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1.
Nurs Open ; 10(10): 6912-6922, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37458186

RESUMO

AIMS: The aim of this study was to refine the Falling Risk Assessment Tool in Ophthalmology Inpatients (FRAT) and assess its psychometric properties. DESIGN: A cross-sectional design was used. METHODS: A convenience sample of 730 patients in the ophthalmology department was recruited in a level A tertiary hospital in Guangdong Province from July 2021 to January 2022. Data were analysed using item analysis, interrater reliability, content validation, internal consistency reliability and exploratory factor analysis. RESULTS: Five factors were extracted, accounting for 63.039% of the variance. The interrater reliability of the tool was 0.97. Cronbach's α was 0.658. The I-CVI was 0.75-1.00, the S-CVI/UA was 0.95 and the adjusted mean values of Kappa for indicators ranged from 0.72 to 1.00, as evaluated by the expert group. The FRAT showed satisfactory reliability and validity, and can be used to measure the fall risk assessment in ophthalmology inpatients. PATIENT OR PUBLIC CONTRIBUTION: After explaining the purpose, the patients received our fall risk assessment and answered the corresponding questionnaire questions.


Assuntos
Pacientes Internados , Oftalmologia , Humanos , Psicometria , Reprodutibilidade dos Testes , Estudos Transversais , Medição de Risco
2.
J Tissue Viability ; 32(3): 339-348, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37117126

RESUMO

AIM: Pressure injuries are a significant health care problem worldwide, and many factors influence their occurrence and development. The purpose of this systematic review and meta-analysis was to investigate the role of nutritional status in the development rate of pressure injuries as a potentially modifiable risk factor. METHODS: Study designs included cohort (prospective and retrospective), case-control, and RCTs if the association between nutrition status and pressure injuries was reported. Databases searched included: PubMed, CINAHL, Embase, Scopus, Web of Science, and Cochrane Library on April 20th, 2022. The data were analyzed using OR and random effect model in Revman5.3 and STATA 15 Software. Report this systematic review and meta-analysis according to the PRISMA 2020 statement. RESULTS: A total of 22 separate studies were retained in this systematic review. Of these, 16 articles were included in the meta-analysis. Three studies were assessed as low risk and sixteen as a moderate risk of bias. All RCTs were B quality. The odds ratio of the incidence of pressure injuries in malnourished and non-malnourished patients was 3.66(95% CI: 2.77-4.83). In the three RCTs studies(n = 870), the odds ratio of the incidence of pressure ulcers in patients with standard nutrition to those with specific nutritional interventions was 1.35(95%CI:1.02-1.78). CONCLUSIONS: This systematic review and meta-analysis showed that nutritional status is significantly associated with pressure injuries. Malnutrition can increase the incidence of pressure injuries, and specific nutritional interventions can reduce the incidence of pressure injuries compared to standard nutrition.


Assuntos
Lesões por Esmagamento , Úlcera por Pressão , Humanos , Adulto , Estado Nutricional , Úlcera por Pressão/epidemiologia , Úlcera por Pressão/etiologia , Incidência , Estudos Retrospectivos , Estudos Prospectivos
3.
Am J Otolaryngol ; 43(1): 103193, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34509080

