzes the research hotspots and trends in this field, and provides reference for further research in this field to promote the development of SLE research. Key Points • Through bibliometric analysis, Altmetric analysis, and visual analysis, we reveal the global productivity characteristics of SLE-related papers in the past 10 years. • The number of global SLE-related studies has shown a significant increase, indicating that SLE is still a hot topic and deserves further study. • Citation analysis and Altmetric analysis can mutually prove and supplement the influence of papers, and the attention of related literature among non-professional researchers is increasing. • The theme of SLE research mainly focuses on the pathogenesis, treatment, and management of SLE. The emerging trend is machine learning and immune cells, which may provide new strategies for the diagnosis and treatment of SLE in the future.


Assuntos
Bibliometria , Lúpus Eritematoso Sistêmico , Humanos , China , Bases de Dados Factuais , Suplementos Nutricionais
6.
Int Immunopharmacol ; 138: 112565, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38941669

RESUMO

OBJECTIVE: Rheumatoid arthritis (RA) is a chronic systemic disease characterized by inflammatory synovitis, and genetic factors play the greatest role in RA. This study aimed to investigate the relationship between Toll-like receptor 10(TLR10) gene polymorphisms and susceptibility to RA. METHODS: A total of 271 patients with RA and an equal number of healthy controls were included, and the TLR10 rs2101521, rs10004195 and rs11725309 loci were genotyped by time-of-flight mass spectrometry. RESULTS: Compared with healthy controls, Individuals carrying the rs2101521 G allele had an increased risk of developing RA (P = 0.01; odds ratio (OR) = 1.367; 95 % confidence interval (CI): 1.076-1.736). Individuals with the rs2101521 GG genotype had a greater risk of RA (P = 0.01; OR = 1.816; 95 % CI: 1.161-2.984). Stratified analysis demonstrated a greater prevalence of positive anti-cyclic citrullinated peptide (CCP)antibody in patients carrying the rs2101521 G allele (P = 0.03). Additionally, patients with the rs11725309 CT genotype had elevated levels of C-reactive protein (CRP)(P = 0.007). CONCLUSION: In conclusion, TLR10 gene polymorphisms are associated with RA susceptibility.

7.
Front Public Health ; 11: 1108007, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36778547

RESUMO

Objective: To understand the availability and affordability of essential drugs in Wuhan since the implementation of the national essential medicine system, and to provide a basis for the subsequent formulation and improvement of related policies. Methods: Using the standard survey method jointly developed by the WHO and Health Action International (HAI), a sample of 50 essential drugs was selected to investigate and evaluate their availability and affordability in public medical and health institutions and social retail pharmacies in Wuhan, using six diseases with high clinical morbidity as the targets. Results: The availability of the original drug and the lowest-priced generic drug in public hospitals is 26.4 and 42.47% respectively, and that in retail pharmacies is 26.8 and 54.4% respectively. The median price ratio of the original drug and the lowest-priced generic drug is 28.71 and 2.23 respectively in public hospitals, and 29.24 and 3.59 respectively in retail pharmacies; In addition to individual drugs, such as omeprazole, others are affordable. The availability of essential drugs in public hospitals in Wuhan is lower than that in social retail pharmacies, and the availability of the lowest-priced generic drugs is much higher than that of original drugs. Conclusion: The availability of essential drugs in public hospitals in Wuhan is lower than that in social retail pharmacies, and the availability of the lowest-priced generic drugs is much higher than that of original drugs. The price of the original drug is much higher than the international reference price; The price of medicines in public hospitals is lower than that in retail pharmacies;the overall condition of affordability is good, but there is a big gap between the affordability levels of original drugs and generic drugs, and the affordability of original drugs is relatively poor. It is recommended to adjust the relevant policies according to the actual situation of Wuhan city itself, moderately ensure the supply of original drugs, improve the price transparency of retail pharmacies, and ensure that the basic drug needs of the public are met.


