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The effects of glyphosate salts and volatility-reducing agents (VRA) on dicamba volatilityGlenn, Nicole 09 December 2022 (has links) (PDF)
Dicamba is often tank mixed with glyphosate to increase herbicidal efficacy but may contribute to off-target movement (OTM). In recent years, volatilization has become problematic for dicamba-containing herbicides, resulting in increased regulatory requirements necessitating the use of volatility-reducing agents (VRA) for application. Research was conducted in 2021 and 2022 using low tunnels in a field environment and humidomes in a greenhouse environment to further assess how glyphosate salts and VRAs affect dicamba volatility. Our data indicate that the inclusion of glyphosate to dicamba can increase dicamba volatility, depending on the glyphosate salt used. The inclusion of the evaluated VRAs will decrease dicamba volatility when applied to a tank mixture of dicamba plus potassium salt of glyphosate.
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Modified soy protein based adhesives and their physicochemical propertiesQi, Guangyan January 1900 (has links)
Doctor of Philosophy / Department of Grain Science and Industry / Xiuzhi Susan Sun / Soy protein is one of the most promising bio-degradable adhesives, with great
potential as alternatives synthetic petroleum based adhesives for wood composite industries.
However, its intrinsic drawbacks such as low water resistance, high viscosity, and short shelf
life still limit its broad application. In this research, soy protein was further modified and
characterized to improve adhesion properties, flow-ability, water resistance, and long shelf
life, which could facilitate the industrialization of soy protein based adhesives.
In this study, we exploited the in situ sodium bisulfite (NaHSO3) modification on soy
protein in soy flour-water extracts, and then the modified soy protein was obtained through
acid precipitation. First, different concentrations of NaHSO3 were used to modify soy flour
slurry, then glycinin-rich and β-conglycinin-rich fractions were precipitated at pH 5.4 (SP 5.4)
and pH 4.5 (SP 4.5), respectively. Unmodified sample SP 5.4 and SP 4.5 showed clay-like
properties and viscoelastic properties, respectively; whereas with addition of NaHSO3 in
range of 2-8 g/L, both SP 5.4 and SP 4.5 had the viscous cohesive phase with good handability
and flow-ability. The overall adhesion performance of SP 4.5 was better than SP 5.4;
the wet strength of these two fractions was in the range of 2.5-3.2 MPa compared to 1.6 MPa
of control soy protein isolate.
Then soy protein with various β-conglycinin/glycinin (7S/11S) ratios were extracted
from soy flour slurry and characterized for adhesion properties based on the different
solubility of 7S and 11S globulins. Seven glycinin-rich soy protein fractions and six β-
conglycinin-rich soy protein fractions were obtained. According to the morphology, viscosity,
and particle size results, we proposed that proper protein-protein interaction, hydration
capacity (glycinin-rich fractions), and certain 7S/11S ratios (β-conglycinin-rich fractions) in
modified soy protein are crucial to continuous protein phase formation. The viscous cohesive
samples were stable for up to several months without phase separation at room temperature,
with the wet adhesion strength of 2.0-2.8 MPa.
The soy protein modified with NaHSO3 showed good compatibility with commercial
glues applied on plywood and paper labeling fields. The modified soy protein made some
functional groups, carboxylic (-COOH), hydroxyl (-OH) and amino groups (-NH2) available,
which cross-linked with hydroxymethyl groups (-CH2-OH) from urea formaldehyde (UF)
wood glue. The modified soy protein (MSP) with pH 4.8 also acted as an acidic catalyst for
the self-polymerization of UF based resin. The wet adhesion strength of MSP/UF blends
(40/60) was 6.4 MPa with 100% wood cohesive failure, as compared to 4.66 MPa of UF. As
to the paper labeling application, peel strength of MSP on glass substrate increased rapidly,
with curing time much shorter than commercial polyvinyl acetate based adhesives (PVAc).