RESUMO

PURPOSE: This study aimed to compare the efficacy between neoadjuvant chemotherapy (NACT) plus intensity-modulated radiotherapy (IMRT) and NACT plus concurrent chemoradiotherapy (CCRT) in patients with nasopharyngeal carcinoma (NPC). MATERIALS AND METHODS: Data from 603 patients with ascending (T4 and N0-1) or descending (T1-2&N3) NPC who were treated at Sun Yat-sen University Cancer Center between October 2009 and February 2012 were retrospectively analyzed. These patients were divided into two groups: NACT+IMRT (n = 302) and NACT+CCRT (n = 301). The primary endpoint was overall survival (OS), which was analyzed using the Kaplan-Meier method, log-rank test, Cox proportional hazards model, and landmark analysis. RESULTS: In univariate analysis, there was no significant difference in 5-year OS between the NACT+IMRT and NACT+CCRT groups (hazard ration [HR]: 0.69; 95% confidence interval [CI]: 0.47-1.01; P = 0.057). However, after adjustment for age (<45 years, ≥45 years), gender, histological stage (I/II, III), T stage (1/2, 3, 4), and N stage (0/1, 2/3), NACT+IMRT was more effective in improving OS, with a 33% decrease in the risk of death than NACT+CCRT (HR: 0.67; 95%CI: 0.45-0.99). Furthermore, landmark analysis indicated that patients in the NACT+IMRT group had higher OS rates within 24 months (HR: 1.83; 95%CI: 1.00-3.34), whereas those treated with NACT+CCRT had higher OS rates after 24 months (HR, 0.47; 95% CI, 0.29-0.77). We also found significant survival benefits of NACT+IMRT regimen in patients younger than 45 years old (HR: 0.27; 95%CI: 0.14-0.49), and in those at stage T3 (HR: 0.50; 95%CI: 0.27-0.93) and stage N2/3 (HR: 0.52; 95%CI: 0.32-0.83). CONCLUSION: Patients with ascending or descending NPC who are treated with NACT+IMRT may have better long-term survival outcomes than those treated with NACT+CCRT, especially the patients younger than 45 years old or in stage T3/N2/N3. Additionally, NACT+IMRT may be a better option than NACT+CCRT in patients within the first 24 months.


Assuntos
Quimiorradioterapia/métodos , Carcinoma Nasofaríngeo/terapia , Neoplasias Nasofaríngeas/terapia , Terapia Neoadjuvante/métodos , Radioterapia de Intensidade Modulada/métodos , Adulto , Fatores Etários , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/mortalidade , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
4.
Artigo em Inglês | MEDLINE | ID: mdl-32714405

RESUMO

OBJECTIVES: This study aims to study the material basis and effective mechanism of musk for ischemic stroke (IS) based on the network pharmacology approach. METHODS: We collected the chemical components and target gene of musk from the BATMAN-TCM analytical platform and identified ischemic stroke-related targets from the following databases: DisGeNET, NCBI-Gene, HPO, OMIM, DrugBank, and TTD. The targets of musk and IS were uploaded to the String database to construct the protein-protein interaction (PPI) network, and then, the key targets were analyzed by topological methods. At last, the function biological process and signaling pathways of key targets were carried out by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis and cluster analysis by using the Database for Annotation, Visualization, and Integrated Discovery (DAVID) server and Metascape platform. RESULTS: A total of 29 active compounds involving 1081 predicted targets were identified in musk and there were 1104 IS-related targets. And 88 key targets of musk for IS were obtained including AKT1, MAPK1/3, TP53, TNF, SRC, FOS, CASP3, JUN, NOS3, and IL1B. The GO and KEGG enrichment analysis suggested that these key targets are mainly involved in multiple pathways which participated in TNF signaling pathway, estrogen signaling pathway, prolactin signaling pathway, neurotrophin signaling pathway, T-cell receptor signaling pathway, cAMP signaling pathway, FoxO signaling pathway, and HIF1 signaling pathway. CONCLUSION: This study revealed that the effective mechanisms of musk against IS would be associated with the regulation of apoptosis, inflammatory response, and gene transcription.

5.
J Oral Maxillofac Surg ; 78(3): 350-356, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31785248

RESUMO

The main complications of tooth extraction include jaw fracture, maxillary sinus damage, adjacent teeth damage, nerve damage, root fracture, infection, bleeding, and swelling. Despite the theoretical possibility that tooth extraction could result in nasolacrimal duct obstruction, to the best of our knowledge, no cases have yet been reported. In the present study, we describe a case in which the nasolacrimal duct was partially obstructed after extraction of an impacted maxillary canine, causing paranasal discomfort and lower eyelid swelling.


