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1.
Cationic lipids nowadays constitute a promising alternative to recombinant viruses for gene transfer. We have recently explored the transfection potential of a new class of lipids based upon the use of aminoglycosides as cationic polar headgroups. The encouraging results obtained with a first cholesterol derivative of kanamycin A prompted us to investigate this family of vectors further, by modulating the constituent structural units of the cationic lipid. For this study, we have investigated the transfection properties of a series of new derivatives based on a kanamycin A scaffold. The results primarily confirm that aminoglycoside-based lipids are efficient vectors for gene transfection both in vitro and in vivo (mouse airways). Furthermore, a combination of transfection and physicochemical data revealed that some modifications of the constitutive subunits of kanamycin A-based vectors were associated with substantial changes in their transfection properties.  相似文献   

2.
In an effort to enhance the gene-transfer efficiencies of cationic lipids and to decrease their toxicities, a series of new phosphoramidate lipids with chemical similarity to cell membrane phospholipids was synthesised. These lipids contained various cationic headgroups, such as arginine methyl ester, lysine methyl ester, homoarginine methyl ester, ethylenediamine, diaminopropane, guanidinium and imidazolium. Their transfection abilities, either alone or with the co-lipid DOPE, were evaluated in HEK293-T7 cells. We found that imidazolium lipophosphoramidate 7 a/DOPE lipoplexes gave the most efficient transfection with low toxicity (15 %). The luciferase activity was 100 times higher than that obtained with DOTAP/DOPE lipoplexes. The size, zeta potential, pDNA-liposome interactions and cellular uptakes of the lipoplexes were determined. No definitive correlation between the zeta potential values and the transfection efficiencies could be established, but the uptake of lipoplexes by the cells was correlated with their final transfection efficiencies. Our results show that imidazolium phosphoramidate lipids constitute a potential new class of cationic lipids for gene transfer.  相似文献   

3.
高通量筛选与组合合成技术相结合是发现创新药物的重要技术手段之一。这极大地提高了化合物库的建立速度及对目标分子、活性物质以及先导药物的筛选速度,在农药创制过程中可以缩短新农药分子的研发周期,提高成功率。  相似文献   

4.
5.
New pyrimidinium cationic surfactants containing a positively charged nitrogen atom of the pyrimidine ring and a long-chain alkyl group of 6,8,10,12,14 carbon atoms were prepared. The structural assignment of these compounds was made on the basis of the elemental analysis and spectroscopic data, infrared, nuclear magnetic resonance and mass spectroscopy. Surface tension and after-treatment of direct dyed cotton fabrics were determined for these surfactants. Antibacterial activities also were examined.  相似文献   

6.
李善茂  刘国宏 《化学试剂》1999,21(6):356-359,378
利用α-酮酸和4,5-二胺基邻苯二酰肼合成了3种新发光试剂(EDIQ、HDIQ和CEDIQ)。详细地研究了过氧化氢浓度、铁氰化钾浓度和氢氧化钠浓度对化学发光强度的影响,并对其化学发光性能进行了研究,结果发现新发光试剂EDIQ、HDIQ和CEDIQ发光强度分别为鲁米诺的0.83、3.51和1.92倍。  相似文献   

7.
Polypropylene fabrics were modified with 2N‐morpholino ethyl methacrylate by electron beams and grafting. Then, the modified fabrics were quaternized with different alkylating agents, such as benzyl chloride, monochloroacetic acid, chlorosulfonic acid, and chloroethanol. The reaction completion was calculated from the increase in the fabric weight. The modified polypropylene fabrics were characterized by microanalysis and IR spectroscopy. The moisture regain was measured at 20°C and 65% relative humidity. The modified fabrics were sufficiently hydrophilic to adsorb the metal ion Cu2+ from a CuSO4 solution. Their antimicrobial properties were evaluated. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2917–2922, 2003  相似文献   

8.
以ECH(环氧氯丙烷)、TMA(三甲胺)和HCl(盐酸)为主要原料,采用水相法分两步合成了阳离子醚化剂CHPTMAC(3-氯-2-羟丙基三甲基氯化铵)。以CHPTMAC改性织物对染料废水的吸附率、ECH转化率作为考核指标,采用单因素试验法优选出合成CHPTMAC的最佳工艺条件。研究结果表明:当反应时间为5 h、反应温度为30℃、n(ECH)∶n[TMAHC(三甲胺盐酸盐)]=1.0∶1和反应液p H为8时,CHPTMAC产率较高、副反应产物少,并且ECH转化率(为94.37%)和改性织物吸附率(98%)均相对较高。  相似文献   