And the MSP/ PVAc blends showed shorter curing time, higher water resistance and lower
viscosity than pure PVAc.
Chemical modification could also enhance the adhesion strength of MSP. 2-octen-1-
ylsuccinic anhydride (OSA) was proved to be grafted on soy protein through reaction
between amine, hydroxyl groups of protein and anhydride groups. The oily nature and
hydrophobic long alkyl chains of OSA mainly contributed to the significant water resistance
improvement of MSP.
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Systém pro snížení NOx / NOx Reduction SystemKarafa, Pavel January 2017 (has links)
This diploma thesis deals with the issue of nitrogen oxides emissions in exhaust gases and possibilities of their reduction. The task of the thesis was analysis of systems for NOX reduction by contemporary diesel engines, design and construction of NOX reduction device for given diesel engine, then verify functionality of this system compiled from commercially available components. In the last part of thesis available measurements will be made with an analysis of achieved results.
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Avaliação das propriedades de oxirredução e reforço mecânico de materiais híbridos baseados em nanotubos de carbono sobre suportes microestruturados / Redox and mechanical reinforcement properties of carbon nanotubes composites grown on the surface of microstructured materialsMacedo, Nadia Guerra 26 October 2015 (has links)
Nanotubos de carbono (NTC) apresentam superlativas propriedades físico-químicas. Por essa razão, têm sido tema de diversas pesquisas, teóricas e experimentais, para sua aplicação em compósitos que transmitam a outros materiais de interesse, as suas propriedades intrínsecas superiores. Materiais híbridos apresentam propriedades que são diferentes das de seus componentes individuais, sendo resultado das interações e das quantidades de seus componentes. O presente trabalho teve como objetivo a investigação das propriedades híbridas que podem surgir quando nanotubos de carbono são crescidos verticalmente sobre diferentes tipos de substratos micrométricos. Particularmente, foram investigados o comportamento dos compósitos micro-nanoestruturados desenvolvidos, frente à redução de metais e ao reforço mecânico de um polímero termoplástico (PVC). Para conduzir o presente estudo, dois tipos de NTC foram crescidos sobre substratos de carvão ativado, grafita e dióxido de titânio, pelo método da deposição química de vapor (CVD). Estes substratos são, tradicionalmente, usados como agentes de redução, adsorventes e cargas para reforço mecânico. As principais técnicas de investigação do presente trabalho foram a microscopia eletrônica de varredura (MEV), espectroscopia por energia dispersiva de raios-X (EDS), acoplada ao MEV, difração de raios-X e também, no caso dos compósitos de PVC, ensaios de tração mecânica em um texturômetro. Os resultados demonstram que existem combinações entre o tipo de NTC e o suporte microestruturado, que podem resultar em propriedades que não são observadas nos constituintes dos compósitos estudados, quando estes estão na forma isolada. Portanto, o crescimento de nanoestruturas sobre os substratos pode gerar propriedades híbridas como: a redução e adsorção nos NTC, de certos íons metálicos de Ag e Cu, sem o uso de agente redutor ou aplicação de potencial externo. E também, pode dar origem a aditivos de reforço mecânico para PVC que podem levar a consideráveis aumentos no módulo de elasticidade e limite de resistência à tração, em relação ao PVC isoladamente (aumentos de 5.068,21 % e 4.110,74%, respectivamente) / Carbon nanotubes (CNT) have been the subject of several theoretical and experimental researches due to their superlative intrinsic physicochemical properties, especially in the field of composites. However, there are some problems concerned to the successful transmission of these superior properties to the materials of interest. Hybrid materials have properties that are different from those of their individual components, which results from the interactions and also the quantities of the components. This work aimed at investigating the hybrid properties that can arise when carbon nanostructures are vertically grown on different types of microstructured substrates. Particularly, the behavior of the micro-nanostructured composites has been investigated as a function of the chemical reduction of metal ions and the mechanical reinforcement of a thermoplastic polymer (PVC). In order to conduct this study, two types of CNT were grown on the surfaces of charcoal, graphite and titanium dioxide through the chemical vapor deposition (CVD) method. These substrates are traditionally used as reducing agents, adsorbents and reinforcing fillers. The PVC composite samples were characterized, mainly, by mechanical traction tests in a texturometer, and the other samples were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS), and X-ray diffraction (XRD). The results demonstrated that there are combinations between specific types of CNT and microstructured supports that can lead to properties not observed in the isolated constituents of the composite. Therefore, the growth of nanostructures on substrates can generate hybrid properties, such as the reduction of Ag and Cu ions and their direct adsorption on CNT without the need of a reducing agent or application of an external potential, as in the case of some charcoals. Additionally, some of these composites can form mechanical fillers for PVC, which can lead to substantial increases in the elasticity modulus and tensile strength, (5.068,21% and 4.110,74%, respectively), when compared to the isolated PVC.