Assuntos
Obstrução dos Ductos Lacrimais , Ducto Nasolacrimal , Dente Impactado , Dente Canino , Humanos , Seio Maxilar
6.
PLoS One ; 14(9): e0221964, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31504043

RESUMO

BACKGROUND: Preclinical studies showed that antibiotic exposure played a role in clinical outcomes in patients with chemotherapy via modulation of microbiota. However, it remains unknown whether antibiotic exposure during the bevacizumab therapy affects the clinical outcomes in metastatic colorectal cancer(mCRC) patients. This study aimed to examine the association between the antibiotic medication and the clinical outcomes in mCRC patients with bevacizumab therapy. METHODS: This retrospective cohort analysis included 147 mCRC patients treated with bevacizumab. The hazard ratio of death was estimated using three Cox proportional hazards models with (1) never vs ever; (2) never vs 1-6 days and 7-40 days;(3) increase per day, and further tested using propensity score matching (PSM) and landmark analysis. A smooth curve technique was used to explore the shape of dose-response relationship. RESULTS: Compared with the non-antibiotic group, antibiotic exposure was inversely associated with the mortality in the antibiotic group after adjustment for demographic and other potential confounders (a history of medication: HR, 0.650(95%CI: 0.360 to 1.173); an increase per day: HR, 0.967(CI: 0.924 to 1.011); 1-6 days: HR, 0.859(CI: 0.441 to 1.674); 7-40 days: HR, 0.474(CI: 0.225 to 0.999); P for trend = 0.040). A test for the interaction between sex was statistically significant (p = 0.016). A similar result was found as measured by landmark and PSM analysis. Significant negative dose-response relationship was shown by smooth curve analysis in the male patients but not female after adjustment for confounders(p = 0.028). No association was found between the antibiotic medication and adverse events of bevacizumab. CONCLUSION: Antibiotic exposure could be inversely associated with the mortality in mCRC patients treated with bevacizumab.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Bevacizumab/uso terapêutico , Neoplasias Colorretais/mortalidade , Adulto , Idoso , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Taxa de Sobrevida
7.
J Altern Complement Med ; 23(4): 278-284, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28191857

RESUMO

BACKGROUND: Xerostomia is one of the most common complaints in maintenance hemodialysis (MHD) patients. This problem contributes to excess fluid intake and results in poor survival outcome. Based on Traditional Chinese Medicine (TCM) theory and literature studies, the authors have been practicing auricular acupressure therapy (AAT) to help patients with xerostomia. This pilot study was conducted to demonstrate the potential of AAT for xerostomia in MHD patients. METHODS: Eligible subjects who agreed to participate in this study were recruited and provided with AAT for 4 weeks. The Summated Xerostomia Inventory (SXI), as well as measurement of inter-dialytic weight gain (IDWG), daily inter-dialytic weight gain (daily IDWG), percentage of inter-dialytic weight gain (IDWG%), blood pressure, and biochemical parameters, were completed at baseline and after a 4-week intervention. RESULTS: A total of 26 eligible participants were recruited. Of them, 10 men and 16 women (Mage = 52.92 ± 11.80 years; dialysis vintage 81.86 ± 46.05 months) completed the study. After the 4-week AAT intervention, the SXI scores were significantly decreased compared with baseline (from 10.08 ± 2.26 to 9.04 ± 2.14; p < 0.05). However, the IDWG, daily IDWG, IDWG%, blood pressure, and biochemical parameters did not change significantly after the intervention. CONCLUSION: This study provides preliminary evidence that AAT may be effective in reducing xerostomia intensity for MHD patients.


Assuntos
Acupressão , Acupuntura Auricular , Diálise Renal , Xerostomia/terapia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Aumento de Peso
8.
Artigo em Inglês | MEDLINE | ID: mdl-23832221

RESUMO

Based on the reaction of the active -OH group in fullerol (F) with the dissociated -COOH group in fluorescein isothiocyanate (FITC) to form an F-FITC and the enhanced effect of N, N-dimethylaniline (DMA) on phosphorescence signal of F-FITC, a new phosphorescent labeling reagent (DMA-F-FITC) was developed. What's more, a phosphorescent sensor for the determination of alpha-fetoprotein variant (AFP-V) has been designed via the coupling technique of the high sensitivity for affinity adsorption-solid substrate-room temperature phosphorimetry (AA-SS-RTP) with the strong specificity reaction between DMA-F-FITC-Con A and AFP-V. The DMA-F-FITC increased the number of luminescent molecules in the biological target which improved the sensitivity of phosphorescent sensor. The proposed sensor was responsive, simple, selective and sensitive, and it has been applied to the determination of trace AFP-V in human serum and the forecast of human diseases using phosphorescence emission wavelength of F or FITC, with the results agreed well with those obtained by enzyme-linked immunoassay (ELISA). Meanwhile, the mechanisms for the labeling reaction and the sensing detection of AFP-V were discussed.


