Indirect photometric chromatography

Yokoyama, Y. and Sato, H., Performance of some commercial UV detectors for indirect photometric chromatography, /. Chromatogr. Sci., 26, 561, 1988. 

Figure 26-8 Indirect spectrophotometric detection of transparent ions. The column was eluted with I mM sodium phthalate plus 1 mM borate buffer, pH 10. The principle of indirect detection is illustrated in Figure 26-30. [Reproduced tram H. Small, Indirect Photometric Chromatography, Anal Chem. 1982,54,462]...

Various Amines Showing Retention Times and their Detection Limits by Indirect Photometric Chromatography... 

Sithole, B. B. and Guy, R. D., Determination of alkylamines by indirect photometric chromatography. 

H. Small andT. E. Miller, Jr., Indirect photometric chromatography. Anal. Chem., 54, 462,1982. 

UV detection may also be performed indirectly. This method is called indirect photometric chromatography (IPC). Introduced independently by Small et al. [65] and by Cochrane and Hillman [66] in 1982, a UV-absorbing eluant is utilized for the determination of UV-transparent ions. In case of anion analysis, the anion exchanger being used is equilibrated with a UV-active eluant Na E . According to Fig. 7-35 (A), a constant signal at the detector ouflet is observed at a constant flow rate and an appropriate absorption wavelength. If a sample Na S ... 

A practical method for low level perchlorate analysis employs ion chromatography. The unsuppressed method using a conductivity detector has a lower detectable limit of about 10 ppm. A suppression technique, which suppresses the conductivity of the electrolyte but not the separated ions, can further improve sensitivity (110,111). Additionally, ion chromatography can be coupled with indirect photometric detection and appHed to the analysis of perchlorates (112). 

Shamsi, S. A. and Danielson, N. D., Ion chromatography of polyphosphates and polycarboxylates using a naphthalenetrisulfonate eluent with indirect photometric and conductivity detection, /. Chromatogr. A, 653, 153, 1993. 

Wang and Yang [261] used liquid chromatography with indirect photometric detection to determine down to 0.8pg triorganotin compounds in non saline waters. 

Takeuchi et al. [343] described an indirect photometric detection method for anions in micro high performance liquid chromatography. Micro anion exchange octadecylsilica columns permanently coated with the hydrophobic cetyltrimethylammonium ion (cetrimide) were used in the high performance liquid chromatography of chloride, nitrate... 

Ion chromatography can be used to measure ionic concentrations in solution. It requires a fairly large amount of solvent and usually a suppressor column to neutralize the acidity prior to detection by conductivity. For analytical purposes, most analyses previously performed by ion chromatography are now performed using capillary electrophoresis. However, Katagi et al. used ion chromatography with indirect photometric detection to analyze for nerve agents and hydrolysis products in human serum (8). 

Katagi, M., Nishikawa, M., Tatsuno, M and Tsu-chihashi, H. Determination of the main hydrolysis products of organophosphorous nerve agents, methylphosphonic Acids, in human serum by indirect photometric detection ion chromatography, J. Chromatogr., B, 698, 81 (1997). 

Interestingly a crystal violet dye was used as a IPR for indirect photometric detection. Common inorganic anions were separated and detected at the absorption maximum of the dye with classical reversed phase columns. The affinity of the analytes decreased in the order of 8203 > 804 > I" > N03" > Br > N02 > CL, which is the same as that observed with classical anion exchange chromatography [136]. 

R. Thompson, N. Grinberg, H. PerpaU, G. Bicker, and P. Tway, Separation of organophosphonates by ion chromatography with indirect photometric detection, /. Liq. Chrom. 17 (1994), 2511-2531. 

In its broadest sense, selectivity has also been achieved through the development of ion chromatography and indirect photometric detection. Apart from opening up a completely new application of HPLC these provide highly selective techniques for the analysis of inorganic and organic ions. 

The principle of indirect photometric detection can also be applied to ion-pair chromatography provided the counter ion of the ion-pair reagent exhibits the respective absorption properties. For example, A-methyloctylammonium-p-toluenesulfonate was utilized as the ion-pair reagent to analyze chloride and sulfate [32] upon application of indirect photometric detection. The corresponding chromatogram is shown in Fig. 6-18. 

Another important application of the redox system cerium(III)/cerium(IV) is indirect fluorescence chromatography (IFC) of alkali- and alkaline-earth metals. As with indirect photometric detection (IPC), an eluant with a high background... 

K. Ohta. Ion chromatography with indirect photometric detection of common mono- and divalent cations using an unmodified silica gel column and tyramine/oxalic acid/18-crown-6 as eluent. Analytica Chimica Acta 405 277-284,2000. 

Chalgeri A, Tan HSl (1993) Assay of citrate in pharmaceutical matrices by indirect photometric liquid chromatography. Pharm Biomed Anal 11 353-359... 

Eppert, G., G. Liebscher, Factors influencing the resolution of positionally isomeric alkane monosulfonates in reversed-phase ion-interaction chromatography with indirect photometric detection, J. Chwmatogr. Sci., 1991,29,21-25. 

---