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1.
BrJP ; 6(3): 244-250, July-sept. 2023. tab
Article in English | LILACS-Express | LILACS | ID: biblio-1520299

ABSTRACT

ABSTRACT BACKGROUND AND OBJECTIVES: Rheumatoid arthritis is an inflammatory, chronic and autoimmune disease that causes joint damage and can lead to physical disability. Patients with chronic and debilitating diseases such as arthritis need to adapt to the new reality. These changes may have less impact on patients with greater self-efficacy and resilience. Psychosocial factors influence the quality of life (QoL) of these patients, so the aim of this study was to assess resilience in this population and its relationship with pain, functional capacity and disease activity. METHODS: This is a cross-sectional study carried out with patients at a medical specialties clinic, using a sociodemographic, a clinical-laboratory, a health assessment, a disease activity score questionnaires and the Wagnild and Young Resilience Scale. The data was analyzed using Fisher's Exact, Chi-square, Student's t and ANOVA tests. RESULTS: 120 patients participated in the study, 89.2% female, mean age 56.9 ± 10.7 years. Pain was classified as severe by 40.8%, 65.8% had disease in remission and 50.8% had mild disability. The resilience of 49.2% was high. There was an association between lower resilience and: presence of painful joints (p=0.004) and greater pain intensity (p=0.014). There was a lower average of resilience (130.95) in participants with severe disability. CONCLUSION: Patients with less resilient rheumatoid arthritis had greater functional disability, painful joints and greater pain intensity. In addition, from the moment additional measures are adopted, such as educational actions and behavioral strategies, with an emphasis on resilience, which help in the control and clinical outcome of the disease, there will certainly be a positive impact on the quality of life of these patients.


RESUMO JUSTIFICATIVA E OBJETIVOS: A artrite reumatoide é uma doença inflamatória, crônica e autoimune, que acarreta lesão articular e pode ocasionar incapacidade física. Pacientes com doenças crônicas e debilitantes como a artrite necessitam se adaptar à nova realidade. Essas mudanças podem ser menos impactantes em pacientes com maior autoeficácia e resiliência. Os fatores psicossociais exercem influência na qualidade de vida (QV) desses pacientes, portanto o objetivo deste estudo foi avaliar a resiliência nessa população e sua relação com dor, capacidade funcional e atividade da doença. MÉTODOS: Trata-se de uma pesquisa transversal, realizada com pacientes de uma clínica de especialidades médicas, através dos questionários sociodemográfico, clínico-laboratorial, de avaliação da saúde, de escore da atividade da doença,e avaliação da saúde, de escore da atividade da doença, e da escala de Resiliência de Wagnild e Young. A análise dos dados foi feita através dos testes Exato de Fisher, Qui-quadrado, t de Student e ANOVA. RESULTADOS: Participaram do estudo 120 pacientes, sendo 89,2% do sexo feminino, com média de idade de 56,9±10,7 anos. A dor foi classificada como intensa por 40,8%; 65,8% dos pacientes estavam com doença em remissão e 50,8% com incapacidade leve. A resiliência de 49,2% foi elevada. Foi verificada uma associação entre menor resiliência e: presença de articulações dolorosas (p=0,004) e maior intensidade de dor (p=0,014). Foi verificada menor média de resiliência (130,95) nos participantes com incapacidade grave. CONCLUSÃO: Pacientes com artrite reumatoide menos resilientes apresentaram maior incapacidade funcional, articulações dolorosas e maior intensidade de dor. Além disso, a partir do momento em que se adota medidas adicionais, tais como ações educativas e estratégias comportamentais, com ênfase na resiliência, que auxiliem no controle e no desfecho clínico da doença, certamente haverá impacto positivo na QV dos pacientes.

