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1.
This paper presents the manufacturing of biochips by using the COOH- derived polymer coating deposited by plasma polymerization of acrylic acid. This technology is based on depositing a thin layer obtained by plasma polymerization of acrylic acid which allows a further covalent immobilization of biomolecules on glass substrates. The plasma power value was optimized to maximize the stability of plasma polymerized acrylic acid (PPAA) coatings in water, which has a very important role for such applications. In order to obtain a covalent immobilization of DNA probes on the PPAA coated surface, the activation protocol of carboxylic function was carried out with the help of N-Hydroxy Succinimide and 1-Ethyl-3-(3-DimethylAminopropyl) Carbodiimide. The efficiency of PPAA coated in microarray applications was compared with two types of commercial slides. Such surfaces have shown very interesting results in terms of relative density of attached DNA probe molecules and signal-to-background ratio measured for target DNA hybridization. Nonspecific DNA bonding measurements showed only a small amount of nonspecific physisorption between the DNA probe and the PPAA-activated surfaces. This work shows that the plasma polymerization technique can be successfully applied to produce a high-quality glass surface for the manufacturing of DNA arrays.  相似文献   

2.
Plasma copolymerization was carried out from the monomer mixtures of acrylic acid with hexamethylxdisilozane and hexametydisillazane, and the membranes composed of the Si-C and/or Si-O networks sustaining carboxylic acid group were fabricated. The carboxylic acid contents were dependent on the discharge power conditions as well as the monomer ratio, and carboxylic acid was introduced at the more density in the polymerization by plasmas under the moderate power conditions. The plasma polymer coatings were effective for the adsorption of lysozyme especially on the plasma copolymer films of acrylic acid.  相似文献   

3.
An organic micro-fluidic device (O-MFD) on silicon/glass substrate was fabricated using plasma polymerisation of acrylic acid (ppAc) with optical lithography including wet and dry etching techniques. The surface chemistry of O-MFD was controlled by depositing ppAc films on MFD. The results showed that these surfaces have more than 50% retention of original monomer functionalities (-COOX) with significant concentration of CO and C-OX at the surface. The water fluid velocity in 100 μm wide and 100 μm deep micro-channels of ppAc deposited O-MFD was increased by a factor of 10 relatively uncoated surfaces. The mixing of 10% of blood in the water has showed a decrease of about 100 μm/s in the fluid velocity relative to water and 10% red colour dye mixed water. The decrease in the fluid velocity of blood mixed water showed the possibility of blood cells interaction with the highly functional ppAc surfaces of micro-channel in O-MFD and that could have advantages in biological fluids (such as protein) separation.  相似文献   

4.
The graft copolymerization of acrylic acid (AA) onto commercial acrylic fibers (PAN) has been studied using Azobis(isobutyro)nitrile (AIBN) as an initiator. AA grafting initiated by radicals formed from thermal decomposition of AIBN. In this study, the effects of monomer and initiator concentration, time and temperature reaction on the grafting yield have been investigated. The optimum conditions for this grafting reaction were obtained with an AA concentration of 1.67 M, an AIBN concentration of 0.0097 M, a reaction temperature of T=85 °C and with reaction time of 60 minutes. The fiber structure has been investigated by different experimental techniques of characterization such as Fourier transform infrared spectroscopy (FT‐IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), water absorption and also in this study has been investigated the mechanical property. The thermal analysis data showed that increasing in grafting yield, decreases the thermal stability of fiber. Grafting also affected slightly the fiber morphology. The experimental data of mechanical properties show clearly that by increasing of grafting yield, max extension will decrease. Grafting of poly AA improved water absorption.  相似文献   

5.
利用乳液聚合的方法制备水性胃溶型药物包衣用丙烯酸树脂,此法制备的水性药物包衣材料性能稳定,无污染,成本低,包衣效率高.分别考察了相比、乳化剂及其用量、引发剂及其用量、搅拌速度、加料方式、反应温度等对实验结果的影响.  相似文献   

6.
In this work, a weakly acidic ion exchange fiber (PTFE-g-AA) has been prepared by 60Co irradiation grafting with acrylic acid (AA) onto the polytetrafluoroethylene (PTFE) fiber. The grafted fiber was characterized by FTIR, SEM and TGA technique. The exchange capacity of the PTFE-g-AA fiber is 3.87 mmol/g. The adsorbent material was employed for Er(III) uptaking by batch and column experiments. Kinetics studies showed that the adsorption process obeyed pseudo-second-order kinetics. The adsorption isotherms followed both the Freundlich model and Langmuir model. The maximum adsorption capacity of the PTFE-g-AA fiber for Er(III) was evaluated to be 142.0 mg/g for the Langmuir model. It was found that 0.75 M HCl–0.25 M NaCl solution provided effectiveness of the desorption of Er(III) from the PTFE-g-AA fiber. Various thermodynamic parameters such as standard enthalpy (ΔH0), standard entropy (ΔS0) and standard free energy (ΔG0) were evaluated. The adsorption of Er(III) on the PTFE-g-AA fiber was found to be endothermic in nature. The Thomas model was successfully applied to experimental data to predict the breakthrough curves and to determine the characteristics parameters of the column useful for process design.  相似文献   