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HIGH PERFORMANCE BLENDS AND COMPOSITES: PART (I) CLAY AEROGEL/POLYMER COMPOSITES PART (II) MECHANISTIC INVESTIGATION OF COLOR GENERATION IN PET/MXD6 BARRIER BLENDSBandi, Suneel A. 12 July 2006 (has links)
No description available.
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plicação de polímeros na construção de nanomateriais híbridos auto-organizados / A polymer application in the construction of self-assembly hybrid nanomaterialsScaravelli, Roberta Cristina Barros 22 February 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In this work the single-step/single-phase synthesis of hybrid organic-inorganic core-shell gold nanoparticles (AuNPs), facilitated by amino-functionalized amphiphilic block copolymers that simultaneously play the roles of reductant and stabilizer, was investigated in this study. Experiments were devised with emphasis on the pH-responsive poly(ethylene oxide)-b-poly(2,3-dihydroxypropyl methacrylate)-b-poly[2-(diisopropylamino)ethyl methacrylate] triblock copolymer, which allows direct chemical cross-linking of the micellar structures to be performed. The polymer structure-reactivity relationship associated with the AuNP formation was established using a set of six structurally related macromolecules. AuNP formation was dependent on the aqueous dissociation equilibrium involving tertiary amino groups, the Au(III) speciation, and electrochemical redox potentials. The effects of these parameters on the synthesis of AuNPs change as the solution pH is increased from pH 3.5 (molecularly dissolved polymer chains; no AuNP formation) to 6.8 or higher (polymer chains self-assembled into spherical micelles; stable gold sols are produced), and Au(III) reduction potentials shift toward the cathodic region whilst the oxidation potential of deprotonated amino groups decreases.
Sigmoidal nanoparticle growth kinetics was observed in all cases after a characteristic induction period. Stable, well-defined, uniform polymer-coated gold colloids with localized surface plasmon resonance centered at 530 nm can be conveniently produced in one-pot, two-reactant, no work-up reactions when the stoichiometry is [N]/[Au] = 3.5 - 25.0. / Neste trabalho a síntese em única fase/etapa de nanopartículas de ouro híbridas orgânico-inorgânicas do tipo casca núcleo (AuNPs) facilitadas por copolímeros em bloco anfifílicos funcionalizados com grupos aminos e que simultaneamente atuam como agente redutor e estabilizante foi investigada. Os experimentos foram realizados com ênfase nas respostas frente ao pH do copolímero tribloco poli(óxido de etileno)-b-poli(metacrilato de 2,3-diidroxipropila)-b-poli(metacrilato de 2-(diisopropilamino)etila) e que permite a química direta de reticulação das estruturas micelares.