9.
阳离子型聚氨酯乳液的合成与性能初探   总被引:1,自引:1,他引:1  
对阳离子水性聚氨酯乳液及其膜性能进行了初步的研究。用N -2 10 ,甲苯二异氰酸酯 (TDI) ,N -甲基二乙醇胺(MDEA)为原料 ,以及丙酮作为溶剂来制备阳离子型水分散聚氨酯。讨论了MDEA的用量和NCO/OH比值对乳液及其膜性能的影响。并进行了红外光谱分析。  相似文献   

10.
A novel method for combinatorial synthesis and screening of uniform‐size molecularly imprinted microspheres using a microfluidic device is presented, in which a new microfluidic device containing twelve pairs of “” shape microchannels is designed to produce droplets and imprinted microspheres via controlled suspension polymerization. This technique combines molecular imprinting and microfluidic device with the combinatorial chemical approach, allowing rapid screening and optimization of uniform imprinted microspheres. On the example of chloramphenicol (CAP), the imprinted microspheres of CAP were prepared by a combinatorial approach using water with 1.5% polyvinyl alcohol as continuous phase, and ethyl acetate–chloroform (4:1, v/v) as porogenic solvents. Functional monomers methacrylic acid (MAA), 4‐vinylpyridine or acrylamide were screened, and the molar ratio of template molecule to functional monomer was optimized. The results indicate that MAA is the best functional monomer for imprinting of CAP, and when the molar ratio of CAP to MAA is 1:5, the imprinted microspheres exhibit the best imprinting performance, and have good monodispersity and selectivity. This combinatorial protocol is well suited for fast and efficient screening and optimization of synthesis for uniform imprinted microspheres because 12 kinds of imprinting conditions can be performed simultaneously in this microfluidic device. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers  相似文献   

11.
We present a new high-throughput screening method for the selection of powerful water-soluble antiradiation compounds. This method, which uses conventional immunoassay techniques, allowed the capacity of a given compound to protect thymidine from irradiation to be evaluated. By applying this assay to an antioxidant library, we showed for the first time that norbadione A, a well-known mushroom pigment, has pronounced atypical antiradiation properties.  相似文献   

12.
刘海彬  李双奇  王文忠 《化学试剂》2011,33(2):124-126,144
通过9-芴甲醛与相应的芳胺衍生物反应合成了两种新型含芴Schiff碱化合物:9-亚甲基19-亚(2-氨基芴)基芴和9-亚甲基-9-亚(2-甲基苯胺)基芴,其结构经核磁共振谱、红外光谱和质谱表征.吸收光谱法测定了两种含芴Schiff碱衍生物在乙醇、四氢呋喃、环己烷和氯仿中的最大吸收波长(λmax),并探讨了分子结构和溶剂...  相似文献   

13.
A new type of cationic surfactant, 6-O-monoesters of 3-(trimethylammonio)propyl d-glucopyranoside, was prepared in high yield by a simple chemoenzymatic synthesis. Surface-active properties of the compounds were found to be highly dependent on the fatty acyl chain length in the 6-O-position with the dodecanoyl and tetradecanoyl esters exhibiting the highest ability to lower surface tension as well as having the lowest critical micelle concentration values. Furthermore, the dodecanoyl ester had excellent foaming properties. The new surfactants also showed antimicrobial activity. Thus, the most potent compound, the dodecanoyl ester, was able to inhibit growth of both bacterial (Gram-positive as well as Gram-negative) and fungal test strains. The antimicrobial effect was somewhat weaker compared to benzalkonium chloride, one of the most frequently used cationics for topical disinfection. However, compared to benzalkonium chloride, the new cationics exhibit a highly improved compatibility with anionic surfactants, as no precipitation took place even in highly concentrated solutions thereby providing a much more robust antimicrobial system. Finally, the new surfactants are expected to be readily biodegradable because they are carbohydrate ester-based.  相似文献   

14.
High-throughput screening (HTS) is one of the newest techniques used in drug design and may be applied in biological and chemical sciences. This method, due to utilization of robots, detectors and software that regulate the whole process, enables a series of analyses of chemical compounds to be conducted in a short time and the affinity of biological structures which is often related to toxicity to be defined. Since 2008 we have implemented the automation of this technique and as a consequence, the possibility to examine 100,000 compounds per day. The HTS method is more frequently utilized in conjunction with analytical techniques such as NMR or coupled methods e.g., LC-MS/MS. Series of studies enable the establishment of the rate of affinity for targets or the level of toxicity. Moreover, researches are conducted concerning conjugation of nanoparticles with drugs and the determination of the toxicity of such structures. For these purposes there are frequently used cell lines. Due to the miniaturization of all systems, it is possible to examine the compound's toxicity having only 1-3 mg of this compound. Determination of cytotoxicity in this way leads to a significant decrease in the expenditure and to a reduction in the length of the study.  相似文献   