2.
Biosensors (Basel) ; 12(8)2022 Aug 17.
Article in English | MEDLINE | ID: mdl-36005045

ABSTRACT

A new electrochemical DNA biosensor based on mercaptopropionic acid (MPA)-capped ZnS quantum dots (MPA-ZnS QDs) immobilization matrix for covalent binding with 20-base aminated oligonucleotide has been successfully developed. Prior to the modification, screen-printed carbon paste electrode (SPE) was self-assembled with multilayer gold nanoparticles (AuNPs) and cysteamine (Cys). The inclusion of MPA-ZnS QDs semiconducting material in modified electrodes has enhanced the electron transfer between the SPE transducer and DNA leading to improved bioanalytical assay of target biomolecules. Electrochemical studies performed by cyclic voltammetry (CV) and differential pulsed voltammetry (DPV) demonstrated that the MPA-ZnS QDs modified AuNPs electrode was able to produce a lower charge transfer resistance response and hence higher electrical current response. Under optimal conditions, the immobilized synthetic DNA probe exhibited high selectivity towards synthetic target DNA. Based on the DPV response of the reduction of anthraquinone monosulphonic acid (AQMS) redox probe, the MPA-ZnS QDs-based electrochemical DNA biosensor responded to target DNA concentration from 1 × 10-9 µM to 1 × 10-3 µM with a sensitivity 1.2884 ± 0.12 µA, linear correlation coefficient (R2) of 0.9848 and limit of detection (LOD) of 1 × 10-11 µM target DNA. The DNA biosensor exhibited satisfactory reproducibility with an average relative standard deviation (RSD) of 7.4%. The proposed electrochemical transducer substrate has been employed to immobilize the aminated Arowana fish (Scleropages formosus) DNA probe. The DNA biosensor showed linearity to target DNA from 1 × 10-11 to 1 × 10-6 µM (R2 = 0.9785) with sensitivity 1.1251 ± 0.243 µA and LOD of 1 × 10-11 µM. The biosensor has been successfully used to determine the gender of Arowana fish without incorporating toxic raw materials previously employed in the hazardous processing conditions of polypyrrole chemical conducting polymer, whereby the cleaning step becomes difficult with thicker films due to high levels of toxic residues from the decrease in polymerization efficacy as films grew.


Subject(s)
Biosensing Techniques , Metal Nanoparticles , Quantum Dots , Animals , DNA/chemistry , DNA Probes , Electrochemical Techniques , Electrodes , Gold/chemistry , Metal Nanoparticles/chemistry , Polymers , Pyrroles , Quantum Dots/chemistry , Reproducibility of Results , Sulfides , Zinc Compounds
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 267(Pt 2): 120535, 2022 Feb 15.
Article in English | MEDLINE | ID: mdl-34749257

ABSTRACT

Optical biosensor for the detection of formaldehyde has been developed based on the transparent enzymatic stacked membranes system on the glass substrate, and employing optical absorption transducer with H+ ion-selective Nile Blue chromoionophore (NBCM) dye-doped methacrylic acrylic (MB28) copolymer membrane as the optode membrane. Alcohol oxidase (AOx) enzymes were entrapped within the biocompatible sol-gel matrix and deposited on top of the pH optode membrane. As the uppermost catalytic membrane catalyzes the oxidative conversion of formaldehyde to formic acid and hydrogen peroxide, the immobilized NBCM undergoes protonation reaction and forms HNBCM+, the dark blue ion-chromoionophore complex via H+ ion transfer reaction within the soft and flexible MB28 polymeric membrane. This rendered the enzymatic optode membrane absorbed a high yellow light intensity from the light source and exhibited maximum absorption peaks at 610 and 660 nm. Optical evaluation of formaldehyde by means on UV-vis absorption transduction of the enzymatic stacked membranes demonstrated rapid response time of 10 min with high sensitivity, good linearity and high reproducibility across a wide formaldehyde concentration range of 1 × 10-3-1 × 103 mM (R2 = 0.9913), and limit of detection (LOD) at 1 × 10-3 mM, which could be useful for formaldehyde assay in industrial, agricultural, environmental, food and beverages as well as medical samples. The formaldehyde concentration in snapper fish, pomfret fish and threadfin fish samples determined by the proposed optical enzymatic biosensor were very much close to the formaldehyde concentration values determined by the UV-vis spectrophotometric NASH standard method based on the statistical t-test. This suggests that the optical biosensor can be used as a reliable method for quantitative determination of formaldehyde levels in food samples.


Subject(s)
Biosensing Techniques , Enzymes, Immobilized , Alcohol Oxidoreductases , Animals , Formaldehyde , Hydrogen-Ion Concentration , Reproducibility of Results
4.
J Food Sci ; 87(1): 8-35, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34954819

ABSTRACT

Increasing public awareness of food quality and safety has prompted a rapid increase in food authentication of halal food, which covers the production method, technical processing, identification of undeclared components, and species substitution in halal food products. This urges for extensive research into analytical methods to obtain accurate and reliable results for monitoring and controlling the authenticity of halal food. Nonetheless, authentication of halal food is often challenging because of the complex nature of food and the increasing number of food adulterants that cause detection difficulties. This review provides a comprehensive and impartial overview of recent studies on the analytical techniques used in the analysis of halal food authenticity (from 1980 to the present, but there has been no significant trend in the choice of techniques for authentication of halal food during this period). Additionally, this review highlights the classification of different methodologies based on validity measures that provide valuable information for future developments in advanced technology. In addition, methodological developments, and novel emerging techniques as well as their implementations have been explored in the evaluation of halal food authentication. This includes food categories that require halal authentication, illustrating the advantages and disadvantages as well as shortcomings during the use of all approaches in the halal food industry.


