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  1 / 1990 MEDLINE  
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[PMID]:29254588
[Au] Autor:Petoukhova A; Rüssel I; Nijst-Brouwers J; van Wingerden K; van Egmond J; Jacobs D; Marinelli A; van der Sijp J; Koper P; Struikmans H
[Ad] Endereço:Haaglanden Medical Center, Department of Medical Physics, Leidschendam, The Netherlands. Electronic address: a.petoukhova@haaglandenmc.nl.
[Ti] Título:In vivo dosimetry with MOSFETs and GAFCHROMIC films during electron IORT for Accelerated Partial Breast Irradiation.
[So] Source:Phys Med;44:26-33, 2017 Dec.
[Is] ISSN:1724-191X
[Cp] País de publicação:Italy
[La] Idioma:eng
[Ab] Resumo:PURPOSE: The purpose of this study was to compare the delivered dose to the expected intraoperative radiation therapy (IORT) dose with in vivo dosimetry. For IORT using electrons in accelerated partial breast irradiation, this is especially relevant since a high dose is delivered in a single fraction. METHODS: For 47 of breast cancer patients, in vivo dosimetry was performed with MOSFETs and/or GAFCHROMIC EBT2 films. A total dose of 23.33 Gy at d was given directly after completing the lumpectomy procedure with electron beams generated with an IORT dedicated mobile accelerator. A protection disk was used to shield the thoracic wall. RESULTS: The results of in vivo MOSFET dosimetry for 27 patients and GAFROMIC film dosimetry for 20 patients were analysed. The entry dose for the breast tissue, measured with MOSFETs, (mean value 22.3 Gy, SD 3.4%) agreed within 1.7% with the expected dose (mean value 21.9 Gy). The dose in breast tissue, measured with GAFCHROMIC films (mean value 23.50 Gy) was on average within 0.7% (SD = 3.7%, range -5.5% to 5.6%) of the prescribed dose of 23.33 Gy. CONCLUSIONS: The dose measured with MOSFETs and GAFROMIC EBT2 films agreed well with the expected dose. For both methods, the dose to the thoracic wall, lungs and heart for left sided patents was lower than 2.5 Gy even when 12 MeV was applied. The positioning time of GAFCHROMIC films is negligible and based on our results we recommend its use as a standard tool for patient quality assurance during breast cancer IORT.
[Mh] Termos MeSH primário: Neoplasias da Mama/radioterapia
Elétrons/uso terapêutico
Dosimetria Fotográfica/instrumentação
Metais/química
Óxidos/química
Dosímetros de Radiação
Transistores Eletrônicos
[Mh] Termos MeSH secundário: Neoplasias da Mama/cirurgia
Calibragem
Seres Humanos
Período Intraoperatório
Meia-Idade
Aceleradores de Partículas
Dosagem Radioterapêutica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Metals); 0 (Oxides)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180130
[Lr] Data última revisão:
180130
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171220
[St] Status:MEDLINE


  2 / 1990 MEDLINE  
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[PMID]:29215256
[Au] Autor:Ivanov YD; Malsagova KA; Pleshakova TO; Shumov ID; Kaysheva AL; Popov VP; Naumova OV; Fomin BI; Nasimov DA; Latyshev AV; Aseev AL; Tatur VY; Ivanova ND; Konovalova GM; Archakov AI
[Ti] Título:[Registration of the protein in the serum with a field-effect nanotransistor biosensor].
[So] Source:Patol Fiziol Eksp Ter;60(1):94-8, 2016 Jan-Mar.
[Is] ISSN:0031-2991
[Cp] País de publicação:Russia (Federation)
[La] Idioma:rus
[Ab] Resumo:A method for detection of cancer-associated protein D-NFATc1 in serum using nanowire (NW) biosensor based on field-effect nanotransistor is developed. Field-effect nanotransistor was fabricated on the basis of «silicon-on-insulator¼ structures. For the biospecific detection of target protein, the NW surface was modified with aptamers against the target protein. Using the 3 um-NW enabled to obtain stable source-drain characteristics and to register D-NFATc1 in serum at concentration of 2.5 x 1014 M in the mode of drain-source current vs. gate voltage characteristics measurements. Data collection in the mode of drain-source current vs. gate voltage characteristics measurements was carried out with the use of high-speed data collection system running TURBO NBS software.