7.
聚丙烯酸钠高吸水性树脂的性能改善   总被引:3,自引:0,他引:3  
采用水溶液聚合的方法合成了聚丙烯酸钠阴离子型高吸水性树脂 ,并通过改变聚合过程中的添加剂和对吸水性聚合物进行表面交联反应处理 ,对产品性能进行了研究。结果表明 :在聚合过程中添加适当的添加剂和对产品进行表面交联反应处理 ,能显著地改善产品性能  相似文献   

8.
Chitosan and polyacrylic acid (PAA) both have weak, short-lasting bioadhesive properties; therefore, a hybrid particle composed of a chitosan derivative and PAA could be used as a new bioadhesive agent. Using simultaneous in-situ monitoring with a multidetection system, N-carboxymethyl chitosan was ionically bonded to acrylic acid and then polymerized using potassium persulphate as the initiator (N-CMCA-Dh of 165 nm). The PAA on N-CMCA was crosslinked using N,N-methylene-bisacrylamide (N-CMCAC-Dh of 141 nm). During polymerization, the solution developed a milky white appearance, and polymerization kinetics was determined to be 3.2 × 10−3 ± 4.0 × 10−6 mmol/min. The reaction for PAA alone was 1.7 times faster than that of the hybrid system. The particles showed an increase in thermal stability and reduction of thermal-mass loss compared with the N-CMC alone. The N-CMCAC particles showed the highest bioadhesion onto the stomach. The gastroprotection index of N-CMChAC particles against ethanol/HCl-induced ulcers in mice was 68.2 ± 6.4%. Similar results were observed for omeprazole (74.2 ± 5.3%). The particles obtained in this work have potential for use in drug delivery to the stomach, perhaps to aid in treating ulceration and inflammation, and can be used as a system for the prevention of ethanol-induced ulcers.  相似文献   

9.
原位聚合法制备壳聚糖-g-聚丙烯酸/高岭土复合树脂   总被引:1,自引:0,他引:1  
利用无机粘土矿物与烯类单体的接枝共聚反应制备复合高吸水性树脂,具有改善树脂吸水性能、增强凝胶强度、降低产品成本的优点。以高岭土、壳聚糖和丙烯酸为原料,在水溶液中通过接枝共聚反应合成了壳聚糖接枝共聚丙烯酸/高岭土复合吸水树脂。以丙烯酸量为基准,研究了交联剂、引发剂、壳聚糖、高岭土等与丙烯酸的不同质量比对复合树脂吸水倍率的影响。红外光谱分析结果表明,丙烯酸、壳聚糖和高岭土共同参与了接枝聚合反应。以过硫酸胺为引发剂,N,N-亚甲基双丙烯酰胺为交联剂,丙烯酸中和度为70%,引发剂用量0.3%,交联剂用量为0.05%,壳聚糖与丙烯酸的质量比为0.13,高岭土与丙烯酸质量比为0.13时,高吸水性树脂具有较好的综合吸液性能。  相似文献   

10.
建立胃粘液细胞原代培养的方法,并在此基础上观察幽门螺秆菌(Hp)对它的损伤作用。取水囊引产的胎龄5个月以上胚胎的胃粘膜,采用组织块贴壁培养的方法进行培养,用倒置显微、电镜进行形态学鉴定,并用电镜观察其与Hp共培养后形态学变化。结果细胞为多边形,呈簇状或片状生长,排列紧密,电镜下见细胞表面有微绒毛,胞浆内有丰富的粗面内质网、高尔基体及粘液分泌颗粒,细胞同有紧密连接。加入Hp后,原代培养的胃粘液细胞出现空泡变性,有部分细胞发生凋亡,其核固缩。胚胎的胃粘液细胞原代培养不失为一种体外研究Hp相关胃部疾病的较理想模型。  相似文献   

11.
含柔性间隔基丙烯酸液晶化合物的合成及介晶性研究   总被引:1,自引:0,他引:1  
以丙烯酸、溴乙醇、对羟基苯甲酸、4-羟基苯甲醛、4-甲氧基苯胺为原料,经醚化、酰氯化、酯化和希夫碱反应合成中间体和液晶化合物.通过红外光谱、核磁共振等对化合物的结构进行表征.最后利用偏光显微镜测试目标产物的液晶性能.结果表明:含柔性间隔基的化合物具有很好的向列相液晶性能,目标化合物的液晶相宽度达到110~C左右,具有广阔的应用前景.  相似文献   