Assuntos
Medicamentos Essenciais , Medicamentos Genéricos , Acessibilidade aos Serviços de Saúde , Custos e Análise de Custo , Padrões de Referência , Organização Mundial da Saúde
8.
Sci Total Environ ; 870: 161840, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-36716883

RESUMO

The synergistic effect of high microporosity and abundant heteroatoms is important for improving the performance of biochar in various fields. However, it is still challenging to create enough micropores for biochar, while simultaneously retaining the heteroatoms from biomass. A series of biochar with variable microstructures was successfully prepared by carbonization and following ball milling on lotus pedicel (LP), watermelon rind (WR), and litchi rind (LR). The pore structures and heteroatoms of biochar were characterized in detail. Notably, high microporosity could be realized by the carbonization of LR, and further ball milling resulted in a higher microporous surface area (1323.4 m2·g-1) and richer oxygen. Furthermore, the obtained biochar was fabricated as solid phase microextraction (SPME) coatings with uniform morphologies and similar thicknesses to deeply investigate the relationships between the microstructures and extraction performance. The best performance was demonstrated by the LR800BM, with enrichment factors from 1780 to 155,217. Finally, it was coupled with gas chromatography-mass spectrometry (GC-MS) to develop an analytical method with a wide linear range (1-50,000 ng·L-1), low limits of detection (0.10-1.4 ng·L-1), good repeatability (0.83 %-7.5 %) and reproducibility (4.2 %-8.9 %). This work provides valuable insights into the structure-performance relationship of biochar, which is important for the design of high-performance biochar-based adsorbents and their applications in the environment.

9.
Sci Total Environ ; 867: 161169, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36581266

RESUMO

Due to the strict rules and restrictions on the utilization of bisphenol A (BPA) around the world, an emerging endocrine disrupting chemical, bisphenol S (BPS) has been widely utilized as a substitute and frequently detected in the environment, even in the human body. Although it has been widely studied in the aquatic systems, the fate and toxicological effect of BPS in soil invertebrates are poorly known. This study presented a comprehensive exploration into the attenuation, bioaccumulation, and physiological distribution of BPS in an ecologically significant soil invertebrate, as well as its subsequent ecotoxicological effect to earthworm for the first time. The E. fetida could promote the BPS attenuation in soil, with degradation rates of 92.8 ± 1.6 % and 98.6 ± 1.1 % at dosage of 1.0 mg/kg dry weight soil (DWS) and 0.1 mg/kg DWS, respectively. The bioaccumulation of BPS in the earthworm was up to 111.6 ± 6.0 mg/kg lipid and 12.9 ± 2.9 mg/kg lipid with the initial dosage of 1.0 mg/kg DWS and 0.1 mg/kg DWS, respectively. Furthermore, BPS could induce oxidative stress and the process of antioxidant defense in earthworm cells at relatively high dose (1.0 mg/kg DWS and 10.0 mg/kg DWS), suggesting potential risks of BPS to the soil environment. This study could contribute to a more in-depth understanding of the fate of BPS in soil-earthworm system, and indicate a necessity for better understanding the environmental fate and ecological risks of BPA substitutes in the future.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Humanos , Bioacumulação , Poluentes do Solo/análise , Solo , Lipídeos
10.
Front Plant Sci ; 14: 1144406, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37063184

