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1.
Electrophoresis ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38576224

RESUMO

This research focuses on the development and validation of a capillary electrophoresis (CE) method for the chiral separation of three H1-antihistamine drugs chlorcyclizine, norchlorcyclizine, and neobenodine using sulfated ß-cyclodextrin (S-ß-CD) as the chiral selector. The study explores various factors influencing the separation efficiency, including CD concentration, organic modifier content, voltage application, and buffer pH. Optimal conditions were identified as a 100 mM phosphate buffer (pH 6.0) with 34 mg mL-1 S-ß-CD and 40% (v/v) methanol. The method demonstrated excellent linearity in calibration curves, with coefficients of determination exceeding 0.99 for each enantiomer. Precision studies revealed good intra- and inter-day precision for migration times and peak areas. The limits of detection and quantification for the analytes were within the ranges of 5.9-11.4 and 18-34.6 µmol L-1, respectively. Overall, the developed CE method offers a robust and precise approach for the chiral separation of H1-antihistamine drugs, holding promise for pharmaceutical applications.

3.
J Mol Recognit ; 35(5): e2953, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35060667

RESUMO

In this study, a sensitive platform was designed for the electrocatalytical oxidation and recognition of ascorbic acid (AA) based on poly(ß-cyclodextrin) modified glassy carbon electrode (p(ß-CD-GCE). Electropolymerization of ß-CD on the surface of GCE was performed on the potential range of -1 to 1.5 V. So, a novel biopolymer was prepared on the surface of GCE towards sensitive recognition of AA in human plasma samples. The developed platform has good sensitivity and accuracy for electrooxidation and detection of AA with lower limit of quantification (LLOQ) of 1 nM and linear range of 1 nM to 100 mM. Moreover, the designed electrochemical sensor was employed for the analysis of AA on human plasma samples with high sensitivity. Based on advantages of p(ß-CD) prepared by electropolymerization procedure (green, fast, homogeny, and efficient eletrocatalytical behaviour), this conductive biopolymer showed excellent analytical behaviour towards electrooxidation of AA. It is expected that the prepared polymeric interface is able to use in the analysis of biological species in clinical samples.


Assuntos
Ácido Ascórbico , Técnicas Eletroquímicas , Materiais Biocompatíveis , Biopolímeros , Técnicas Eletroquímicas/métodos , Humanos , Propilenoglicóis , beta-Ciclodextrinas
4.
Talanta ; 221: 121610, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33076140

RESUMO

Precise detection of important pharmaceuticals with narrow therapeutic index (NTI) is very critical as there is a small window between their effective dose and the doses at which the adverse reactions are very likely to appear. Regarding the fact that various pharmacokinetics will be plausible while considering pharmacogenetic factors and also differences between generic and brand name drugs, accurate detection of NTI will be more important. Current routine analytical techniques suffer from many drawbacks while using novel biosensors can bring up many advantages including fast detection, accuracy, low cost with simple and repeatable measurements. Recently the well-known carbon Nano-allotropes including carbon nanotubes and graphenes have been widely used for development of different Nano-biosensors for a diverse list of analytes because of their great physiochemical features such as high tensile strength, ultra-light weight, unique electronic construction, high thermo-chemical stability, and an appropriate capacity for electron transfer. Because of these exceptional properties, scientists have developed an immense interest in these nanomaterials. In this case, there are important reports to show the effective Nano-carbon based biosensors in the detection of NTI drugs and the present review will critically summarize the available data in this field.


Assuntos
Técnicas Biossensoriais , Grafite , Nanoestruturas , Nanotubos de Carbono , Preparações Farmacêuticas , Índice Terapêutico
5.
Heliyon ; 6(12): e05779, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33376825