[Mh] Termos MeSH primário: Técnicas Biossensoriais
Fatores de Transcrição NFATC/sangue
Nanofios
Proteínas de Neoplasias/sangue
Software
Transistores Eletrônicos
[Mh] Termos MeSH secundário: Técnicas Biossensoriais/instrumentação
Técnicas Biossensoriais/métodos
Seres Humanos
Sensibilidade e Especificidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (NFATC Transcription Factors); 0 (NFATC1 protein, human); 0 (Neoplasm Proteins)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171221
[Lr] Data última revisão:
171221
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171208
[St] Status:MEDLINE


  3 / 1990 MEDLINE  
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[PMID]:28721039
[Au] Autor:Bao Z; Sun J; Zhao X; Li Z; Cui S; Meng Q; Zhang Y; Wang T; Jiang Y
[Ad] Endereço:Department of Gastrointestinal Surgery, Lianyungang First People's Hospital, Affiliated Hospital of the Clinical Medical School of Nanjing Medical University, Lianyungang.
[Ti] Título:Top-down nanofabrication of silicon nanoribbon field effect transistor (Si-NR FET) for carcinoembryonic antigen detection.
[So] Source:Int J Nanomedicine;12:4623-4631, 2017.
[Is] ISSN:1178-2013
[Cp] País de publicação:New Zealand
[La] Idioma:eng
[Ab] Resumo:Sensitive and quantitative detection of tumor markers is highly required in the clinic for cancer diagnosis and consequent treatment. A field-effect transistor-based (FET-based) nanobiosensor emerges with characteristics of being label-free, real-time, having high sensitivity, and providing direct electrical readout for detection of biomarkers. In this paper, a top-down approach is proposed and implemented to fulfill a novel silicon nano-ribbon FET, which acts as biomarker sensor for future clinical application. Compared with the bottom-up approach, a top-down fabrication approach can confine width and length of the silicon FET precisely to control its electrical properties. The silicon nanoribbon (Si-NR) transistor is fabricated on a Silicon-on-Insulator (SOI) substrate by a top-down approach with complementary metal oxide semiconductor (CMOS)-compatible technology. After the preparation, the surface of Si-NR is functionalized with 3-aminopropyltriethoxysilane (APTES). Glutaraldehyde is utilized to bind the amino terminals of APTES and antibody on the surface. Finally, a microfluidic channel is integrated on the top of the device, acting as a flowing channel for the carcinoembryonic antigen (CEA) solution. The Si-NR FET is 120 nm in width and 25 nm in height, with ambipolar electrical characteristics. A logarithmic relationship between the changing ratio of the current and the CEA concentration is measured in the range of 0.1-100 ng/mL. The sensitivity of detection is measured as 10 pg/mL. The top-down fabricated biochip shows feasibility in direct detecting of CEA with the benefits of real-time, low cost, and high sensitivity as a promising biosensor for tumor early diagnosis.
[Mh] Termos MeSH primário: Técnicas Biossensoriais/instrumentação
Antígeno Carcinoembrionário/análise
Nanotecnologia/métodos
Nanotubos de Carbono/química
[Mh] Termos MeSH secundário: Biomarcadores Tumorais/análise
Desenho de Equipamento
Seres Humanos
Dispositivos Lab-On-A-Chip
Propilaminas/química
Sensibilidade e Especificidade
Silanos/química
Silício/química
Transistores Eletrônicos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biomarkers, Tumor); 0 (Carcinoembryonic Antigen); 0 (Nanotubes, Carbon); 0 (Propylamines); 0 (Silanes); L8S6UBW552 (amino-propyl-triethoxysilane); Z4152N8IUI (Silicon)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171010
[Lr] Data última revisão:
171010
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170720
[St] Status:MEDLINE
[do] DOI:10.2147/IJN.S135985


  4 / 1990 MEDLINE  
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[PMID]:28704926
[Au] Autor:Islam K; Suhail A; Pan G
[Ad] Endereço:Wolfson Nanomaterials and Devices Laboratory, School of Computing, Electronics and Mathematics, Faculty of Science and Engineering, University of Plymouth, Drake Circus, Plymouth PL4 8AA, UK. kamrul.islam@plymouth.ac.uk.