Subject(s)
Food Quality , Food
5.
Rev. bras. enferm ; 75(3): e20201341, 2022. tab
Article in English | LILACS-Express | LILACS, BDENF - Nursing | ID: biblio-1351705

ABSTRACT

ABSTRACT Objectives: to analyze and compare levels of stress and resilience in nurses before and after the assessment for maintenance of the Hospital Accreditation Certification. Methods: quantitative, observational, and longitudinal research, with 53 nurses from a philanthropic hospital, in the Rio Grande do Sul. Data collected in two stages, March, and July 2019, before the assessment visit and 60 days after, using the Bianchi Stress Scale and Resilience Scale. Descriptive and analytical statistics were employed. Results: the majority of participants showed an average stress level before and after the evaluation. The highest stress scores were related to Domains E (coordination of unit activities) and C (activities related to personnel administration). In both moments of the study, the participants had medium and high resilience. Conclusions: managing people, processes, and assistance are stressful activities in the Accreditation process and increase the nurses' stress levels.


RESUMEN Objetivos: analizar y comparar niveles de estrés y resiliencia de enfermeros antes y después de evaluación para manutención de Certificación de Acreditación de Hospitales. Métodos: investigación cuantitativa, observacional y longitudinal, con 53 enfermeros de hospital filantrópico, en Rio Grande del Sul. Datos recolectados en dos etapas, marzo y julio de 2019, antes de la invitación de evaluación y 60 días después. Utilizado Escala de Estrés Bianchi y Escala de Resiliencia. Empleado estadística descriptiva y analítica. Resultados: mayoría de los participantes presentaron nivel mediano de estrés antes y después de la evaluación. Mayores escores de estrés fueron referentes a Dominios E (coordinación de actividades de la unidad) y C (actividades relacionadas a administración de personal). En los dos momentos, los participantes encontraban con capacidad de resiliencia mediana y alta. Conclusiones: gerenciar personas, procesos y asistencia son actividades agotadoras en la Acreditación y elevan los niveles de estrés de los enfermeros.


RESUMO Objetivos: analisar e comparar níveis de estresse e resiliência de enfermeiros antes e depois da avaliação para manutenção da Certificação de Acreditação Hospitalar. Métodos: pesquisa quantitativa, observacional e longitudinal, com 53 enfermeiros de um hospital filantrópico, no estado do Rio Grande do Sul. Dados coletados em duas etapas, março e julho de 2019, antes da visita de avaliação e 60 dias depois. Utilizou-se Escala Bianchi de Stress e Escala de Resiliência. Empregouse estatística descritiva e analítica. Resultados: a maioria dos participantes apresentou nível médio de estresse antes e depois da avaliação. Maiores escores de estresse foram referentes aos Domínios E (coordenação das atividades da unidade) e C (atividades relacionadas à administração de pessoal). Nos dois momentos do estudo, os participantes encontravam-se com capacidade de resiliência média e alta. Conclusões: gerenciar pessoas, processos e assistência são atividades desgastantes no processo de Acreditação e elevam os níveis de estresse dos enfermeiros.

6.
Rev Bras Enferm ; 75(3): e20201341, 2021.
Article in English, Portuguese | MEDLINE | ID: mdl-34852118

ABSTRACT

OBJECTIVES: to analyze and compare levels of stress and resilience in nurses before and after the assessment for maintenance of the Hospital Accreditation Certification. METHODS: quantitative, observational, and longitudinal research, with 53 nurses from a philanthropic hospital, in the Rio Grande do Sul. Data collected in two stages, March, and July 2019, before the assessment visit and 60 days after, using the Bianchi Stress Scale and Resilience Scale. Descriptive and analytical statistics were employed. RESULTS: the majority of participants showed an average stress level before and after the evaluation. The highest stress scores were related to Domains E (coordination of unit activities) and C (activities related to personnel administration). In both moments of the study, the participants had medium and high resilience. CONCLUSIONS: managing people, processes, and assistance are stressful activities in the Accreditation process and increase the nurses' stress levels.