RESUMO

Trifluralin is herbicide of the dinitroanilines group in which NO2 molecules are attached to the benzene ring at diverse positions. Trifluralin affects endocrine function and is listed as an endocrine disrupter in the European Union list. Therefore, its determination is so important in health science. In this study, an easy, sensitive and environmentally friendly method has been developed for determination of trifluralin based on its electrochemical oxidation on a three-electrode system designed on the surface of agricultural products using Ag-citrate/GQDs (graphene quantum dots) nano-ink. The sensor was prepared by direct writing on the surface of the samples. The designed electrodes were dried after 24 h at room temperature and used for trifluralin detection. Under optimized experimental conditions, the Ag-citrate/GQDs nano-ink based sensor was exhibited good sensitivity and specificity for trifluralin detection. The obtained linear range using the cyclic voltammetric (CV) technique is between 0.008 to 1 mM and low limit of quantification (LLOQ) was 0.008 mM. Also, the obtained linear range using differential pulse voltammetric (DPV) and square wave voltammetric (SWV) techniques is 0.005-0.04 mM with LLOQ of 0.005 mM. For further validation of the applicability of the proposed method, it was also used for detection of trifluralin on the surface of apple skin.

6.
Small ; 16(40): e2001647, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32790000

RESUMO

Thrombosis is a life-threatening pathological condition in which blood clots form in blood vessels, obstructing or interfering with blood flow. Thrombolytic agents (TAs) are enzymes that can catalyze the conversion of plasminogen to plasmin to dissolve blood clots. The plasmin formed by TAs breaks down fibrin clots into soluble fibrin that finally dissolves thrombi. Several TAs have been developed to treat various thromboembolic diseases, such as pulmonary embolisms, acute myocardial infarction, deep vein thrombosis, and extensive coronary emboli. However, systemic TA administration can trigger non-specific activation that can increase the incidence of bleeding. Moreover, protein-based TAs are rapidly inactivated upon injection resulting in the need for large doses. To overcome these limitations, various types of nanocarriers have been introduced that enhance the pharmacokinetic effects by protecting the TA from the biological environment and targeting the release into coagulation. The nanocarriers show increasing half-life, reducing side effects, and improving overall TA efficacy. In this work, the recent advances in various types of TAs and nanocarriers are thoroughly reviewed. Various types of nanocarriers, including lipid-based, polymer-based, and metal-based nanoparticles are described, for the targeted delivery of TAs. This work also provides insights into issues related to the future of TA development and successful clinical translation.


Assuntos
Infarto do Miocárdio , Trombose , Coagulação Sanguínea , Preparações de Ação Retardada/uso terapêutico , Fibrinolíticos/uso terapêutico , Humanos , Trombose/tratamento farmacológico
7.
Biosens Bioelectron ; 165: 112403, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32729523

RESUMO

Safety and quality of water are significant matters for agriculture, animals and human health. Microcystins, as secondary metabolite of cyanobacteria (blue-green algae) and cyclic heptapeptide cyanotoxin, are one of the main marine toxins in continental aquatic ecosystems. More than 100 microcystins have been identified, of which MC-LR is the most important type due to its high toxicity and common detection in the environment. Climate change is an impressive factor with effects on cyanobacterial blooms as source of microcystins. The presence of this cyanotoxin in freshwater, drinking water, water reservoir supplies and food (vegetable, fish and shellfish) has created a common phenomenon in eutrophic freshwater ecosystems worldwide. International public health organizations have categorized microcystins as a kind of neurotoxin and carcinogen. There are several conventional methods for detection of microcystins. The limitations of traditional methods have encouraged the development of innovative methods for detection of microcystins. In recent years, the developed sensor techniques, with advantages, such as accuracy, reproducibility, portability and low cost, have attracted considerable attention. This review compares the well-known of biosensor types for detection of microcystins with a summary of their analytical performance.


Assuntos
Técnicas Biossensoriais , Microcistinas , Animais , Ecossistema , Humanos , Reprodutibilidade dos Testes , Água
8.
Int J Biol Macromol ; 150: 218-227, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32057844