RESUMO

Lobelia species, as rich source of the alkaloid lobeline which has been shown to have important biological activity, have been used in folk medicine throughout East Asia to treat various diseases. However, Lobelia is a complex and varied genus in East Asia and is thus difficult to identify. Genomic resources would aid identification, however the availability of such information is poor, preventing a clear understanding of their evolutionary history from being established. To close this gap in the available genomic data, in this study, 17 plastomes of East Asian lobelias were newly sequenced and assembled. Although the plastomes of Lobelia sect. Hypsela, L. sect. Speirema, and L. sect. Rhynchopetalum shared the gene structure, the inverted repeat (IR)/large single copy (LSC) boundaries, genome size, and the number of repeats were variable, indicating the non-conservative nature of plastome evolution within these sections. However, the genomes of the Lobelia sect. Delostemon and L. sect. Stenotium showed rearrangements, revealing that these two sections might have undergone different evolutionary histories. We assessed nine hotspot genes and 27-51 simple sequence repeat motifs, which will also serve as valuable DNA barcode regions in future population genetics studies and for the delineation of plant species. Our phylogenetic analysis resolved the evolutionary positions of the five sections in agreement with previous evolutionary trees based on morphological features. Although phylogenetic reconstruction of Lobelioideae based on the rpoC2 gene has rarely been performed, our results indicated that it contains a considerable amount of phylogenetic information and offers great promise for further phylogenetic analysis of Lobelioideae. Our site-specific model identified 173 sites under highly positive selections. The branch-site model exhibited 11 positive selection sites involving four genes in the East Asian branches. These four genes may play critical roles in the adaptation of East Asian taxa to diverse environments. Our study is the first to detect plastome organization, phylogenetic utility, and signatures of positive selection in the plastomes of East Asian lobelias, which will help to further advance taxonomic and evolutionary studies and the utilization of medicinal plant resources.

11.
Artif Cells Nanomed Biotechnol ; 51(1): 286-296, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37224191

RESUMO

The development of haemoglobin-based oxygen carrier (HBOC) is an excellent supplement to pre-hospital emergency blood transfusions. In this study, a new type of HBOC was prepared by using human cord haemoglobin (HCHb) and glutaraldehyde (GDA) and Bis(3,5-dibromosalicyl) fumarate (DBBF) to modify (DBBF-GDA-HCHb), the changes of physicochemical indexes during its preparation were evaluated, while a traditional type of GDA-HCHb was prepared, and the oxygen-carrying capacity of two type of HBOC was evaluated by a rat model of 135.0% exchange transfusion (ET). Eighteen SD male rats were selected, and were randomly divided into control group (5.0% albumin), DBBF-GDA-HCHb group and GDA-HCHb group. The 12 h survival rate of the C group was 16.67%, and the two HBOC groups were both 83.33%. Compared with GDA-HCHb, DBBF-GDA-HCHb can reduce lactic acid content by supplying oxygen to hypoxic tissues in a more timely manner, and can also can improve the reduction of MAP due to ischaemia.


Assuntos
Substitutos Sanguíneos , Transfusão Total , Humanos , Masculino , Animais , Ratos , Polimerização , Substitutos Sanguíneos/farmacologia , Oxigênio , Cordão Umbilical , Eritrócitos
12.
Clin Rheumatol ; 42(5): 1285-1295, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36604357

RESUMO

BACKGROUND: Antiphospholipid syndrome is an autoimmune disorder characterized by recurrent vascular thrombosis and pregnancy losses in the presence of persistently positive antiphospholipid antibodies. Bibliometric analysis and altmetric analysis are methods of analyzing academic productivity and influence. Currently, the assessment of antiphospholipid syndrome through the above analyses is lacking. This study investigated the quantity and quality of studies in the field of antiphospholipid syndrome and revealed the characteristics of worldwide productivity on this disease by the bibliometric analysis and altmetric analysis. METHODS: The terms "APS," "antiphospholipid syndrome," "antiphospholipid-antibody syndrome," and "Hughes syndrome" were searched on the Web of Science Core Collection from January 1, 2011, to December 31, 2021. Original articles and reviews were selected. We set the filters as "English." RESULTS AND CONCLUSION: A total of 1818 articles were retrieved from 68 countries, of which 20 met the criteria of major active countries. High-income countries contributed 1341 articles (73.48%). The number of articles annually increased significantly in the 10-year period (P < 0.001). The USA (253, 13.91%) was the most productive country. Adjusted by population, Serbia was top of the list. According to the gross domestic product analysis, Serbia ranked first. The most used keywords such as thrombosis and antiphospholipid antibodies were presented by keywords analyses. A content analysis found antithrombotic and anticoagulant therapy as research hotspots. A significant correlation was detected between average citations and altmetric attention scores (P = 0.002) and Mendeley readers count (P < 0.001). From 2011 to 2021, the number of global articles increased rapidly. Most papers came from high-income countries. The relationship between the bibliometric and altmetric analyses were basically consistent; therefore the two can prove/complement each other. Key points • We revealed the global productivity characteristics of the papers related to antiphospholipid syndrome by using the methods of bibliometric analysis and altmetric analysis. • We found the most selected articles that describe the treatment of antiphospholipid syndrome, especially antithrombotic and anticoagulant treatments, which may be the current research hotspot.