[Ti] Título:A Label-Free and Ultrasensitive Immunosensor for Detection of Human Chorionic Gonadotrophin Based on Graphene FETs.
[So] Source:Biosensors (Basel);7(3), 2017 Jul 12.
[Is] ISSN:2079-6374
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:We report on a label-free immunosensor based on graphene field effect transistors (G-FETs) for the ultrasensitive detection of Human Chorionic Gonadotrophin (hCG), as an indicator of pregnancy and related disorders, such as actopic pregnancy, choriocarcinoma and orchic teratoma. Pyrene based bioactive ester was non-covalently anchored onto the graphene channel in order to retain the sp² lattice. The G-FET transfer characteristics showed repeatable and reliable responses in all surface modifying steps using a direct current (DC) readout system. The hCG concentration gradient showed a detection limit of ~1 pg·mL . The proposed method facilitates the cost-effective and viable production of graphene point-of-care devices for clinical diagnosis.
[Mh] Termos MeSH primário: Técnicas Biossensoriais
Gonadotropina Coriônica/isolamento & purificação
Grafite/química
[Mh] Termos MeSH secundário: Feminino
Ouro/química
Seres Humanos
Gravidez
Transistores Eletrônicos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chorionic Gonadotropin); 7440-57-5 (Gold); 7782-42-5 (Graphite)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:171001
[Lr] Data última revisão:
171001
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170715
[St] Status:MEDLINE


  5 / 1990 MEDLINE  
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[PMID]:28358305
[Au] Autor:Takshi A; Yaghoubi H; Wang J; Jun D; Beatty JT
[Ad] Endereço:Department of Electrical Engineering, University of South Florida (USF), Tampa, FL 33620, USA. atakshi@usf.edu.
[Ti] Título:Electrochemical Field-Effect Transistor Utilization to Study the Coupling Success Rate of Photosynthetic Protein Complexes to Cytochrome c.
[So] Source:Biosensors (Basel);7(2), 2017 Mar 30.
[Is] ISSN:2079-6374
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Due to the high internal quantum efficiency, reaction center (RC) proteins from photosynthetic organisms have been studied in various bio-photoelectrochemical devices for solar energy harvesting. In vivo, RC and cytochrome (cyt ; a component of the biological electron transport chain) can form a cocomplex via interprotein docking. This mechanism can be used in vitro for efficient electron transfer from an electrode to the RC in a bio-photoelectrochemical device. Hence, the success rate in coupling RCs to cyt is of great importance for practical applications in the future. In this work, we use an electrochemical transistor to study the binding of the RC to cytochrome. The shift in the transistor threshold voltage was measured in the dark and under illumination to estimate the density of cytochrome and coupled RCs on the gate of the transistor. The results show that ~33% of the cyt s on the transistor gate were able to effectively couple with RCs. Due to the high sensitivity of the transistor, the approach can be used to make photosensors for detecting low light intensities.
[Mh] Termos MeSH primário: Citocromos c/metabolismo
Técnicas Eletroquímicas
Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo
Transistores Eletrônicos
[Mh] Termos MeSH secundário: Citocromos c/química
Complexo de Proteínas do Centro de Reação Fotossintética/química
Ligação Proteica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Photosynthetic Reaction Center Complex Proteins); 9007-43-6 (Cytochromes c)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170714
[Lr] Data última revisão:
170714
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170331
[St] Status:MEDLINE


  6 / 1990 MEDLINE  
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[PMID]:28219029
[Au] Autor:Piro B; Wang D; Benaoudia D; Tibaldi A; Anquetin G; Noël V; Reisberg S; Mattana G; Jackson B
[Ad] Endereço:Univ. Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR 7086 CNRS, 15 rue J-A de Baïf, 75205 Paris Cedex 13, France. Electronic address: piro@univ-paris-diderot.fr.
