Poly anion injection

Figure 14.6 Inhibitory effects of poly anions on the hepatic uptake of 32P-labeled plasmid/cationic liposome complexes administered intravenously into mice at 1 minute after DNA iv injection of excess poly anions. Hepatic accumulation was determined at 10 minute post-injection. Key (orange) free plasmid, (pale orange) 1 5 w/w plasmid/LipofectACE, (blue) 1 5 w/w plasmid/LipofectACE. Reproduced with permission from Physicochemical and pharmacokinetic characteristics of DNA/cationic liposome complexes, Mahato R.I. et al. (1995) J. Pharm. Sci., 84 1267-1271...

Simultaneous determination of both cations and anions in acid rain has been achieved using a portable conductimetric ion-exclusion cation-exchange chromatographic analyzer.14 This system utilized the poly(meth-ylmethacrylate)-based weak acid cation exchange resin TSK-Gel OA-PAK-A, (Tosoh , Tokyo, Japan) with an eluent of tartaric acid-methanol-water. All of the desired species, 3 anions and 5 cations, were separated in less than 30 minutes detection limits were on the order of 10 ppb. Simultaneous determination of nitrate, phosphate, and ammonium ions in wastewater has been reported utilizing isocratic IEC followed by sequential flow injection analysis.9 The ammonium cations were detected by colorimetry, while the anions were measured by conductivity. These determinations could be done with a single injection and the run time was under 9 minutes. 

A flow injection optical fibre biosensor for choline was also developed55. Choline oxidase (ChOX) was immobilized by physical entrapment in a photo-cross-linkable poly(vinyl alcohol) polymer (PVA-SbQ) after adsorption on weak anion-exchanger beads (DEAE-Sepharose). In this way, the sensing layer was directly created at the surface of the working glassy carbon electrode. The optimization of the reaction conditions and of the physicochemical parameters influencing the FIA biosensor response allows the measurement of choline concentration with a detection limit of 10 pmol. The DEAE-based system also exhibited a good operational stability since 160 repeated measurements of 3 nmol of choline could be performed with a variation coefficient of 4.5%. 

The extruder can be used for a variety of polymerizations even if no preformed polymer is present.89 These include the continuous anionic polymerization of caprolactam to produce nylon 6,90 anionic polymerization of capro-lactone 91 anionic polymerization of styrene 92 cationic copolymerization of 1,3-dioxolane and methylal 93 free radical polymerization of methyl methacrylate 94 addition of ammonia to maleic anhydride to form poly(succin-imide) 95 and preparation of an acrylated polyurethane from polycaprolactone, 4,4 -methylenebis(phenyl isocyanate), and 2-hydroxyethyl acrylate.96 The technique of reaction injection molding to prepare molded parts is slightly different. Polyurethanes can be made this way by... 

Wang et al. [6] have fabricated a dualinjection electrophoretic poly(methyl methacrylate) (PMMA) microchip. It consists of two crosses on both sides of the chip and one separation channel. Anions and cations can be injected... 

From the response of the injecting charge normalised to the saturated value based on Equation 8.1, the diffusion coefficient of dopant ions can be estimated. The diffusion constants in polyaniline [13] and poly(o-methoxyaniline) film [23] in various electrolytes at pH = 0 have been summarised. The diffusion constants of poly (o-methoxyaniline) are always larger than that of polyaniline, as the oxidation occurs by ejection of protons in poly (o-methoxyaniline), while in the case of polyaniline the oxidation occurs by injection of bulky anions as discussed previously. 

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