RESUMO

Haemophilus Influenza leads to respiratory infections such as sinusitis, acute otitis media, pneumonia and bronchitis. In addition, it causes invasive infections such as cellulite, septic arthritis, and meningitis. Therefore, quick and sensitive detection of H. influenza is of great importance in medical microbiology. In this study, a novel DNA-based bioassay was developed to the monitoring of Haemophilus influenza genome in human plasma samples using binding of pDNA with cDNA. DNA hybridization strategy was used to investigation of DNAs binding. For this purpose, silver nanoparticle doped graphene quantum dots inks functionalized by D-penicillamine (Ag NPs-DPA-GQDs) were synthesized and deposited on the surface of glass carbon electrode (GCE). Also, gold nanoparticles functionalized with cysteamine (CysA-AuNPs) were deposited on the surface of the Ag-DPA-GQDs modified GCE. Afterward, thiolated DNA probe was immobilized on the surface of the modified electrode. DNA hybridization was monitored using square wave voltammetry (SWV) technique. Engineered genosensor indicated good performance with high specificity and sensitivity for detection of Haemophilus influenza genome. Under optimal conditions, linear range and low limit of quantitation (LLOQ) were obtained as target concentrations ranging from 1 pM-1 ZM and 1 ZM, respectively. The designed biosensor also showed high capability of discriminating one-base, two-base and three-base mismatched sequences. Also, the prepared genosensor could be easily regenerated and reused to evaluate hybridization process.


Assuntos
Ácidos Nucleicos Livres , DNA Complementar , Genoma Bacteriano , Haemophilus influenzae/genética , Hibridização de Ácido Nucleico/métodos , Técnicas Biossensoriais , Técnicas Eletroquímicas , Humanos , Nanopartículas Metálicas/ultraestrutura , Pontos Quânticos , Reprodutibilidade dos Testes
9.
J Mol Recognit ; 33(2): e2817, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31769086

RESUMO

The rapid and sensitive determination of riboflavin (RF) is important for the treatment of seborrheic and glossitis dermatitis, sunlight sensitivity, mucosal, and skin disorders. In this work, an electrochemical sensor was developed by electrodes modification using poly (chitosan) to sensitive detection of RF in commercial multivitamin. Electrodeposition of chitosan on the surface of glass carbon electrode was performed using cyclic voltammetry technique in the range of -1 to +1 V. The modified electrode surface morphology was characterized using a high-resolution field emission scanning electron microscope. The modified electrode was used as an effective electrical interface for the detection of RF using cyclic, differential pulse, and square wave voltammetry techniques. Finally, the sensor was applied to determine RF in commercial multivitamins. In optimum conditions, the linear range for the standard sample of RF and commercial multivitamins 94 to 333µM and 24.6 to 176µM were obtained, respectively. Low limit of quantification (LLOQ) were obtained as 24.6µM.


Assuntos
Técnicas Biossensoriais , Quitosana/química , Nanocompostos/química , Riboflavina/isolamento & purificação , Carbono/química , Humanos , Limite de Detecção , Riboflavina/química
10.
Enzyme Microb Technol ; 133: 109466, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31874682

RESUMO

Acinetobacter baumannii is a non-motile, gram-negative member of the gamma proteobacteria. A specific and sensitive approach was established for the detection of Acintobacter baumannii via DNA based bio-assay. In this study, gold nano-star was synthesized and used for bio-conjugation with pDNA toward the detection of target sequences. Synthesized probe (5' TTG TGA ACT ATT TAC GTC AGC ATG C3') of Acinetobacter baumannii was found with excellent sensitivity. After the hybridization of pDNA with cDNA, target DNA (5' GCA TGC TGA CGT AAA TAG TTC ACA A 3') was easily measured. According to ultra-sensitivity of the engineered optical DNA-based bio-assay, it is potentially applied in the bacterial detection of the environmental and clinical specimens. Here, the selection of engineered biosensor in the presence of two mismatch sequences was investigated. The results indicated an acceptable choice for DNA-based assays. The low limit of quantification (LLOQ) of genosensor was obtained as 1 fM. The present study is a very important diagnostic examination to recognize Acinetobacter baumannii, which can be a best alternative to the traditional methods.


Assuntos
Acinetobacter baumannii/genética , Bioensaio/métodos , DNA Bacteriano/análise , Ouro/química , Nanopartículas Metálicas/química , Técnicas Biossensoriais/métodos , Limite de Detecção , Sensibilidade e Especificidade
11.
J Pharm Biomed Anal ; 180: 113050, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31881396

RESUMO

A sensitive and specific approach was developed for the determination of Haemophilus influenza using DNA based bio-assay. In this study, citrate capped silver nanoparticle was synthesized and employed for bioconjugation with pDNA toward target sequences detection. In this study, synthesized probe (SH-5'-AAT TTT CCA ACT TTT TCA CCT GCA T-3') of Haemophilus influenza was detected with great sensitivity and selectivity after hybridization with cDNA (5'-ATG CAG GTG AAA AAG TTG GAA AAT T-3'). Regarding to the obtained results, the low limit of quantification (LLOQ) of DNA sample was 1 ZM using 15 µL of probe and 200 µL of Cit/AgNPs. According to ultra-sensitivity of the fabricated optical DNA-based bio-assay, it has potential for bacterial determination both in clinical and environmental specimens. To evaluate the selectivity of developed DNA based biosensor, three mismatch sequences were applied. Finally, the designed genosensor is a significant diagnostic strategy for detection of Haemophilus influenza with great selectivity.