Assuntos
Técnicas Biossensoriais , Concanavalina A/química , Doença , Fluoresceína-5-Isotiocianato/análogos & derivados , Fulerenos/química , Luminescência , alfa-Fetoproteínas/análise , Compostos de Anilina , Fluoresceína-5-Isotiocianato/química , Humanos , Umidade , Indicadores e Reagentes , Limite de Detecção , Oxigênio/química , Temperatura , Fatores de Tempo
9.
Luminescence ; 28(5): 634-40, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23023763

RESUMO

The rhodamine 6G(+) -perphenazine (Rhod 6G(+) -PPH) compound is formed in the ester-exchange reaction between -OH of PPH and -COOC2 H5 of Rhod 6G(+) . PPH was oxidized to a red compound (PPH') in the presence of K2 S2 O8 . Interestingly, the room temperature phosphorescence (RTP) of Rhod 6G(+) was quenched because the -OH of PPH' reacted with -COOC2 H5 of Rhod 6G(+) -PPH to form Rhod 6G(+) -PPH' and PPH, which decreased the π-electron density (δ) of the carbon atom in the Rhod 6G(+) -PPH' conjugated system and enhanced the nonradiation energy loss of the excited Rhod 6G(+) of the triplet state. The PPH content was directly proportional to the ΔIp of the system. Thus, a new catalytic solid-substrate room temperature phosphorimetry (SSRTP) method was established for the determination of PPH. The method had high sensitivity (the limit of detection was 0.019 fg/spot, corresponding to a concentration of 4.8 × 10(-14) g/mL; the sampling quantity was 0.40 µL/spot), good selectivity, convenience and speed. The analytical results were in accordance with those of high-performance liquid chromatography (HPLC). The structures of Rhod 6G(+) , PPH and Rhod 6G(+) -PPH were characterized by infrared spectra. The reaction mechanism by which PPH was determined is discussed.


Assuntos
Medições Luminescentes/métodos , Perfenazina/análise , Rodaminas/química , Temperatura , Catálise , Elétrons , Estrutura Molecular
10.
Analyst ; 137(22): 5346-51, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-23033064

RESUMO

Gold nanoclusters (AuNCs) were synthesized by a macromolecules template using bovine serum albumin (BSA) as stabilizer which can emit red photoluminescence under illumination of ultraviolet light. The fluorescence intensity of AuNCs enhanced through decreasing the surface defects of AuNCs modified with cysteine, herein we present a novel fluorometry for determination of trace cysteine. This method with a wider linear range from 2.0 to 800 nmol mL(-1), higher sensitivity (detection limit was 1.2 nmol mL(-1)) and better selectivity has been utilized to determine cysteine content in real samples, and the results were in a good agreement with those determined by electrochemical biosensor. At the same time, the structures of AuNCs and AuNCs-cysteine were characterized by Fourier-transform infrared spectroscopy (FTIR) and high resolution transmission electron microscopy (HRTEM) and the mechanism of the proposed assay for the detection of cysteine has been discussed.