12.
硝磷酸腐蚀的CdTe太阳电池性能   总被引:2,自引:0,他引:2  
CdTe薄膜的腐蚀是制作CdS/CdTe光伏电池的重要技术之一,本实验采用硝磷酸溶液(硝酸1%+磷酸70%+去离子水29%)腐蚀CdTe薄膜,通过XRD测试发现在CdTe膜上生成了碲层.随后,在腐蚀后的CdTe薄膜上分别沉积了几种结构的背接触层,并制备出相应结构的CdTe太阳能光伏电池.通过电池的光、暗I-V和C-V特性测试,以ZnTe/ZnTe:Cu/Ni为背接触的小面积太阳电池,其性能优于其它背接触的电池.实验结果表明器件性能与碲的生成和铜的扩散密切相关.  相似文献   

13.
先制备出粒径均匀、形态一致的乳胶粒 ,采用后处理过程得到大量带有微孔的颗粒 ,并对共聚物进行测试分析。同时论述了三元共聚物反应组分的影响  相似文献   

14.
淀粉与丙烯酸接枝共聚物吸水性能的影响因素研究   总被引:2,自引:0,他引:2  
采用溶液聚合的方法,制备了淀粉与丙烯酸接枝共聚物;用FTIR等方法对共聚产物结构进行了表征;研究了聚合反应温度、糊化时间、丙烯酸中和度、产物烘干温度、丙烯酸与淀粉不同混合比例等因素对接枝产物吸水性能的影响,优化出了在实验室用玉米淀粉和丙烯酸接枝共聚制备高倍率吸水树脂的工艺条件,制备的吸水树脂吸去离子水近1000g/g.  相似文献   

15.
Titanium oxide (TiOx) thin films were prepared on transparent conducting substrate (fluorine-doped tin oxide) by cathodic electrolysis of a solution containing a titanium bis(ammonium lactato)dihydroxide and an ammonium nitrate at 323 K. Post-deposition treatment: calcination at 723 K or hot-water treatment at > 363 K promoted the growth of an anatase type crystalline phase in the TiO2 thin film, as evidenced by X-ray diffraction and X-ray photoelectron spectroscopy. The calcined films were used as electrodes of a dye-sensitized solar cells and the cells' energy conversion efficiency was comparable to that obtained with commercially available TiO2 nanoparticle electrodes.  相似文献   

16.
17.
Direct formic acid fuel cells (DFAFCs) allow highly efficient low temperature conversion of chemical energy into electricity and are expected to play a vital role in our future sustainable society. However, the massive precious metal usage in current membrane electrode assembly (MEA) technology greatly inhibits their actual applications. Here we demonstrate a new type of anode constructed by confining highly active nanoengineered catalysts into an ultra-thin catalyst layer with thickness around 100 nm. Specifically, an atomic layer of platinum is first deposited onto nanoporous gold (NPG) leaf to achieve high utilization of Pt and easy accessibility of both reactants and electrons to active sites. These NPG-Pt core/shell nanostructures are further decorated by a sub-monolayer of Bi to create highly active reaction sites for formic acid electro-oxidation. Thus obtained layer-structured NPG-Pt-Bi thin films allow a dramatic decrease in Pt usage down to 3 ~tg.cm-2, while maintaining very high electrode activity and power performance at sufficiently low overall precious metal loading. Moreover, these electrode materials show superior durability during half-year test in actual DFAFCs, with remarkable resistance to common impurities in formic acid, which together imply their great potential in applications in actual devices.  相似文献   

18.
首先合成了含有8个羟基、结构极为对称的八聚[2-(2-羟基乙氧基)二甲基硅氧基]倍半硅氧烷,再以其为核引发D,L-丙交酯发生开环聚合,制备了含有八臂聚乳酸的星型有机-无机杂化POSS-PDLLA材料,通过FTIR、1H-NMR、GPC、DSC和TGA等手段对八羟基倍半硅氧烷和POSS-PDLLA杂化材料的化学结构和性能等进行了表征。结果表明,成功合成了单分散性的八羟基倍半硅氧烷,而POSS-PDLLA杂化聚合物分子量分布极窄(小于1.1)、玻璃化转变温度为43.6℃、热稳定性良好,具有与线性聚乳酸截然不同的特性。  相似文献   

19.
对稀土固体超强酸SO_4~(2-)/TiO_2-Ce~(4 )催化剂直接法催化合成聚乳酸反应机理进行了研究,实验结果表明:SO_4~(2-)/TiO_2-Ce~(4 )直接法催化剂合成聚乳酸的聚合机理是酸性聚合,酸性越强所合成聚乳酸的分子量越高。  相似文献   

20.
采用硝磷酸(NP)背表面刻蚀工艺并结合真空共蒸发法分别沉积了几种背接触层材料,研究了NP腐蚀对CdTe薄膜性能及背接触层的影响.结果表明:NP腐蚀后在CdTe薄膜上产生了富碲层;退火后,碲容易与背接触材料中的铜反应生成CuxTe.通过严格控制和优化腐蚀工艺,选择ZnTe/ZnTe:Cu作为背接触层材料,可制备出优异性能的CdTe太阳电池.  相似文献   

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