Subject(s)
Nurses , Nursing Staff, Hospital , Resilience, Psychological , Accreditation , Brazil , Hospitals , Humans , Surveys and Questionnaires
7.
Preprint in English | medRxiv | ID: ppmedrxiv-21262535

ABSTRACT

COVID-19 was characterized by cytokine storm and endothelial dysfunction in severely ill patients. As the severity of the infection was corelated with ethnicity, this study aimed to assess the correlation of proinflammatory cytokine serum level and COVID-19 symptoms within the Palestinian population. In cross-sectional study, serum samples of 27 non-hospitalized patients and 63 hospitalized patients SARS-CoV-2 infected patients, were tested for total antibodies, IL-6, TNF-, IFN-{gamma} and IL-1{beta} using the ELISA test. Results showed that most common symptoms within patients were Joint pain, cough, and fever (73.3%, 69.7% and 50% respectively). Serum total antibodies (IGs) levels in non-hospitalized patients were higher than hospitalized patients ((44.7 COI and 9.2 COI). TNF- and IL-6 were lower in non-hospitalized patients compared to hospitalized patients (48{+/-}17.9 pg/ml, 193.3{+/-}350.5 pg/ml respectively). On the other hand, IFN-{gamma}, in non-hospitalized patients (1{+/-}2 IU/ml) was significantly higher than hospitalized patients (0.4{+/-}0.26 IU/ml). IL-1{beta} was slightly lower in hospitalized patients (8.8{+/-}13.6 pg/ml) compared to non-hospitalized patients (12.5{+/-}24.5 pg/ml). Common mild symptoms of COVID-10 were negatively associated with proinflammatory cytokines serum level. In conclusion as it with other populations worldwide, IL-6 and TNF- are playing a major role in the complications of SARS-CoV-2 infection. Monitoring the two cytokines is crucial for management and treatment of complicated consequence of COVID-19.

8.
Acta Crystallogr E Crystallogr Commun ; 73(Pt 10): 1530-1533, 2017 Oct 01.
Article in English | MEDLINE | ID: mdl-29250374

ABSTRACT

In the title compound, C14H18N2O2S, the piperidine ring has a chair conformation. Its mean plane is twisted with respect to the 4-meth-oxy-benzoyl ring, with a dihedral angle of 63.0 (3)°. The central N-C(=S)-N(H)-C(=O) bridge is twisted with an N-C-N-C torsion angle of 74.8 (6)°. In the crystal, mol-ecules are linked by N-H⋯O and C-H⋯O hydrogen bonds, forming chains along the c-axis direction. Adjacent chains are linked by C-H⋯π inter-actions, forming layers parallel to the ac plane. The layers are linked by offset π-π inter-actions [inter-centroid distance = 3.927 (3) Å], forming a supra-molecular three-dimensional structure.

9.
Anal Chim Acta ; 951: 133-139, 2017 Jan 25.
Article in English | MEDLINE | ID: mdl-27998481

ABSTRACT

The use of a polymer inclusion membrane (PIM) as a sensing material is a new approach to overcome the selectivity and stability drawbacks of the optical chemical sensor (optode). In this study, non-plasticized PIM containing poly(vinyl chloride) as a support base, sodium morin-5-sulfonate (NaMSA) as a reagent and Aliquat 336 as a fixed carrier (ionophore) was prepared and its performance was tested for application in an optode to determine Al3+ ions. The results showed that PIM properties are greatly influenced by the membrane composition. The studies revealed that the optode response was dependent on film thickness, the presence of plasticizer, stirring effect, concentration of NaMSA, concentration of Aliquat 336 and pH of the aqueous solution used. The dynamic range of Al3+ ions concentration determined using this optode was linear from 5.19 × 10-7 to 6.00 × 10-5 mol L-1 and the calculated limit of detection (L.O.D.) was found to be 4.07 × 10-7 mol L-1. The maximum emission wavelength (λem) for the PIM based optode was 512 nm. Scanning electron microscopy analysis of the PIM revealed that a dense texture was formed. Fourier transform infra-red and thermal gravimetry analysis characterizations proved that all of the constituents of the PIM remain within the membrane. The PIM developed in this work was found to be stable, has good mechanical strength, and is sensitive and reusable. Lastly, the PIM was successfully applied as an optical sensor for determination of Al3+ ions in an aqueous solution.