Assuntos
Técnicas Biossensoriais/métodos , Ácido Cítrico/química , Sondas de DNA/química , DNA Bacteriano/análise , Haemophilus influenzae/isolamento & purificação , Nanopartículas Metálicas/química , Prata/química , Bioensaio , Técnicas Biossensoriais/instrumentação , Sondas de DNA/genética , DNA Bacteriano/genética , Haemophilus influenzae/genética , Humanos , Limite de Detecção , Hibridização de Ácido Nucleico , Sensibilidade e Especificidade
12.
Int J Biol Macromol ; 139: 1239-1251, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31400417

RESUMO

Haemophilus influenza (H. influenza) is a gram negative coccobacillus pathogenic microorganism. H. influenza produces beta-lactamases, and it is also able to modify its penicillin-binding proteins, so it has gained resistance to the penicillin family of antibiotics. In this work, a novel sensitive approach was established for the monitoring of H. influenza using DNA based bio-assay. For the first time, specific sequence of thiolated probe of Haemophilus influenza (SH-5'-AAT TTT CCA ACT TTT TCA CCT GCA T-3') was immobilized on the surface of gold (Au) electrode. Square wave voltammetry (SWV) was carried out in toluidine blue (TB) solution for DNA hybridization and targeting of cDNA sequence of Haemophilus influenza. Field scanning electron microscope (FE-SEM) was applied to investigation of the electrode morphology and estimate of particle size. In the optimal conditions, the planned strategy could detect target DNA (5'-ATG CAG GTG AAA AAG TTG GAA AAT T-3') down to 1 ZM with a linear range from 1 µM to 1 ZM. Moreover, engineered geno-assay selectively differentiates the complementary sequence from target sequences with one, double and three base mismatch sequences.


Assuntos
Técnicas Biossensoriais/métodos , DNA/química , Haemophilus/isolamento & purificação , Hibridização de Ácido Nucleico , Técnicas Biossensoriais/economia , Técnicas Biossensoriais/instrumentação , Custos e Análise de Custo , Eletroquímica , Eletrodos , Ouro , Cinética , Limite de Detecção , Modelos Moleculares , Conformação de Ácido Nucleico
13.
Int J Biol Macromol ; 138: 744-754, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31326512

RESUMO

Ovarian cancer is the first and most important cause of malignancy death in women. Mucin 16 or MUC16 protein also known as carcinoma antigen 125 (CA 125) is the most commonly used glycoprotein for early stage diagnosis of ovarian cancer. In this work, a novel paper-based bio-device through hand writing of Ag/RGO (silver nanoparticles/reduced graphene oxide) nano-ink on the flexible paper substrate using pen-on-paper technology was developed. The prepared interface was used to the recognition of CA 125 protein in human biofluid. For this purpose, Ag/rGO nano-ink was synthesized by deposition of Ag nanoparticles onto graphene oxide sheets and the reduction of graphene oxide to rGO simultaneously. Conductivity and resistance of conductive lines were studied after drawing on photographic paper. Subsequently, to prepare a new and unique immuno-device, paper electrode modified by cysteamine caped gold nanoparticles (CysA/Au NPs) using electrochemical techniques. CysA is bonded by sulfur atoms with Au (CysA/Au NPs), and from the amine group with hydroxyl and carboxyl groups of Ag/RGO nano-ink deposited on the surface of paper-based electrodes (CysA/Au NPs/Ag-rGO). Then, anti-CA 125 antibody was immobilized on the electrode surface through Au NPs and CA 125 positively charged amine groups interaction. Atomic force microscopy, Transmission electron microscopy, Field emission scanning electron microscopy, and dynamic light scattering, were performed to identify the engineered immunosensor. Using chronoamperometry technique and under the optimized conditions, the low limit of quantitation (LLOQ) for the proposed immunoassay was recorded as 0.78 U/ml, which this evaluation was performed at highly linear range of 0.78-400 U/ml. The high sensitivity of the electrochemical immunosensor device is indicative of the ability of this immuno-device to detect early stages ovarian cancer.