A relação entre estrutura e reatividade do copolímero associada à formação das AuNPs foi estabelecida usando uma série de seis macromoléculas semelhantes aos blocos constituintes do copolímero. A formação das AuNPs é dependente do equilíbrio de dissociação envolvendo grupos aminos terciários, espécies de Au(III) e também do potencial eletroquímico redox. Os efeitos desses parâmetros levam a formação de AuNPs quando da mudança de pH de 3,5 (cadeias poliméricas dissolvidas não formam AuNPs) para pH 6,8 ou maior (polímero auto-organizado em micelas esféricas coloides estáveis de ouro são produzidos), e quando o potencial de redução dos íons Au(III) mudam para a região catódica e o potencial de oxidação dos grupos aminos desprotonados presentes no copolímero diminui.
A cinética de crescimentos das AuNPs apresentou em todos os casos perfil sigmoidal após o período de indução característicos da síntese. Coloides de ouro estáveis, bem definidos e estabilizados pelo copolímero com ressonância plasmônica de superfície centrado em cerca de 530 nm foram produzidos em etapa única, dois reagentes, sem reações paralelas na estequiometria [N]/[Au(III)] entre 3,5 e 25.
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Sulfhydryl Reducing Agents Distinguish Two Subtypes of Angiotensin II Receptors in the Rat BrainSpeth, Robert C., Rowe, Brian P., Grove, Kevin L., Carter, Michelle R., Saylor, David 10 May 1991 (has links)
Two angiotensin II receptor subtypes were distinguished in the rat brain using in vitro receptor autoradiography based on the differential effects of sulfhydryl reducing agents on 125I-sarcosine1, isoleucine8 angiotensin II binding in various brain nuclei. At several nuclei, e.g. the hypothalamus, circumventricular organs and the dorsal medulla, 125I-sarcosine1, isoleucine8 angiotensin II binding was strongly inhibited by 30 mM β-mercaptoethanol or 5 mM dithiothreitol, whereas at other nuclei, e.g. the lateral septum, colliculi, locus coeruleus and medial amygdala, sulfhydryl reducing agents had either little effect on radioligand binding or enhanced the binding. The distribution of the sulfhydryl reducing agent inactivated subtype corresponds exactly with the distribution of DuP 753 sensitive (designated as AIIα) 125I-sarcosine1, isoleucine8 angiotensin II binding sites25. The subtype not inhibited by sulfhydryl reducing agents corresponds with the DuP 753 insensitive (designated as AIIβ) sites in the brain25. The sulfhydryl reducing agent effect on brain angiotensin II receptor subtypes is similar to that seen in angiotensin II receptor subtypes in peripheral tissues. These observations indicate that many previous studies of brain angiotensin II receptor binding that included 5 mM dithiothreitol in the assay medium overlooked the sulfhydryl reducing agent inactivated (AIIα) receptor subtype.
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[pt] SIMULAÇÃO TERMODINÂMICA E MODELAGEM CINÉTICA DA DECOMPOSIÇÃO TÉRMICA DO MGSO4.7H2O / [en] THERMODYNAMICS SIMULATIONS AND KINETICS MODELING OF MGSO4.7H2O THERMAL DECOMPOSITIONBRUNO MUNIZ E SOUZA 18 September 2023 (has links)
[pt] O sulfato de magnésio está presente em diversos rejeitos industriais
e de mineração. Ele e seus derivados poderiam ser reaproveitados em
várias áreas industriais, deixando de ser um rejeito para se tornar parte de
um processo. Seu óxido, MgO, pode ser utilizado em algumas funções,
como regulador de pH, dependendo de sua reatividade. Devido a isto sua
formação deve ocorrer em temperaturas abaixo das temperaturas de