10.
Sci Rep ; 6: 38748, 2016 12 13.
Article in English | MEDLINE | ID: mdl-27958299

ABSTRACT

Co (II) complex (CMLA) was investigated to evaluate the rate of wound healing in rats. Animals were placed into four groups: gum acacia, Intrasite gel, 10 and 20 mg/ml of CMLA. Wounds were made on the dorsal neck area, then treated with Intrasite gel or CMLA; both of these treatments led to faster healing than with gum acacia. Histology of the wounds dressed with CMLA or Intrasite gel displayed a smaller scar width, required less time to heal and showed more collagen staining and fewer inflammatory cells in comparison to wounds dressed with the vehicle. Immunohistochemistry for Hsp70 and TGF-ß showed greater staining intensity in the treated groups compared to the vehicle group. Bax staining was less intense in treated groups compared to the vehicle group, suggesting that CMLA and Intrasite gel provoked apoptosis, responsible for the development of granulation tissue into a scar. CD31 protein analysis showed that the treated groups enhanced angiogenesis and increased vascularization compared to the control group. Furthermore, a significant increase in the levels of GPx and SOD and a decrease in MDA were also observed in the treated groups. This results suggest that CMLA is a potentially promising agent for the wounds treatment.


Subject(s)
Antioxidants , Cobalt , Coordination Complexes , Wound Healing/drug effects , Animals , Antioxidants/chemical synthesis , Antioxidants/chemistry , Antioxidants/pharmacology , Cobalt/chemistry , Cobalt/pharmacology , Coordination Complexes/chemical synthesis , Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Rats , Rats, Sprague-Dawley , Schiff Bases/chemical synthesis , Schiff Bases/chemistry , Schiff Bases/pharmacology
11.
J Food Sci Technol ; 52(12): 7655-68, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26604341

ABSTRACT

The use of chemometrics to analyse infrared spectra to predict pork adulteration in the beef jerky (dendeng) was explored. In the first step, the analysis of pork in the beef jerky formulation was conducted by blending the beef jerky with pork at 5-80 % levels. Then, they were powdered and classified into training set and test set. The second step, the spectra of the two sets was recorded by Fourier Transform Infrared (FTIR) spectroscopy using atenuated total reflection (ATR) cell on the basis of spectral data at frequency region 4000-700 cm(-1). The spectra was categorised into four data sets, i.e. (a) spectra in the whole region as data set 1; (b) spectra in the fingerprint region (1500-600 cm(-1)) as data set 2; (c) spectra in the whole region with treatment as data set 3; and (d) spectra in the fingerprint region with treatment as data set 4. The third step, the chemometric analysis were employed using three class-modelling techniques (i.e. LDA, SIMCA, and SVM) toward the data sets. Finally, the best result of the models towards the data sets on the adulteration analysis of the samples were selected and the best model was compared with the ELISA method. From the chemometric results, the LDA model on the data set 1 was found to be the best model, since it could classify and predict 100 % accuracy of the sample tested. The LDA model was applied toward the real samples of the beef jerky marketed in Jember, and the results showed that the LDA model developed was in good agreement with the ELISA method.

12.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 4): o225-6, 2015 Apr 01.
Article in English | MEDLINE | ID: mdl-26029426

ABSTRACT

In the title compound, C13H16N2O2S, the pyrrolidine ring has a twisted conformation on the central -CH2-CH2- bond. Its mean plane is inclined to the 4-meth-oxy-benzoyl ring by 72.79 (15)°. In the crystal, mol-ecules are linked by N-H⋯O and C-H⋯O hydrogen bonds to the same O-atom acceptor, forming chains along [001]. The chains are linked via slipped parallel π-π inter-actions [inter-centroid distance = 3.7578 (13) Å], forming undulating slabs parallel to (100).

13.
Article in English | MEDLINE | ID: mdl-25748985

ABSTRACT

A novel approach for the determination of Al(3+) from aqueous samples was developed using an optode membrane produced by physical inclusion of Al(3+) selective reagent, which is morin into a plasticized poly(vinyl chloride). The inclusion of Triton X-100 was found to be valuable and useful for enhancing the sorption of Al(3+) ions from liquid phase into the membrane phase, thus increasing the intensity of optode's absorption. The optode showed a linear increase in the absorbance at λ(max)=425 nm over the concentration range of 1.85×10(-6)-1.1×10(-4) mol L(-1) (0.05-3 µg mL(-1)) of Al(3+) ions in aqueous solution after 5 min. The limit of detection was determined to be 1.04×10(-6) mol L(-1) (0.028 µg mL(-1)). The optode developed in the present work was easily prepared and found to be stable, has good mechanical strength, sensitive and reusable. In addition, the optode was tested for Al(3+) determination in lake water, river water and pharmaceutical samples, which the result was satisfactory.