[Ti] Título:Versatile transduction scheme based on electrolyte-gated organic field-effect transistor used as immunoassay readout system.
[So] Source:Biosens Bioelectron;92:215-220, 2017 Jun 15.
[Is] ISSN:1873-4235
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:We report on an innovative heterogeneous bisphenol A (BPA) immunoassay based on an electrolyte-gated organic field-effect transistor whose organic semiconductor is poly(2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene) co-crystallized with an alkyl derivative of bisphenol A. A decrease of the transistor output current is first observed upon antibody specific binding onto the organic semiconductor. Upon bisphenol A addition, the competitive dissociation of the antibody from the semiconductor surface leads to an opposite increase of the output current. We present here a proof-of-concept for bisphenol A detection; the device could be readily adapted to other small organic molecules of interest and is a promising tool for simple, low-cost, portable and easy-to-use biosensors.
[Mh] Termos MeSH primário: Compostos Benzidrílicos/análise
Técnicas Biossensoriais/instrumentação
Eletrólitos/química
Fenóis/análise
Transistores Eletrônicos
Poluentes Químicos da Água/análise
[Mh] Termos MeSH secundário: Anticorpos Imobilizados/química
Técnicas Biossensoriais/economia
Desenho de Equipamento
Imunoensaio
Tiofenos/química
Transistores Eletrônicos/economia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Immobilized); 0 (Benzhydryl Compounds); 0 (Electrolytes); 0 (Phenols); 0 (Thiophenes); 0 (Water Pollutants, Chemical); MLT3645I99 (bisphenol A)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170323
[Lr] Data última revisão:
170323
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170221
[St] Status:MEDLINE


  7 / 1990 MEDLINE  
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[PMID]:28178236
[Au] Autor:Adinolfi V; Sargent EH
[Ad] Endereço:Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada.
[Ti] Título:Photovoltage field-effect transistors.
[So] Source:Nature;542(7641):324-327, 2017 02 16.
[Is] ISSN:1476-4687
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The detection of infrared radiation enables night vision, health monitoring, optical communications and three-dimensional object recognition. Silicon is widely used in modern electronics, but its electronic bandgap prevents the detection of light at wavelengths longer than about 1,100 nanometres. It is therefore of interest to extend the performance of silicon photodetectors into the infrared spectrum, beyond the bandgap of silicon. Here we demonstrate a photovoltage field-effect transistor that uses silicon for charge transport, but is also sensitive to infrared light owing to the use of a quantum dot light absorber. The photovoltage generated at the interface between the silicon and the quantum dot, combined with the high transconductance provided by the silicon device, leads to high gain (more than 10 electrons per photon at 1,500 nanometres), fast time response (less than 10 microseconds) and a widely tunable spectral response. Our photovoltage field-effect transistor has a responsivity that is five orders of magnitude higher at a wavelength of 1,500 nanometres than that of previous infrared-sensitized silicon detectors. The sensitization is achieved using a room-temperature solution process and does not rely on traditional high-temperature epitaxial growth of semiconductors (such as is used for germanium and III-V semiconductors). Our results show that colloidal quantum dots can be used as an efficient platform for silicon-based infrared detection, competitive with state-of-the-art epitaxial semiconductors.