decomposição do MgSO4. Assim sendo este trabalho avaliou aspectos da
decomposição do MgSO4 através de dois artigos. O artigo 1
(Thermodynamics Simulations and Kinetics Modeling of the Thermal
Decomposition of MgSO4.7H2O: Part 1 – Reducing Agent Effect), avaliou o
efeito cinético da utilização do carbono, através de quatro diferentes
agentes redutores, na decomposição térmica do MgSO4.7H2O, enquanto
que o artigo 2 (Thermodynamics Simulations and Kinetics Modeling of the
Thermal Decomposition of MgSO4.7H2O: Part 2 – Hydration Effect) analisou
as influências da taxa de aquecimento dos ensaios e do grau de hidratação
do sulfato de magnésio utilizado. Os ensaios termogravimétricos realizados
ao longo destes artigos, utilizaram amostras com massa de
aproximadamente 10 mg de mistura (sulfato + agente redutor) e estas
misturas tiveram uma relação estequiométrica de 1:1. Os experimentos
realizados no artigo 1, utilizaram como agentes redutores agentes
redutores, carvão vegetal, coque verde, coque breeze e grafite. No artigo
2, os sulfatos analisados foram o anidro, o monohidratado e o
heptahidratado e as taxas de aquecimento utilizadas foram de 5 K.min(-1)
, 10
K.min(-1)
, 15 K.min(-1) e 20 K.min(-1)
. Todos os dados obtidos dos ensaios
termogravimétricos foram processados através de modelagem matemática
para se obter os dados cinéticos. No artigo 1 a utilização dos agentes
redutores se mostrou eficiente reduzindo a energia de ativação da
decomposição do sulfato de magnésio de 22,731 kJ.mol(-1)
(sulfato puro)
para 340,391 kJ.mol(-1)
(coque verde), 196,120 kJ.mol(-1)
(grafite), 191,100
kJ.mol(-1)
(coque breeze) e 162,302 kJ.mol(-1)
(carvão vegetal). No artigo 2, a
taxa de aquecimento não se mostrou como um fator determinante para a
decomposição do MgSO4, já em relação a hidratação do sulfato de
magnésio, os resultados indicaram que uma pequena parcela de H2O no
sistema pode influenciar positivamente a decomposição, visto que os
valores de Ea médio foram de 404,5 KJ.mol(-1)
(mono), 407 KJ.mol(-1)
(anidro)
e 433,3 KJ.mol(-1)
(hepta). / [en] Magnesium sulfate is present in several industrial and mining wastes.
It and its derivatives could be reused in various industrial areas, ceasing to
be a waste to become part of a process. Its oxide, MgO, can be used in
some functions, as a pH regulator, depending on its reactivity. Due to this,
its formation must occur at temperatures below the decomposition
temperatures of MgSO4. Therefore, this work evaluated aspects of the
decomposition of MgSO4 through two articles. Article 1 (Thermodynamics
Simulations and Kinetics Modeling of the Thermal Decomposition of
MgSO4.7H2O: Part 1 – Reducing Agent Effect), evaluated the kinetic effect
of using carbon, through four different reducing agents, on the thermal
decomposition of MgSO4.7H2O, while article 2 (Thermodynamics
Simulations and Kinetics Modeling of the Thermal Decomposition of
MgSO4.7H2O: Part 2 – Hydration Effect) analyzed the influences of the
heating rate of the tests and the degree of hydration of the magnesium
sulfate used. The thermogravimetric tests carried out throughout these
articles used samples with a mass of approximately 10 mg of the mixture
(sulfate + reducing agent) and these mixtures had a stoichiometric ratio of
1:1. The experiments carried out in article 1 used reducing agents, charcoal,
green coke, breeze coke, and graphite as reducing agents. In article 2, the
sulfates analyzed were anhydrous, monohydrate, and heptahydrate and the
heating rates used were 5 K.min(-1)
, 10 K.min(-1)
, 15 K.min(-1)
, and 20 K.min(-1).