Subject(s)
Aluminum/analysis , Membranes, Artificial , Optics and Photonics , Polymers/chemistry , Flavonoids , Hydrogen-Ion Concentration , Ions , Kinetics , Pharmaceutical Preparations/chemistry , Recycling , Reproducibility of Results , Solutions , Spectrum Analysis , Time Factors , Water Pollutants, Chemical/analysis
14.
Sensors (Basel) ; 14(7): 13186-209, 2014 Jul 22.
Article in English | MEDLINE | ID: mdl-25054632

ABSTRACT

A new silica-gel nanospheres (SiO2NPs) composition was formulated, followed by biochemical surface functionalization to examine its potential in urea biosensor development. The SiO2NPs were basically synthesized based on sol-gel chemistry using a modified Stober method. The SiO2NPs surfaces were modified with amine (-NH2) functional groups for urease immobilization in the presence of glutaric acid (GA) cross-linker. The chromoionophore pH-sensitive dye ETH 5294 was physically adsorbed on the functionalized SiO2NPs as pH transducer. The immobilized urease determined urea concentration reflectometrically based on the colour change of the immobilized chromoionophore as a result of the enzymatic hydrolysis of urea. The pH changes on the biosensor due to the catalytic enzyme reaction of immobilized urease were found to correlate with the urea concentrations over a linear response range of 50-500 mM (R2 = 0.96) with a detection limit of 10 mM urea. The biosensor response time was 9 min with reproducibility of less than 10% relative standard deviation (RSD). This optical urea biosensor did not show interferences by Na+, K+, Mg2+ and NH4+ ions. The biosensor performance has been validated using urine samples in comparison with a non-enzymatic method based on the use of p-dimethylaminobenzaldehyde (DMAB) reagent and demonstrated a good correlation between the two different methods (R2 = 0.996 and regression slope of 1.0307). The SiO2NPs-based reflectometric urea biosensor showed improved dynamic linear response range when compared to other nanoparticle-based optical urea biosensors.


Subject(s)
Biosensing Techniques/instrumentation , Nanoparticles/chemistry , Silica Gel/chemistry , Urea/chemistry , Benzaldehydes/chemistry , Enzymes, Immobilized/chemistry , Humans , Hydrogen-Ion Concentration , Hydrolysis , Limit of Detection , Reproducibility of Results , Transducers , Urease/chemistry
15.
Sensors (Basel) ; 14(2): 2135-49, 2014 Jan 27.
Article in English | MEDLINE | ID: mdl-24473284

ABSTRACT

A simple visual ethanol biosensor based on alcohol oxidase (AOX) immobilised onto polyaniline (PANI) film for halal verification of fermented beverage samples is described. This biosensor responds to ethanol via a colour change from green to blue, due to the enzymatic reaction of ethanol that produces acetaldehyde and hydrogen peroxide, when the latter oxidizes the PANI film. The procedure to obtain this biosensor consists of the immobilization of AOX onto PANI film by adsorption. For the immobilisation, an AOX solution is deposited on the PANI film and left at room temperature until dried (30 min). The biosensor was constructed as a dip stick for visual and simple use. The colour changes of the films have been scanned and analysed using image analysis software (i.e., ImageJ) to study the characteristics of the biosensor's response toward ethanol. The biosensor has a linear response in an ethanol concentration range of 0.01%-0.8%, with a correlation coefficient (r) of 0.996. The limit detection of the biosensor was 0.001%, with reproducibility (RSD) of 1.6% and a life time up to seven weeks when stored at 4 °C. The biosensor provides accurate results for ethanol determination in fermented drinks and was in good agreement with the standard method (gas chromatography) results. Thus, the biosensor could be used as a simple visual method for ethanol determination in fermented beverage samples that can be useful for Muslim community for halal verification.


