CTAB toxicity

Concerning SDAs, however, the presence of CTAB in the shell is not desirable for in vivo applications because of its toxicity.251,252 In fact, the deliberate displacement of CTAB from the AuNR surface with a commercially available mPEG-SH has been demonstrated.242 However, in comparison to 2D gold surfaces, the assembling of thio-lated molecules on the surface of gold nanorods is slower and thus higher excesses of thiolates have to be employed for efficient CTAB removal. For example, 24 h have been used for mPEG-SH and 72 h have been used for thiolated DNA.253... 

ODNs directed to a point mutation in codon 12 of the HA-ras mRNA adsorbed to such nanoparticles were injected into tumor tissue, and suppressed oncogene-mediated tumor proliferation at concentrations 100 times lower than the free oligonucleotides [435], Because of the negative surface potential ( -potential) of polycyanoacrylate particles, a cationic copolymer such as DEAE-dextran (known as a transfection enhancer), or a hydrophobic cationic detergent such as CTAB, are usually used. In the meantime, base-modified nanoparticles of the methacrylate type have also been described [399-401, 404, 405, 407]. They have shown to increase plasma stability of ODNs and increase cellular uptake. Effects of toxicity were observed depending on the type of modification. As they are also used as car-... 

Ionic surfactants are more toxic for bacteria than nonionics [4]. Because of this fact, CTAB concentrations selected for the tests were lower than its critical micelle concentration (CMC) of 0.036% m/v. Corresponding solutions of each concentration were prepared and sterilized by vacuum filtration using a Millipore membrane of 0.45 um pore diameter. 

Interesting data on the application of microemulsions in analytical chemistry are given in [303]. In recent time, aprotic solvents, such as acetonitrile, have been widely used in titrimetric methods. However, these solvents are toxic, flammable and have a number of merely technical disadvantages such eis high dielectric constant which narrows the number of substances determined. The titration of week acids, such as o-chlorophenol, jo-nitrophenol, decanoic acid, with amines in the form of o/w emulsions containing CTAB and butanol is possible. This section deals only with some aspects of surfactant application in novel technologies, but these applications demonstrate a continuous further development. 

The addition of calcium and EDTA reduced the toxicity at least 10% of 2,6-dinitrocresol, 2,4-dinitrophenol, 2,6-dinitrophenol, 2,6-dinitrotoluene, 2-methyl resourcinol, 3-phenoxybenzoate, 2,4-dinitrocresol, the detergent CTAB, the antibiotic Neomycin, p-hydroxybenzoate, pentachlorophenol, salicylic acid, and trichloroethylene. 

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