All data obtained from thermogravimetric tests were processed through
mathematical modeling to obtain kinetic data. In article 1, the use of
reducing agents proved efficient, reducing the activation energy of
magnesium sulfate decomposition from 22.731 kJ.mol(-1)
(pure sulfate) to
340.391 kJ.mol(-1)
(green coke), 196.120 kJ.mol(-1)
(graphite), 191,100 kJ.mol(-1)
(coke breeze) and 162,302 kJ.mol(-1)
(charcoal). In article 2, the heating rate
was not shown to be a determining factor for the decomposition of MgSO4,
in relation to the hydration of magnesium sulfate, the results indicated that
a small portion of H2O in the system can positively influence the
decomposition since the average Ea values were 404.5 KJ.mol(-1)
(mono),
407 KJ.mol(-1)
(anhydrous) and 433.3 KJ.mol(-1)
(hepta).
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[pt] DECOMPOSIÇÃO TÉRMICA DO SULFATO DE ZINCO NA PRESENÇA DE AGENTES MODIFICADORES DO MECANISMO REACIONAL / [en] ZINC SULFATE THERMAL DECOMPOSITION IN THE PRESENCE OF REACTION MECHANISM MODIFIERS AGENTSGABRIELA VICTORIA TOMASI KURBAN 14 September 2020 (has links)
[pt] O hidrogênio apresenta-se como um potencial combustível alternativo em substituição aos combustíveis fósseis e, por essa razão, estudos e pesquisas sobre as rotas de produção e armazenamento desse recurso estão em voga no meio científico. Os métodos para obtenção de H2 são diversos, no entanto, nem todos os métodos são provenientes de fontes renováveis. Os ciclos termoquímicos de quebra da molécula da água são alternativas promissoras para a geração de H2. Neste contexto, o ciclo do enxofre-iodo é um dos ciclos em destaque, caracterizando-se por um processo em três etapas cuja terceira etapa é a etapa desafiadora do ciclo, onde ocorre a decomposição do ácido sulfúrico que exige um gasto energético elevado. A utilização de sulfatos metálicos associados a agentes redutores e aditivos em substituição ao ácido sulfúrico no ciclo enxofre-iodo tem sido estudada. Deste modo, o presente trabalho de pesquisa avaliou a decomposição térmica do sulfato de zinco monohidratado na presença dos agentes modificadores enxofre elementar, Pd-(gama)Al2O3, CeO2 e CeO2/ZnO que estimulam a transformação do trióxido de enxofre no respectivo dióxido. Além de um estudo termodinâmico do sistema reacional e análises térmicas via TG que indicaram uma mudança no comportamento da decomposição do sulfato na presença do agente redutor e dos aditivos, o trabalho previu a caracterização dos produtos reacionais indicando a presença do óxido de zinco e um estudo cinético dos sistemas na presença dos agentes mencionados, permitindo o cálculo das energias de ativação e dos parâmetros cinéticos. A apreciação termodinâmica indicou um aspecto favorável quanto a diminuição da temperatura de decomposição do sulfato de zinco assim como no que diz respeito à transformação de SO3 em SO2. Na presença de Pd-(gama)Al2O3 a temperatura final da decomposição do sulfato ocorreu 100 graus Celsius abaixo da temperatura habitual. A perda de massa total calculada para a decomposição do sulfato puro foi de 55 por cento. Nos estudos com a presença dos agentes as perdas de massa total calculadas foram 60 por cento, 54 por cento, 62 por cento, 57 por cento correspondentes ao sulfato de zinco na presença do enxofre elementar, Pd-(gama)Al2O3, CeO2 e CeO2/ZnO, respectivamente. / [en] Hydrogen presents itself as a potential alternative fuel to replace fossil fuels and, for this reason, studies and research on the production and storage routes of this resource are in vogue in the scientific community. The methods for obtaining H2 are diverse, however, not all methods are from renewable sources. The thermochemical cycles of splitting water are promising alternatives. In this context, the sulfur-iodine cycle is one of the highlighted cycles, characterized by a three-stage process whose third stage is the challenging stage of the cycle, where the decomposition of sulfuric acid occurs, which requires a high energy expenditure for formation selection of sulfur dioxide and oxygen. The use of metal sulfates associated with reducing agents and additives in substitution for sulfuric acid in the sulfur-iodine cycle has been studied. Thus, the present research work evaluated the thermal decomposition of zinc sulfate monohydrate in the presence of elemental sulfur modifying agents, Pd-
