Eluents sodium perchlorate

This problem was resolved by Nakae et al. [7] using non-polar octadecylsilica as the stationary phase and a solution of 0.1 M of sodium perchlorate in methanol/water (80 20) as the mobile phase. The ternary system (water-alcohol-salt), previously used by Fudano and Konishi [8] as an eluent for the separation of ionic surfactants at higher concentrations, induced the so-called salting out effect . The addition of the organic solvent to the water modified the polarity of the eluent and produced a good separation within a short period of time [9]. It also has the function of dissociating the surfactant micelles in individual molecules that are dissolved in the eluent [8], The presence of the salt (NaC104) in the mobile phase has a considerable influence on... 

Figure 3.4. Eluent pH vs. anion capacity factor, k. Conditions 100 x 4.6 mm (multicharge, weak base, anion exchanger) column, 15 mM sodium perchlorate eluent, UV detection at 200 nm (from Ret [10], with permission).

The data in Table 5.4 (perchloric acid eluent) and Table 5.5 (sodium perchlorate eluent) were plotted according to Eq. 5.19. Linear plots were obtained in all ca.ses. (See Fig. 1 for an example.) The slopes, obtained by linear regression, arc given in Table 5.4 for perchloric acid and in Table 5.5 for sodium perchlorate. In most cases, the negative slope was very close to the charge on the metal ion. The somewhat low values obtained for Be(II) and Bi(III) in Table 5.6 may be due to partial hydrolysis of... 

Selectivity of Sulfonated Cation-Exchange Resin for Metal Cations Table 5.5. Retention factors (k) of various cations when sodium perchlorate eluents are used. 

A silver wire electrode coated with AgCl has excellent selectivity. An ion chromatogram obtained with 4.5 mM sodium perchlorate as the eluent gave sharp peaks for 1 mM chloride, bromide, iodide, thiocyanate and thiosulfate but no response to equi-... 

Figure 6.20. Gradient elution with potentiometric detection. Eluent 3.5-10.0 mM sodium perchlorate flow-rate, l.6mL/min injection volume, 20 pL analyte concentration, 1.0 mM. (From Ref. [2.3J witli permission).

Figure 2 Separation of peptides via hydrophilic interaction chromatography on two different packings. IChromatographic conditions Sample substance P fragments. Off-umns (I) PolyHydroxyethyl A (II) PolySulfoethyl A, 200 mm x 4.6 mm. Flow rate 0.8 mL/min. Elution linear gradient 0-100% B over 90 min eluent A—10 mM TEA methylphosphonate (pH 3.0) with 80% acetonitrile eluent B—eluent A -I-125 mM sodium perchlorate.] (Reprinted from Ref. 1, p. 186, with permission from Ebevier Science>NL)...

Lockridge et al. Using sodium perchlorate solution of constant or increasing concentration as eluent, the isocratic and gradient chromatography of halide, thiocyanate and thiosulphate with very stable base-line was demonstrated (Fig.3). 

Aqueous salt solutions are corrosive to stainless steel, especially at low pH. When aqueous acetic acid solutions are used as eluent, attention must therefore be paid to corrosion of the HPLC system. However, some salts, such as sodium sulphate, sodium nitrate, sodium acetate and sodium perchlorate, cause little corrosion of stainless steel even at low pH. Accordingly, these salts are a good choice for use together with acetic acid. Salts containing... 

The dihydropyridine derivative arandipine (MPC-1304, Figure 6.44) and its enol tautomer have been analysed using an ODS-modified silica column with methanol-aq. sodium perchlorate (0.36mol L ) (45 + 55) as eluent. Sample preparation was by LLE into toluene and detection was at a GCE (+0.92 V vs Ag/AgCl). Nifedipine was used as the internal standard. A LoD of 0.25 pgL was claimed... 

With direct spectral detection, the detector is set at a wavelength where the sample anions absorb but the eluent cation and anion do not. A number of inorganic anions including nitrate, bromide, iodide, thiocyanate, bromate and thiosulfate, as well as aromatic organic anions, can be detected. Sodium chloride, sodium perchlorate, or a number of other anions could be used in the eluent... 

Figure6.15 Separation ofanions on HPLC column (150 X 4.6 mm) coated with Triton X-100 and then with cetylpyridinium chloride. Eluent 2 mM sodium perchlorate. UV detection at 210 nm. Peaks (1) acetate, (2) nitrite,...

Figure 6.21 Gradient elution with potentiometric detection. Eluent 3.5-10.0 mM sodium perchlorate flow rate,...

The stationary phase shows almost no afSnity for sulfate and very low affinity for chloride, but iodide is strongly retained. An eluent containing 0.2 mM sodium perchlorate was used to elute iodide as a sharp peak in about 6 min. UV detection of iodide at 210 nm was employed. 

The compound hydrolyzes in aqueous solution to form EtHg and thiosalyci-late that is an effective bactericide. Fast analysis of EtHg in less than 4 min can be performed using a bifunctional lonPac CS5A in the microbore format with an eluent consisting of lOmmol/L sodium perchlorate, lOmmol/L acetic acid, and 10 mmol/L cystine at a flow rate of 0.5 mL/min. 

Figure 10.183 Reversed-phase separation of the accelerator and leveler in a used acid copper bath with coulometric detection. Separator column Thermo Scientific Accucore Cl 8, 2.6 (im column dimensions 150 mm x 4.6 mm i.d. column temperature 40 °C eluent (A) water, 2.5 g sodium perchlorate, 2.5 mt of 10% perchloric acid, (B) MeOH, and (C) MeCN/ MeOH (80 20 v/v) with perchlorates as above ...

Eluent. A solution containing 1.175 g (0.01 M) of ammonium perchlorate in 1000ml of methanol adjust to pH 6.7 by the addition of 1 ml of 0.1 M sodium hydroxide in methanol. k Values. Values for drugs in this system will be found in drug monographs and in the indexes to Analytical Data in Part 3 they are also included in the systems for specific groups of drugs which follow. 

Typical stationary phases include the following polyvinylpyrrolidone (PVP) coated silica sorbents, monodisperse non-porous silica columns with surface bound amides or ethers and composite agarose and polyacrylamide gels. The eluent normally consists of salts at concentrations greater than 1.0 M. Typical salts include sodium phosphate, sodium sulfate and ammonium sulfate, and organic acid salts like monosodium glutamate. Protein retention is stronger with salts that increase surface tension like phosphates, sulfates, citrates, which are solvated in water than with salts such as perchlorates and thiocyanates and the like. 

The application of UV alone to monitor substrate oxidation product formation is limited to studies on polyunsaturated fats with conjugated oxidation products. Reverse-phase HPLC elution of conjugated and non-conjugated lipid hydroperoxides (LOOH) can be followed electrochemically (concurrently with UV detection) so long as the eluent contains a supporting electrolyte (such as sodium chloride " or tetraethylammonium perchlorate ). 

Sodium, potassium or ammonium orthophosphate, acetate, perchlorate or citrate salts are commonly used for buffering the eluent and should be of the highest... 

The alkylating agent melphalan (Figure 6.3) has been measured in plasma using a phenyl-modified silica column with acetonitrile-aq. sodium phosphate buffer (0.1 mol L pH 4.5) (6 + 44) as eluent and ED (PGEs, Ei -fO.l V, E2 -1-0.6 V, vs Pd)." Sample preparation involved perchloric acid treatment and LLE into chloroform to remove interferences. No internal standard was used. The LoD was 2 pg L (1 mL sample). 

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