[Mh] Termos MeSH primário: Raios Infravermelhos
Pontos Quânticos
Silício
Transistores Eletrônicos
[Mh] Termos MeSH secundário: Coloides
Elétrons
Fótons
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Colloids); Z4152N8IUI (Silicon)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170814
[Lr] Data última revisão:
170814
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170209
[St] Status:MEDLINE
[do] DOI:10.1038/nature21050


  8 / 1990 MEDLINE  
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[PMID]:27984705
[Au] Autor:Lei YM; Xiao MM; Li YT; Xu L; Zhang H; Zhang ZY; Zhang GJ
[Ad] Endereço:School of Laboratory Medicine, Hubei University of Chinese Medicine, 1 Huangjia Lake West Road, Wuhan 430065, PR China; School of Information Engineering, Wuhan Technology and Business University, 1 Huangjia Lake West Road, Wuhan 430065, PR China.
[Ti] Título:Detection of heart failure-related biomarker in whole blood with graphene field effect transistor biosensor.
[So] Source:Biosens Bioelectron;91:1-7, 2017 May 15.
[Is] ISSN:1873-4235
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Since brain natriuretic peptide (BNP) has become internationally recognized biomarkers in the diagnosis and prognosis of heart failure (HF), it is highly desirable to search for a novel sensing tool for detecting the patient's BNP level at the early stage. Here we report a platinum nanoparticles (PtNPs)-decorated reduced graphene oxide (rGO) field effect transistor (FET) biosensor coupled with a microfilter system for label-free and highly sensitive detection of BNP in whole blood. The PtNPs-decorated rGO FET sensor was obtained by drop-casting rGO onto the pre-fabricated FET chip and subsequently assembling PtNPs on the graphene surface. After anti-BNP was bound to the PtNPs surface, BNP was successfully detected by the anti-BNP immobilized FET biosensor. It was found that the developed FET biosensor was able to achieve a low detection limitation of 100fM. Moreover, BNP was successfully detected in human whole blood sample treated by a custom-made microfilter, suggesting the sensor's capability of working in a complex sample matrix. The developed FET biosensor provides a new sensing platform for protein detection, showing its potential applications in clinic sample.
[Mh] Termos MeSH primário: Técnicas Biossensoriais/instrumentação
Grafite/química
Insuficiência Cardíaca/sangue
Nanopartículas Metálicas/química
Peptídeo Natriurético Encefálico/sangue
Platina/química
Transistores Eletrônicos
[Mh] Termos MeSH secundário: Biomarcadores/sangue
Desenho de Equipamento
Seres Humanos
Limite de Detecção
Nanopartículas Metálicas/ultraestrutura
Óxidos/química
[Pt] Tipo de publicação:EVALUATION STUDIES; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biomarkers); 0 (Oxides); 114471-18-0 (Natriuretic Peptide, Brain); 49DFR088MY (Platinum); 7782-42-5 (Graphite)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170531
[Lr] Data última revisão:
170531
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161217
[St] Status:MEDLINE


  9 / 1990 MEDLINE  
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[PMID]:27977067
[Au] Autor:Bi D; Luo J; Zhang F; Magrez A; Athanasopoulou EN; Hagfeldt A; Grätzel M
[Ad] Endereço:Laboratory of Photonics and Interfaces, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Station 6, CH-1015, Lausanne, Switzerland.
[Ti] Título:Morphology Engineering: A Route to Highly Reproducible and High Efficiency Perovskite Solar Cells.
[So] Source:ChemSusChem;10(7):1624-1630, 2017 Apr 10.
[Is] ISSN:1864-564X
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Despite the rapid increase in the performance of perovskite solar cells (PSC), they still suffer from low lab-to-lab or people-to-people reproducibility. Aiming for a universal condition to high-performance devices, we investigated the morphology evolution of a composite perovskite by tuning annealing temperature and precursor concentration of the perovskite film. Here, we introduce thermal annealing as a powerful tool to generate a well-controlled excess of PbI in the perovskite formulation and show that this benefits the photovoltaic performance. We demonstrated the correlation between the film microstructure and electronic property and device performance. An optimized average grain size/thickness aspect ratio of the perovskite crystallite is identified, which brings about a highly reproducible power conversion efficiency (PCE) of 19.5 %, with a certified value of 19.08 %. Negligible hysteresis and outstanding morphology stability are observed with these devices. These findings lay the foundation for further boosting the PCE of PSC and can be very instructive for fabrication of high-quality perovskite films for a variety of applications, such as light-emitting diodes, field-effect transistors, and photodetectors.