(gamma)Al2O3, CeO2 and CeO2 / ZnO that stimulate the transformation of sulfur trioxide in the respective dioxide. In addition to a thermodynamic study of the reaction system and thermal analyzes via TGA that indicated a change in the sulphate decomposition behavior in the presence of the reducing agent and additives, the work predicted the characterization of the reaction products indicating the presence of zinc oxide and a study kinetics of the systems in the presence of the mentioned agents, allowing the calculation of activation energies and kinetic parameters. The thermodynamic assessment indicated a favorable aspect regarding the decrease in the decomposition temperature of zinc sulfate as well as with regard to the transformation of SO3 into SO2. In the presence of Pd-(gamma)Al2O3, the final temperature of the sulphate decomposition occurred 100 C degrees below the usual temperature. The total mass loss calculated for the decomposition of pure sulfate was 55 percent. In studies with the presence of agents, the calculated total mass losses were 60 percent, 54 percent, 62 percent, 57 percent corresponding to zinc sulfate in the presence of elemental sulfur, Pd-(gamma)Al2O3, CeO2 and CeO2 / ZnO, respectively.
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Rapid Method of Processing Sperm for Nucleic Acid Extraction in Clinical Researchde Gannes, Matthew K 29 August 2014 (has links) (PDF)
Background: Sperm contain highly compact nuclei, inhibiting DNA extraction using traditional techniques. Current methods extracting sperm DNA involve lengthy lysis and no means of stabilizing DNA, hindering clinical research.
Objective: We sought to optimize an efficient method of extracting high quality human sperm DNA.
Methods: Sperm from three volunteers were isolated using PureCeption. We tested 1) proteinase K with DNA/RNA Shield, 2) DTT and TCEP as reducing agents, 3) QIAshredder homogenization, and 4) stability of sperm DNA fresh (baseline) or after 4 weeks of storage at 4OC in DNA/RNA Shield using modified Quick-gDNA MiniPrep. DNA was PCR amplified using ALU primers and digested with Hinf1 restriction enzymes. DNA methylation was measured by MassARRAY.
Results: DNA concentrations were similar with (30.1+0.28ng/μL, 33.4+0.21ng/μL) and without (28.9+0.00ng/μL, 30.9+0.85ng/μL) proteinase K. Sperm cells were lysed after 1 and 20 minutes with 25mM TCEP and 100mM DTT respectively. TCEP (50mM) produced greater DNA concentrations (17.2+0.50ng/μL, 21.3+0.71ng/μL) than 50mM DTT (12.6+0.28ng/μL, 12.3+0.35ng/μL). Adding QIAshredder to 50mM TCEP increased DNA concentrations (25.9+0.35ng/μL, 21.7+0.49ng/μL versus 18.6+0.99ng/μL, 12.3+0.35ng/μL). At baseline and 4 weeks: 1) DNA concentrations were similar (36.2+2.75 ng/μL, 32.2+1.38ng/μL, 44.3+3.93ng/μL versus 40.0+2.98ng/μL, 37.6+1.38ng/μL, 38.7+3.93ng/μL respectively) and 2) DNA was equally amplified by PCR and digested with restriction enzymes. DNA methylation was similar at baseline and 4 weeks for SNURF (1.43+1.02%, 1.55+0.95%), PEG10 (3.69+0.66%, 4.28+1.52%), and H19 (88.93+3.24%, 91.78+2.00%).
Conclusions: We stabilized and isolated high quality DNA from human sperm using 5 minute versus > 2 hour lysis in other methods. Our methods may facilitate efficient clinical research.
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