Subject(s)
Alcohol Oxidoreductases/metabolism , Aniline Compounds/chemistry , Beverages/analysis , Biosensing Techniques , Ethanol/analysis , Food Analysis/methods , Alcohol Oxidoreductases/chemistry , Biosensing Techniques/standards , Calibration , Chromatography, Gas , Color , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Ethanol/standards , Hydrogen-Ion Concentration , Oxidation-Reduction
16.
Talanta ; 116: 776-81, 2013 Nov 15.
Article in English | MEDLINE | ID: mdl-24148473

ABSTRACT

The characteristics of a potentiometric biosensor for the determination of permethrin in treated wood based on immobilised cells of the fungus Lentinus sajor-caju on a potentiometric transducer are reported this paper. The potentiometric biosensor was prepared by immobilisation of the fungus in alginate gel deposited on a pH-sensitive transducer employing a photocurable acrylic matrix. The biosensor gave a good response in detecting permethrin over the range of 1.0-100.0 µM. The slope of the calibration curve was 56.10 mV/decade with detection limit of 1.00 µM. The relative standard deviation for the sensor reproducibility was 4.86%. The response time of the sensor was 5 min at optimum pH 8.0 with 1.00 mg/electrode of fungus L. sajor-caju. The permethrin biosensor performance was compared with the conventional method for permethrin analysis using high performance liquid chromatography (HPLC), and the analytical results agreed well with the HPLC method (at 95% confidence limit). There was no interference from commonly used organophosphorus pesticides such as diazinon, parathion, paraoxon, and methyl parathion.


Subject(s)
Biosensing Techniques/instrumentation , Insecticides/analysis , Lentinula/chemistry , Permethrin/analysis , Wood/chemistry , Acrylates/chemistry , Alginates/chemistry , Calibration , Cells, Immobilized , Electrodes , Gels , Hydrogen-Ion Concentration , Limit of Detection , Potentiometry/methods , Reproducibility of Results
17.
Sensors (Basel) ; 13(8): 10014-26, 2013 Aug 05.
Article in English | MEDLINE | ID: mdl-23921830

ABSTRACT

Chili hotness is very much dependent on the concentration of capsaicin present in the chili fruit. A new biosensor based on a horseradish peroxidase enzyme-capsaicin reaction mediated by ferrocene has been successfully developed for the amperometric determination of chili hotness. The amperometric biosensor is fabricated based on a single-step immobilization of both ferrocene and horseradish peroxidase in a photocurable hydrogel membrane, poly(2-hydroxyethyl methacrylate). With mediation by ferrocene, the biosensor could measure capsaicin concentrations at a potential 0.22 V (vs. Ag/AgCl), which prevented potential interference from other electroactive species in the sample. Thus a good selectivity towards capsaicin was demonstrated. The linear response range of the biosensor towards capsaicin was from 2.5-99.0 µM with detection limit of 1.94 µM. A good relative standard deviation (RSD) for reproducibility of 6.4%-9.9% was obtained. The capsaicin biosensor demonstrated long-term stability for up to seven months. The performance of the biosensor has been validated using a standard method for the analysis of capsaicin based on HPLC.


Subject(s)
Biosensing Techniques/instrumentation , Capsaicin/analysis , Capsaicin/chemistry , Conductometry/instrumentation , Ferrous Compounds/chemistry , Horseradish Peroxidase/chemistry , Taste , Electrodes , Equipment Design , Equipment Failure Analysis , Humans , Metallocenes
18.
Chem Cent J ; 7: 122, 2013.
Article in English | MEDLINE | ID: mdl-23867006

ABSTRACT

BACKGROUND: A novel optical sensor for the rapid and direct determination of permethrin preservatives in treated wood was designed. The optical sensor was fabricated from the immobilisation of 2,6-dichloro-p-benzoquinone-4-chloroimide (Gibbs reagent) in nafion/sol-gel hybrid film and the mode of detection was based on absorption spectrophotometry. Physical entrapment was employed as a method of immobilisation. RESULTS: The sensor gave a linear response range of permethrin between 2.56-383.00 µM with detection limit of 2.5 µM and demonstrated good repeatability with relative standard deviation (RSD) for 10 µM at 5.3%, 100 µM at 2.7%, and 200 µM at 1.8%. The response time of the sensor was 40 s with an optimum response at pH 11. CONCLUSIONS: The sensor was useful for rapid screening of wood or treated wood products before detailed analysis using tedious procedure is performed. The validation study of the optical sensor against standard method HPLC successfully showed that the permethrin sensor tended to overestimate the permethrin concentration determined.