Assuntos
Cisteína/análise , Fluorometria , Ouro/química , Nanopartículas Metálicas/química , Soroalbumina Bovina/química , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo
11.
Anal Chim Acta ; 744: 60-7, 2012 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-22935375

RESUMO

The present study proposed a simple sensitive and specific immunoassay for the quantification of calcitonin (CT) in human serum with water-soluble multi-walled carbon nanotubes (MWNTs). The COOH group of MWNTs could react with the NH group of rhodamine S (Rhod.S) molecules to form Rhod.S-MWNTs, which could emit room temperature phosphorescence (RTP) on acetate cellulose membrane (ACM) and react with Tween-80 to form micellar compound. Tween-80-Rhod.S-MWNTs (TRM), as a phosphorescent labelling reagent, could dramatically enhance the RTP signal of the system. The developed TRM phosphorescent reagent was used to label anti-calcitonin antibody (Ab(CT)) to form the TRM-Ab(CT) labelling product, which could take high specific immunoreaction with CT, and the ΔI(p) (= I(p2)-I(p1), I(p2) and I(p1) were the phosphorescence intensity of the test solution and the blank sample, respectively) of the system was linear to the content of CT. Hence, a new solid substrate room temperature phosphorescence immunoassay (SSRTPIA) was established for the determination of CT in human serum. This sensitive (limit of quantification (LOQ) was 8.0×10(-14) g mL(-1)), accurate, selective and precise method has been applied to determine CT in human serum and predict primary osteoporosis and fractures, with the results in good agreement with those obtained by chemiluminescence immunoassay (CLIA). Simultaneously, the structure of MWNTs was characterized with scanning electron microscopy (SEM) and infrared spectroscopy (IR), and the reaction mechanisms of both labelling Ab(CT) with TRM and SSRTPIA for the determination of trace CT were discussed.


Assuntos
Calcitonina/sangue , Corantes Fluorescentes/química , Nanotubos de Carbono/química , Polissorbatos/química , Rodaminas/química , Anticorpos/imunologia , Reações Antígeno-Anticorpo , Calcitonina/imunologia , Humanos , Solubilidade , Água/química
12.
Artigo em Inglês | MEDLINE | ID: mdl-22858611

RESUMO

Rhodamine S could emit strong and stable room temperature phosphorescence (RTP) on polyamide membrane (PAM) in the presence of heavy atom perturber Pb(2+). When Rhodamine S-piperidine solution was dropped on PAM, the red (Rhod.S)(n)-P-SOR (Rhod.S, (Rhod.S)(n), P and SOR refer to alizarin red S, multiple Rhod.S molecules, piperidine and self-ordered ring, respectively) formed on PAM, leading to the enhancement of room temperature phosphorimetry (RTP) intensity (I(p), 117.2) of (Rhod.S)(n)-P-SOR system, which was 2.4 times higher than that without SOR (I(p), 48.1). Wheat germ agglutinin (WGA) was labelled with (Rhod.S)(n)-P-SOR by the -NH- of Rhod.S reacting with the -COOH of WGA to form WGA-(Rhod.S)(n)-P-SOR. The formation of WGA-AP-WGA-(Rhod.S)(n)-P-SOR in the affinity adsorption (AA) reaction carried out between the -COOH of WGA in WGA-(Rhod.S)(n)-P-SOR and the -NH(2) of alkaline phosphatase (AP) caused the RTP intensity (ΔI(p)) of the WGA-AP-WGA-(Rhod.S)(n)-P-SOR system 7.8 times larger than that without (Rhod.S)(n)-P-SOR. Therefore, the coupling technique of SOR and solid substrate-room temperature phosphorimetry (SS-RTP) for the determination of trace AP has been established. This method possessed good selectivity, high sensitivity (Detection limit (L.D) was 3.4×10(-16)gmL(-1)) and accuracy, and it has been applied to the determination of trace AP in human serum and the forecast of human diseases, and the results agreed well with those obtained by enzyme-linked immunoassay (ELISA). Besides, the mechanism of the coupling technique for the determination of AP was discussed.