[Mh] Termos MeSH primário: Compostos de Cálcio/química
Fontes de Energia Elétrica
Engenharia
Óxidos/química
Energia Solar
Titânio/química
[Mh] Termos MeSH secundário: Temperatura Ambiente
Transistores Eletrônicos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Calcium Compounds); 0 (Oxides); 12194-71-7 (perovskite); D1JT611TNE (Titanium)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170606
[Lr] Data última revisão:
170606
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161216
[St] Status:MEDLINE
[do] DOI:10.1002/cssc.201601387


  10 / 1990 MEDLINE  
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[PMID]:27956364
[Au] Autor:Imaizumi Y; Goda T; Schaffhauser DF; Okada JI; Matsumoto A; Miyahara Y
[Ad] Endereço:Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University (TMDU), 2-3-10 Kanda-Surugadai, Chiyoda, Tokyo 101-0062 Japan.
[Ti] Título:Proton-sensing transistor systems for detecting ion leakage from plasma membranes under chemical stimuli.
[So] Source:Acta Biomater;50:502-509, 2017 Mar 01.
[Is] ISSN:1878-7568
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The membrane integrity of live cells is routinely evaluated for cytotoxicity induced by chemical or physical stimuli. Recent progress in bioengineering means that high-quality toxicity validation is required. Here, we report a pH-sensitive transistor system developed for the continuous monitoring of ion leakage from cell membranes upon challenge by toxic compounds. Temporal changes in pH were generated with high reproducibility via periodic flushing of HepG2 cells on a gate insulator of a proton-sensitive field-effect transistor with isotonic buffer solutions with/without NH Cl. The pH transients at the point of NH Cl addition/withdrawal originated from the free permeation of NH across the semi-permeable plasma membranes, and the proton sponge effect produced by the ammonia equilibrium. Irreversible attenuation of the pH transient was observed when the cells were subjected to a membrane-toxic reagent. Experiments and simulations proved that the decrease in the pH transient was proportional to the area of the ion-permeable pores on the damaged plasma membranes. The pH signal was correlated with the degree of hemolysis produced by the model reagents. The pH assay was sensitive to the formation of molecularly sized pores that were otherwise not measurable via detection of the leakage of hemoglobin, because the hydrodynamic radius of hemoglobin was greater than 3.1nm in the hemolysis assay. The pH transient was not disturbed by inherent ion-transporter activity. The ISFET assay was applied to a wide variety of cell types. The system presented here is fast, sensitive, practical and scalable, and will be useful for validating cytotoxins and nanomaterials. STATEMENT OF SIGNIFICANCE: The plasma membrane toxicity and hemolysis are widely and routinely evaluated in biomaterials science and biomedical engineering. Despite the recent development of a variety of methods/materials for efficient gene/drug delivery systems to the cytosol, the methodologies for safety validation remain unchanged in many years while leaving some major issues such as sensitivity, accuracy, and fast response. The paper describes a new way of measuring the plasma membrane leakage in real time upon challenge by toxic reagents using a solid-state transistor that is sensitive to proton as the smallest indicator. Our system was reliable and was correlated to the results from hemolysis assay with advanced features in sensitivity, fast response, and wide applicability to chemical species. The downsizing and integration features of semiconductor fabrication technologies may realize cytotoxicity assays at the single-cell level in multi-parallel.
[Mh] Termos MeSH primário: Membrana Celular/química
Prótons
Transistores Eletrônicos
[Mh] Termos MeSH secundário: Amônia/farmacologia
Animais
Linhagem Celular
Seres Humanos
Concentração de Íons de Hidrogênio
Íons
Ovinos
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ions); 0 (Protons); 7664-41-7 (Ammonia)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171107
[Lr] Data última revisão:
171107
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161214
[St] Status:MEDLINE



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