15.
16.
Hydroxy fatty acid (HFA) esters of long-chain alcohols, such as hydroxy stearates, have potential applications from lubricants to cosmetics. These esters were synthesized enzymatically to overcome the problems associated with chemical processes. An immobilized lipase, Rhizomucor miehei, was employed as catalyst in the esterification reaction between hydroxy-stearic acid as a source of HFA and monohydric fatty alcohols (C8–C18). The yields of esters were in the range of 82–90% by conducting the reactions at 65±2°C, 2–5 mm Hg pressure, and 10% lipase concentration. The products were analyzed by infrared spectroscopy, and some of their analytical characteristics were determined.  相似文献   

17.
In the present work we have applied combinatorial methodology to the hydrothermal synthesis and characterisation of perovskites. In a first series with 48 samples in the (Pb,Ba,Sr)ZrO3 compositional field, synthesis conditions were optimised by variation of pH. In a second series of 96 samples the (Pb,Ba)(Zr,Ti)O3 compositional field was investigated, with the aim to control crystallinity and particle size. Using powder X-ray diffraction (XRD), it was established that most compositions crystallised readily within 3–23 h at 200 °C in 2.0–3.3 M KOH. Using scanning electron microscopy (SEM), particle size was determined to be from 3 to 8 μm for the pure zirconates to 0.2–1 μm for the pure titanates. Microprobe wavelength dispersive spectroscopy (WDS) was used for chemical analysis. It was found that particle size was determined primarily by bulk chemistry whereas a polyacrylamide additive and pH had little effect. It has been shown that combinatorial hydrothermal synthesis and characterisation techniques are fully applicable to the synthesis and basic characterisation of perovskites.  相似文献   

18.
Three cationic surfactants were prepared. A condensation reaction between dimethylaminopropylamine (DMAPA) and benzaldehyde was performed. The produced Schiff base was quaternization with three fatty alkyl bromide with different carbon chain length separately to form the desired cationic surfactants. The chemical structure of synthesized cationic surfactants was confirmed by FTIR, 1H NMR and mass spectroscopy. It was found that the chemical structure of prepared compounds has an effect on surface properties, where increasing the hydrophobic chain length decrease the values of CMC, Гmax while Amin value was increased. The thermodynamic parameters showed that adsorption and micellization processes are spontaneous. It is clear that the prepared cationic surfactants at first tend to adsorb at surface, then it aggregate to form micelle. The prepared surfactants showed good biological activity against gram positive and negative bacteria and fungi in the following order of II (C12) > I (C10) > III (C16). The serial dilution method was used to evaluate the inhibiting effect of these compounds on the sulfate reducing bacteria growth.  相似文献   

19.
Drug discovery today includes considerable focus of laboratory automation and other resources on both combinatorial chemistry and high-throughput screening, and computational chemistry has been a part of pharmaceutical research for many years. The real benefit of these technologies is beyond the exploitation of each individually. Only recently have significant efforts focused on effectively integrating these and other discovery disciplines to realize their larger potential. This technical note will describe one example of these integration efforts.  相似文献   

20.
Eight lipases were screened for their ability to synthesize estolides from a mixture that contained lesquerolic (14-hydroxy-11-eicosenoic) acid and octadecenoic acid. With the exception ofAspergillus niger lipase, all 1,3-specific enzymes (fromRhizopus arrhizus andRhizomucor miehei lipases) were unable to synthesize estolides.Candida rugosa andGeotrichum lipases catalyzed estolide formation at >40% yield, with >80% of the estolide formed being monoestolide from one lesquerolic and one octadecenoic acyl group:Pseudomonas sp. lipase synthesized estolides at 62% yield, but the product mixture contained significant amounts of monoestolide with two lesquerolic acyl groups as well as diestolide. ImmobilizedR. miehei lipase was chosen to catalyze the esterification of mono-and polyestolide, derived synthetically from oleic acid, with fatty alcohols or α,ω-diols. Yields were >95% for fatty alcohol reactions and >60% for diol reactions. In addition, the estolide linkage remained intact through the course of the esterification process. Esterification of estolides improved the estolide’s properties—for example, lower viscosity and higher viscosity index—but slightly raised the melting point. Estolides and, particularly, estolide esters may be suitable as lubricants or lubricant additives.  相似文献   

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