Assuntos
Fosfatase Alcalina/sangue , Doença , Medições Luminescentes/métodos , Antraquinonas/química , Antraquinonas/metabolismo , Soluções Tampão , Humanos , Limite de Detecção , Piperidinas/química , Piperidinas/metabolismo , Rodaminas/química , Rodaminas/metabolismo , Solventes , Especificidade por Substrato , Temperatura , Aglutininas do Germe de Trigo/metabolismo
13.
Anal Biochem ; 431(1): 19-29, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22906688

RESUMO

Taking advantage of the cutting effect of the strong oxidation of benzoyl peroxide [(C(6)H(5)CO)(2)O(2)] on the end of multiwall carbon nanotubes (MWNTs) to obtain water-soluble multiwall nanotubes (MWNTs') and the spiking effect of polyacrylamide (PA) on the room temperature phosphorescence (RTP) of MWNTs', a new phosphorescent labeling reagent, MWNTs'-PA, has been developed in this study. The product ß-Ab(HCG)-MWNTs'-PA obtained by MWNTs'-PA labeling human chorionic gonadotropin-ß-subunit three-dimensional core monoclonal antibody (ß-Ab(HCG)) not only could maintain good RTP characteristics of MWNTs' but also could take specific immunoreaction with ß-HCG to form ß-HCG- ß-Ab(HCG)-MWNTs'-PA, resulting in the increase of MWNTs' RTP signal. Thus, a new solid substrate room temperature phosphorescence immunoassay (SSRTPIA) for the determination of ß-HCG has been established. The limits of detection (LODs) of the new method were 0.021pgspot(-1) for the direct way at 447/615nm (λ(ex)(max)/λ(em)(max)) and 0.016pgspot(-1) for the sandwich way at 447/614nm (λ(ex)(max)/λ(em)(max)). This sensitive, accurate, and precise method was used to determine ß-HCG and diagnose human diseases by the direct way or the sandwich way, with the results coinciding with those obtained by chemiluminescence immunoassay. Meanwhile, the mechanisms of MWNTs' labeling ß-Ab(HCG) and determining ß-HCG are also discussed.


Assuntos
Gonadotropina Coriônica/sangue , Imunoensaio , Substâncias Luminescentes/química , Nanotubos de Carbono/química , Resinas Acrílicas/química , Anticorpos Monoclonais/imunologia , Feminino , Humanos , Concentração de Íons de Hidrogênio , Medições Luminescentes , Oxigênio/química , Gravidez , Temperatura
14.
Artigo em Inglês | MEDLINE | ID: mdl-22580148

RESUMO

This paper is trying to research the developing status of carbon dots (CDs), and the results show that the simple, rapid and high yield synthetic methods for CDs and the application of CDs in biological science and analysis field will certainly become an inevitable development trend in the future. The CDs obtained by microwave possess excellent optical properties including UV-Vis absorption, fluorescence and room temperature phosphorescence. Under the conditions of 30 °C and 10 min, the fluorescence signal (F) of CDs not only could be enhanced by hexadecyltrimethylammonium bromide (CTAB), Triton X-100, Na(2)S, Na(2)C(2)O(4) and NH(3).H(2)O, but also could be quenched by sodium dodecyl sulfate, KBrO(3), K(2)S(2)O(8), NaIO(4), ascorbic acid, NaBH(4), HNO(3), HCl, H(2)SO(4), CH(3)COOH and most metal ions, with the λ(em)(max) blue or red shifting in varying degrees, indicating the potential values of CDs in analytical application. Besides, the sensitive response of F to pH showed the promise of developing a new pH sensor with CDs.


Assuntos
Carbono/química , Luminescência , Pontos Quânticos , Ácidos/química , Álcalis/química , Concentração de Íons de Hidrogênio , Íons , Microscopia Eletrônica de Transmissão , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Temperatura , Fatores de Tempo
15.
Analyst ; 137(11): 2637-42, 2012 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-22531278

RESUMO

Based on the ability of lysine (Lys) to enhance the fluorescence intensity of bovine serum albumin modified-carbon dots (CDs-BSA) to decrease surface defects and quench fluorescence of the CDs-BSA-Lys system in the presence of Cu(2+) under conditions of phosphate buffer (PBS, pH = 5.0) at 45 °C for 10 min, a sensitive Lys enhancing CDs-BSA fluorescent probe was designed. The environment-friendly, simple, rapid, selective and sensitive fluorescent probe has been utilized to detect Cu(2+) in hair and tap water samples and it achieved consistent results with those obtained by inductively coupled plasma mass spectroscopy (ICP-MS). The mechanism of the proposed assay for the detection of Cu(2+) is discussed.