Assuntos
Biomarcadores Tumorais , Técnicas Biossensoriais , Antígeno Ca-125 , Nanotecnologia , Neoplasias Ovarianas/diagnóstico , Antígeno Ca-125/imunologia , Técnicas Eletroquímicas , Feminino , Humanos , Nanopartículas Metálicas , Técnicas Analíticas Microfluídicas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Int J Biol Macromol ; 132: 748-758, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30940584

RESUMO

Early stage diagnosis of breast cancer by monitoring the proteins in human biological fluids is the best method and the first section toward efficient therapy, delaying metastasis and hindrance mortality. In this study, graphite ink was synthesized and combined with CA 15-3 antibody in order to develop a novel immunosensor for detection of CA 15-3, breast cancer biomarker. Conductivity of bioink was examined by designing various conductive patterns on paper using a rollerball pen. Electrochemical behavior of engineered immunosensor was evaluated through employing sensitive diagnostic technique, DPV (differential pulse voltammetry). Under optimal conditions, the linear concentration range and low limit of quantification (LLOQ) of designed immunosensor was 15-250 U/mL and 15 U/mL, respectively. The process was successfully applied to assay of breast cancer biomarker (CA15-3) in unprocessed human plasma specimens.


Assuntos
Análise Química do Sangue/instrumentação , Neoplasias da Mama/sangue , Imunoensaio/instrumentação , Tinta , Mucina-1/sangue , Nanotecnologia/instrumentação , Papel , Biomarcadores Tumorais/sangue , Eletroquímica , Humanos , Reprodutibilidade dos Testes , Fatores de Tempo
15.
Int J Biol Macromol ; 126: 1255-1265, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30615961

RESUMO

Ovarian cancer (OC) is known to be one of the most lethal malignancies associated with women disease. The CA-125 protein is a repetitive epitope of MUC-16, which plays key role in enhancing the proliferation of cancer cells and inhibiting anticancer immune responses. It is the most widely used biomarker for early stage diagnosis of OC. Also it is the only serum marker which currently used in clinical diagnosis. Monitoring of CA-125 protein in the serum sample is also valuable in evaluating the response of ovarian cancer to treatment. In this research, a novel immunoassay based on immobilization of CA-125 antibody on the biointerface of silver nanoparticles modified graphene quantum dots ink (Ag NPs-GQDs) was successfully designed to recognition of CA-125 protein in a human plasma sample. The supplied immunoassay presents the proper ability to detect and determine the amount of CA-125 biomarker in low concentrations of CA-125 biomarker. The proposed immunosensor was employed for the detection of CA-125 using differential pulse voltammetry (DPVs) and square wave voltammetry (SWVs) techniques. The proposed interface leads to enhancement of accessible surface area for immobilizing a high amount of anti-CA-125 antibody, increasing electrical conductivity, boosting stability, catalytic properties and biocompatibility. Under the optimized operating conditions, the low limit of quantitation (LLOQ) for the proposed immunosensor was recorded as 0.01 U/mL, which this evaluation was performed at highly linear range of 0.01-400 U/mL. The proposed immunoassay was successfully applied for the monitoring of CA-125 in unprocessed human plasma samples.


Assuntos
Bioensaio/métodos , Antígeno Ca-125/sangue , Detecção Precoce de Câncer/métodos , Epitopos/química , Imunoensaio/métodos , Nanopartículas/química , Neoplasias Ovarianas/diagnóstico , Prata/química , Biomarcadores Tumorais/sangue , Técnicas Biossensoriais , Condutividade Elétrica , Técnicas Eletroquímicas , Feminino , Humanos , Tinta , Nanopartículas/ultraestrutura , Neoplasias Ovarianas/sangue , Espectrometria por Raios X
16.
Mikrochim Acta ; 185(12): 568, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30506320