Assuntos
Síndrome Antifosfolipídica , Bibliometria , Humanos , Anticorpos Antifosfolipídeos , Anticoagulantes , Fibrinolíticos , Trombose
13.
Front Oncol ; 13: 1186858, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074669

RESUMO

Background: Breast cancer (BC) is one of the females' most common malignant tumors there are large individual differences in its prognosis. We intended to uncover novel useful genetic biomarkers and a risk signature for BC to aid determining clinical strategies. Methods: A combined significance (p combined) was calculated for each gene by Fisher's method based on the RNA-seq, CNV, and DNA methylation data from TCGA-BRCA. Genes with a p combined< 0.01 were subjected to univariate cox and Lasso regression, whereby an RS signature was established. The predicted performance of the RS signature would be assessed in GSE7390 and GSE20685, and emphatically analyzed in triple-negative breast cancer (TNBC) patients, while the expression of immune checkpoints and drug sensitivity were also examined. GSE176078, a single-cell dataset, was used to validate the differences in cellular composition in tumors between TNBC patients with different RS. Results: The RS signature consisted of C15orf52, C1orf228, CEL, FUZ, PAK6, and SIRPG showed good performance. It could distinguish the prognosis of patients well, even stratified by disease stages or subtypes and also showed a stronger predictive ability than traditional clinical indicators. The down-regulated expressions of many immune checkpoints, while the decreased sensitivity of many antitumor drugs was observed in TNBC patients with higher RS. The overall cells and lymphocytes composition differed between patients with different RS, which could facilitate a more personalized treatment. Conclusion: The six genes RS signature established based on multi-omics data exhibited well performance in predicting the prognosis of BC patients, regardless of disease stages or subtypes. Contributing to a more personalized treatment, our signature might benefit the outcome of BC patients.

14.
Anal Chim Acta ; 1095: 109-117, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31864611

RESUMO

Integrating the steps of direct carbonization, removal of silica and polymerization of dopamine, four ordered mesoporous carbons (OMCs) doping with different constituents were prepared and characterized successfully, which were proved to possess similar ordered mesopore structure, high surface area and different hydrophilic properties. Subsequently, a series of pollutants were selected as target analytes to investigate the enrichment capacities of as-prepared OMCs based on the technique of solid phase microextraction (SPME). It was found that the OMC modified with polydopamine (OMC@PDA) demonstrated outstanding performance towards phenols, since its hydrophilicity was enhanced by PDA. Moreover, two extraction modes were employed to study the extraction process, including headspace and direct immersion. The synergistic enhancement effect of enrichment efficiency and mass transfer towards phenols using the OMC@PDA-coated fiber was demonstrated in the mode of direct immersion. To realize the target of high sensitivity, the OMC@PDA-coated fiber was coupled with the gas chromatography-mass spectrometry (GC-MS) after optimizations to develop analytical method. Wide linear range (5-5000 ng L-1), low detection limits (0.08-0.38 ng L-1) and excellent reproducibility made the developed method feasible for the determinations of trace phenols in environmental water samples.