Assuntos
Carbono/química , Cobre/análise , Corantes Fluorescentes/química , Lisina/química , Soroalbumina Bovina/química , Espectrometria de Fluorescência , Animais , Bovinos , Água Doce/análise , Cabelo/química , Concentração de Íons de Hidrogênio , Íons/química , Temperatura
16.
J Fluoresc ; 22(4): 1087-94, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22527301

RESUMO

Under the condition of 60 °C and 20 min at pH 6.12, chlorpromazine hydrochloride (CPZ) could react with fluorescein isothiocyanate (FITC) to produce FITC-CPZ, which increased the π-electron density (δ) of carbon atom in FITC conjugated system and the room temperature phosphorescence (RTP) intensity of FITC. Thus, a new solid substrate room temperature phosphorimetry (SSRTP) for the determination of residual CPZ was established. The regression equation of working curve was ΔI (p) = 4.254 + 7.906 m(CPZ) (ag spot(-1)) with the correlation coefficient (r) of 0.9990 in the range of 0.036-9.6 ag spot(-1) (corresponding concentration: 0.090-24 fg ml(-1), sample volume: 0.40 µl spot(-1)), and the detection limit (LD) was 0.018 ag spot(-1) (corresponding concentration: 4.5 × 10(-17) g ml(-1)). This method with wide linear range and high sensitivity was not only used to diagnose human disease based on the correlation between the residual quantity and lethal dose of CPZ in human serum, but also used to determine residual CPZ in biological samples with the results consisting with those obtained by gas chromatography (GC), showing good accuracy. The constituent of FITC-CPZ was analyzed by GC-MS (mass spectrometry) and the reaction mechanism of SSRTP for the determination of trace CPZ was also discussed.


Assuntos
Clorpromazina/análise , Clorpromazina/química , Resíduos de Drogas/análise , Resíduos de Drogas/química , Medições Luminescentes/métodos , Temperatura , Calibragem , Clorpromazina/sangue , Fluoresceína-5-Isotiocianato/química , Humanos , Modelos Lineares
17.
Anal Chim Acta ; 723: 76-82, 2012 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-22444576

RESUMO

Al(3+) could react with quercetin (Q) to form [AlQ](3+) complex which could be used as a template for the preparation of poly (vinyl alcohol)-[AlQ](3+) complex imprinting (PVA-C-I). The [AlQ](3+) not only had good matching ability and selectivity with the cavity of PVA-C-I, but also could react with the fluorescein isothiocyanate anion (FITC(-)) on the outside of cavity by electrostatic interaction to form ion-association complex [AlQ](3+)·[(FITC)(-)](3). The ion-association complex could emit strong and stable room temperature phosphorescence (RTP) on polyamide membrane (PAM) and the ΔI(p) of the system had linear relationship with the content of Q, showing the highly selective identification of PVA-C-I to Q. Thus, a new coupling technique for the determination of trace Q based on solid substrate room temperature phosphorimetry and poly (vinyl alcohol) complex imprinting (PVA-C-I-SSRTP) was established. The linear range and limit of detection (LOD) of this method were 0.010-2.0 (×10(-12) g mL(-1)) and 2.0×10(-14) g mL(-1), respectively, showing wide linear range and high sensitivity of PVA-C-I-SSRTP. This method was used to determine the content of Q in waste water, and the results are consistent with those by spectrofluorimetry. Meanwhile, the mechanism for the determination of Q using PVA-C-I-SSRTP was also discussed.