RESUMO

This review (with 145 refs.) summarizes the progress made in the past years in the field of nanomaterial based rapid detection of hepatitis viruses. Following an introduction into the field (with subsection on the significance of hepatitis and on fundamentals of biosensors), conventional methods for detection of hepatitis are discussed, along with their limitationss. The next section covers electrochemical sensors, with subsections on voltammetric, amperometric, potentiometric, impedimetric and conductometric biosensors. A further large section covers optical methods, with subsections on methods based on fluorescence, photometry, surface plasmon resonance, surface-enhanced Raman scattering and chemiluminescence. A concluding section discusses current challenges and gives an outlook on potential future developments. Graphical abstract A schematic illustration of biosensor components applied for detection of hepatitis viruses.


Assuntos
Técnicas Biossensoriais/métodos , Eletroquímica/métodos , Hepatite/diagnóstico , Nanoestruturas , Fenômenos Ópticos , Humanos
17.
J Control Release ; 266: 166-186, 2017 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-28941992

RESUMO

Cancer stem cells (CSCs) are one of the most important origins of cancer progression and metastasis. CSCs have unique self-renewal properties and diverse cell membrane receptors that induced the resistance to the conventional chemotherapeutic agents. Therefore, the therapeutic removal of CSCs could result in the cancer cure with lack of recurrence and metastasis. In this regard, targeting CSCs in accordance to their specific biomarkers is a talented attitude in cancer therapy. Various CSCs surface biomarkers have been described, which some of them exhibited similarities on different cancer cell types, while the others are cancer specific and have just been reported on one or a few types of cancers. In this review, the importance of CSCs in cancer development and therapeutic response has been stated. Different CSCs cluster of differentiation (CD) biomarkers and their specific function and applications in the treatment of cancers have been discussed, Special attention has been made on targeted nano-delivery systems. In this regard, several examples have been illustrated concerning specific natural and artificial ligands against CSCs CD biomarkers that could be decorated on various nanoparticulated drug delivery systems to enhance therapeutic index of chemotherapeutic agents or anticancer gene therapy. The outlook of CSCs biomarkers discovery and therapeutic/diagnostic applications was discussed.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas/administração & dosagem , Células-Tronco Neoplásicas , Animais , Antineoplásicos/administração & dosagem , Biomarcadores Tumorais , Diferenciação Celular , Humanos
18.
Enzyme Microb Technol ; 105: 64-76, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28756863

RESUMO

In this work, physical adsorption was used for immobilization of proline dehydrogenase onto a magnetic mesoporous silica nanomaterial. The immobilization and electrocatalytical activity of proline dehydrogenase entrapped in a magnetic mesoporous silica nanomaterial was studied using cyclic voltammetry, differential pulse voltammetry, and square wave voltammetry. The magnetic mesoporous silica networks having a high surface area (362m2g-1) exhibited excellent properties for entrapment of proline dehydrogenase. The applied approach led to better resistance to temperature and pH inactivation in comparison to the free enzyme. The electrocatalytic current response of proline dehydrogenase entrapped in a magnetic mesoporous silica nanomaterial toward oxidation of L-proline was maintained in the analytical solution temperature up to 70°C. The entrapped proline dehydrogenase was casted onto a polycysteine-modified glassy carbon electrode. The electrode was evaluated as an electrochemical biosensor for electrooxidation and determination of L-proline in phosphate buffer solution. A cyclic voltammetry study indicated that the oxidation process of proline is irreversible and is diffusion controlled. The electrochemical behavior was further exploited as a sensitive detection scheme for L-proline determination by differential-pulse voltammetry. Under optimized conditions, the concentration range and detection limit were 0.01-0.15µM and 0.006µM, respectively. The method was applied to the assay of L-proline in whole blood and normal and malignant cell line lysates (normal cell (L929); gastric cancer cell-CAT 3, colon cancer cell-HCT, colon cancer cell-SW, and breast cancer cell-MCF7).


Assuntos
Técnicas Biossensoriais/métodos , Enzimas Imobilizadas/metabolismo , Prolina Oxidase/metabolismo , Prolina/análise , Animais , Linhagem Celular , Linhagem Celular Tumoral , Técnicas Eletroquímicas , Humanos , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestrutura , Camundongos , Microscopia Eletrônica de Varredura , Prolina/sangue , Dióxido de Silício
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