15.
Anal Chim Acta ; 1070: 43-50, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31103166

RESUMO

Ordered mesoporous carbons (OMCs) are a kind of remarkable adsorbents in environment area due to high surface area, controllable pore size and superior stability. However, the inherent hydrophobicity and strong π-π interaction make OMCs have an advantage for the adsorption of nonpolar pollutants, leading to great demands for the development of new-type OMCs with outstanding adsorption efficiencies towards polar pollutants. The zirconium and nitrogen co-doped ordered mesoporous carbon (Zr/N-OMC) was obtained by directly carbonizing the composites of phenolic resin and UiO-66-NH2, with uniform mesopore structure, large surface area (583 m2 g-1) and widely dispersed heteroatoms. Due to these prominent properties, the Zr/N-OMC was fabricated as high-performance solid phase microextraction coating. The results proved that the doping zirconium and nitrogen could act as active sites to interact with polar pollutants, resulting in fast adsorption rate and enhanced adsorption capacity. Therefore, the high-performance Zr/N-OMC-coated fiber was coupled with gas chromatography-mass spectrometry to establish sensitive analytical method for the detection of trace phenols from real water samples. This work would open up a new avenue for simple and efficient modification of OMC with enhanced adsorption performance to expand applications.

16.
Nanoscale ; 10(12): 5725-5730, 2018 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-29537013

RESUMO

Hollow carbon nanospheres (HCNs) with numerous nanopores in their ultrathin carbon shells have been prepared and applied as SPME fiber coatings. Benefiting from its ultrahigh surface area, short diffusion distance, and nitrogen doping, the HCNs-coated fiber demonstrates excellent properties of fast mass transfer, broad-spectrum adsorption and high extraction efficiencies. These encouraging results could offer a benchmark for developing advanced SPME in environment analyses requiring high-performance enrichment of abundant analytes, especially for unknown compounds.

17.
Talanta ; 186: 445-451, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29784386

RESUMO

Novel powdery polymer aerogel (PPA) prepared via the (micro)emulsion polymerization and the following hyper crosslinking reaction was fabricated as stationary phase of capillary column for the first time. Due to its powdery morphology, unique 3D nano-network structure, high surface area and good thermostability, the PPA-coated capillary column demonstrated high-resolution chromatographic separation towards nonpolar and weakly polar organic compounds, including benzene series, n-alkanes, ketone mixtures and trichlorobenzenes. Moreover, the reproducibility, quantitative analysis ability and thermostability of PPA-coated capillary column were also evaluated. The relative standard deviations for three replicate determinations of selected analytes were 0.02-0.11%, 0.12-0.26% and 1.2-3.6% for run-to-run, day-to-day and column-to-column analyses, respectively. The PPA demonstrated good thermostability, and the PPA-coated capillary column was proved to be heat-resistant (270 °C). The results of this study show PPA is an excellent candidate to be employed as stationary phase for gas chromatography capillary.

18.
Anal Chim Acta ; 1029: 30-36, 2018 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-29907287

RESUMO

A cost-effective microporous polymer was synthesized using cheap monomer and catalyst via one-step Scholl-coupling reaction, and its chemical, morphological characteristics and pore structure were investigated. The as-synthesized polymer with large surface area and narrow pore distribution (centered in 1.2 nm) was prepared as a fiber coating for solid-phase microextraction (SPME). Headspace SPME was used for the extraction of the light aromatic compounds, e.g. benzene, toluene, ethylbenzene, m-xylene, naphthalene and acenaphthene. The parameters influencing the extraction and desorption efficiencies, such as extraction temperature and time, salt concentration, desorption temperature and time were investigated and optimized. The results showed that the home-made fiber had superior extraction efficiencies compared with the commercial PDMS fiber. Under the optimized conditions, low detection limits (0.01-1.3 ng/L), wide linear ranges (from 50 to 20000 ng/L to 1-20000 ng/L), good repeatability (4.2-9.3%, n = 6) and reproducibility (0.30-11%, n = 3) were achieved. Moreover, the practical applicability of the coating and proposed method was evaluated by determining the target light aromatic compounds in environmental water samples with satisfied recoveries (83.2%-116%).

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