Assuntos
Complexos de Coordenação/química , Álcool de Polivinil/química , Quercetina/análise , Espectrometria de Fluorescência , Alumínio/química , Fluoresceína-5-Isotiocianato/química , Impressão Molecular , Nylons/química , Eletricidade Estática , Temperatura , Poluentes Químicos da Água/química
18.
Luminescence ; 27(5): 346-51, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22021248

RESUMO

3.5-Generation polyamidoamine dendrimers (3.5-G-D) emitted strong and stable room-temperature phosphorescence (RTP) on filter paper when Pb2+ was used as a heavy atom perturber. The RTP signal of 3.5-G-D was sharply enhanced upon the formation of 3.5-G-D-Tween-80 micelle compound. The complex Cd2+ -3.5-G-D-Tween-80, generated in the coordination reaction between Cd2+ and the tertiary amidocyanogen on the outer layer of 3.5-G-D in 3.5-G-D-Tween-80 micelle compound, could catalyze KBrO3 to oxidize 3.5-G-D in 3.5-G-D-Tween-80, which caused the sharp quenching of the RTP signal of the system. The phosphorescence intensity change (ΔI(p) ) of the system had a linear relationship with the content of Cd2+. Thus a new catalytic solid substrate-room-temperature phosphorimetry (SS-RTP) for the determination of trace cadmium has been established. This highly selective and sensitive method has been applied to determine trace cadmium in biological samples with a limit of detection (LD) of 1.2 ag per spot (when the sample volume was 0.4 µL per spot, the corresponding concentration was 3.0 × 10(-15) g mL(-1) ), the results agreeing with those obtained by atomic absorption spectrometry. The mechanism of catalytic SS-RTP for the determination of trace cadmium was also discussed.


Assuntos
Cádmio/química , Dendrímeros/química , Medições Luminescentes/métodos , Poliaminas/química , Polissorbatos/química , Catálise , Limite de Detecção , Temperatura
19.
Anal Chim Acta ; 708(1-2): 130-3, 2011 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-22093355

RESUMO

A gold nanorods (GNRs) nonaggregation-based colorimetric probe has been developed for the detection of S(2-) based on that the longitudinal surface plasmon resonance absorption wavelength (LPAW) of GNRs red shifts (Δλ) and the color of the solution distinctly changes on account of the faster stripping of GNRs along longitudinal axis than transverse axis in the process of GNRs reacting with S(2-) ions to form Au(2)S complexes on the GNRs surfaces. The GNRs probe exhibits highly sensitive and selective response toward S(2-) with a wide linear range from 10.0 to 10000.0 µM. The proposed colorimetric probe can be used to visibly detect S(2-) in water samples on line in 15 min with the results agreeing well with those of the optical sensor, showing its great practicality. Moreover, the detection mechanism of the probe is also discussed.


Assuntos
Ouro/química , Nanotubos/química , Sulfetos/análise , Ressonância de Plasmônio de Superfície , Absorção , Colorimetria
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 84(1): 221-6, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21993256

RESUMO

Calcein (R) could not only emit strong and stable room temperature phosphorescence (RTP) on filter paper using I(-) as perturber, but also could be oxidized by H(2)O(2) to form a non-phosphorescence compound (R'), resulting in the quenching of RTP signal of R. Moreover, the ortho-hydrogen of phenolic hydroxyl in R took condensation reaction with rhamnose (Rha) to produce non-phosphorescence compound (R-Rha) causing the RTP signal of R to further quench, and R-Rha was oxidized by H(2)O(2) to form R' and Rha, bringing about the sharp RTP signal quenching of R. Thus, a new solid substrate room temperature phosphorimetry (SSRTP) for the determination of trace Rha based on its strong catalytic effect on H(2)O(2) oxidizing R has been established, with the detection limit (LD) of 7.8zgspot(-1) (corresponding concentration: 2.0×10(-17) gm l(-1), sample volume: 0.40 µl spot(-1)). This method has been applied to determine trace Rha in cigarettes and jujubes, with the results coinciding well with those determined by a high performance liquid chromatography (HPLC). The component of R-Rha also was analyzed by means of HPLC, mass spectrometer and nuclear magnetic resonance (NMR) measurements. The mechanism of catalytic SSRTP for the determination of trace Rha was discussed.


Assuntos
Fluoresceínas/química , Medições Luminescentes/métodos , Ramnose/análise , Ramnose/química , Temperatura , Catálise , Peróxido de Hidrogênio/química , Oxirredução , Espectrometria de Fluorescência
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