19.
ACM arq. catarin. med ; 42(1)jan.-mar. 2013. ilus
Article in Portuguese | LILACS | ID: lil-673855

ABSTRACT

Objetivo: Relatar um caso de hemotórax espontâneoem paciente hemofílico. Relato de caso: Paciente de 35anos, sexo masculino, admitido no Hospital Regionalde São José por história há 3 dias de dor torácica deinício súbito e evolução progressiva, associada a dispnéia.Diagnóstico de Hemofilia A desde os 2 anos e usoeventual de Fator VIII. À admissão, encontrava-se emregular estado geral, hipocorado, hipotenso, taquicárdico;hematócrito de 16,2% e hemoglobina de 5,5%;radiografia de tórax com derrame pleural ocupando2/3 do hemitórax direito. Tomografia Computadorizada(TC) de tórax: lesão expansiva em mediastino posterior(9,6x4,6x3,9cm). Características líquido pleural: hematócritode 36,5%, hemoglobina 10,6%. Iniciada reposiçãode fator VIII no intervalo de 12 em 12 horas.Durante internação, submetido a TC tórax seriadas. TCtórax 15/05/12: redução derrame pleural, assim comoimagem de coleção hemática para-esofagiana. Consideraçõesfinais: A hemofilia é uma doença ocasionadapela deficiência de um fator dependente da cascata decoagulação, sendo a hemorragia a complicação maisfrequente. Por sua vez, os sangramentos podem ser secundáriosa trauma ou espontâneos. No entanto, hemotóraxespontâneo em paciente hemofílico é um eventoraro e pouco descrito na literatura, havendo apenas 18casos descritos confome revisão bibliográfica.


Objective: To report a case of spontaneoushemothorax in hemophilia patients. Case report:Patient 35 years old, male, admitted to the HospitalRegional de São José history for 3 days of chest pain ofsudden onset and progressive disease, associated withdyspnea. Diagnosis of hemophilia A from 2 years andeventual use of Factor VIII. On admission, the patientwas in good general condition, pallor, hypotension,tachycardia, hematocrit and hemoglobin of 16.2% from5.5%; chest radiograph with pleural effusion occupyingtwo thirds of the right hemithorax. CT chest: masslesion in the posterior mediastinum (9,6 x4, 6x3, 9 cm).Features pleural fluid hematocrit 36.5%, hemoglobin10.6%. Initiated factor VIII replacement within 12 to 12hours. During hospitalization, underwent serial chestCT. 15/05/12 CT chest: reducing pleural effusion, andimage collection for hematic-esophageal. Final Thoughts:Hemophilia is a disease caused by the deficiency of afactor-dependent coagulation cascade, and hemorrhageis the most frequent complication. In turn, the bleedingsmay be secondary to trauma, or spontaneous. However,spontaneous hemothorax in pacinete hemophilia is arare and poorly described in the literature, with only 18cases described confome literature review.

20.
Sensors (Basel) ; 11(9): 8323-38, 2011.
Article in English | MEDLINE | ID: mdl-22164078

ABSTRACT

New acrylic microspheres were synthesised by photopolymerisation where the succinimide functional group was incorporated during the microsphere preparation. An optical biosensor for urea based on reflectance transduction with a large linear response range to urea was successfully developed using this material. The biosensor utilized succinimide-modified acrylic microspheres immobilized with a Nile blue chromoionophore (ETH 5294) for optical detection and urease enzyme was immobilized on the surface of the microspheres via the succinimide groups. No leaching of the enzyme or chromoionophore was observed. Hydrolysis of the urea by urease changes the pH and leads to a color change of the immobilized chromoionophore. When the color change was monitored by reflectance spectrophotometry, the linear response range of the biosensor to urea was from 0.01 to 1,000 mM (R2 = 0.97) with a limit of detection of 9.97 µM. The biosensor response showed good reproducibility (relative standard deviation = 1.43%, n = 5) with no interference by major cations such as Na+, K+, NH4+ and Mg2+. The use of reflectance as a transduction method led to a large linear response range that is better than that of many urea biosensors based on other optical transduction methods.


Subject(s)
Biosensing Techniques , Microspheres , Succinimides/chemistry , Urea/chemistry , Enzymes, Immobilized/chemistry , Hydrogen-Ion Concentration , Microscopy, Electron, Scanning , Reproducibility of Results , Spectroscopy, Fourier Transform Infrared , Urease/chemistry
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