High performance liquid impurities

J. Ogorka, G. Schwinger, G. Bmat and V. Seidel, On-line coupled reversed-phase high-performance liquid cliromatography-gas chromatography-mass specti ometi y , A powerful tool for the identification of unknown impurities in pharmaceutical products , J. Chromatogr. 626 87-96 (1992). 

Purification of poloxamers has been extensively investigated due to their use in medical applications, the intention often being to remove potentially toxic components. Supercritical fluid fractionation and liquid fractionation have been used successfully to remove low-molecular weight impurities and antioxidants from poloxamers. Gel filtration, high-performance liquid chromatography (HPLC), and ultrafiltration through membranes are among the other techniques examined [5]. 

Ferretti, R., Gallinella, B., La, T.F., Zanitti, L. (1988). Direct resolution of a new antifungal agent, voriconazole(UK-109,496) and its potential impurities, by use of coupled achiral-chiral high-performance liquid chromatography. Chromatographia 47, 649-654. 

The purity of the solid solute also has fundamental analytical implications. In general, the analytical procedure employed for determining the solubility should be specific for the solute of interest. For this purpose, an analyte-specific chromatographic method (such as high-performance liquid chromatography, HPLC) is preferred. Such a method will also enable the impurities and any possible decomposition products to be identified and quantified. 

Penalvo, G. C., Julien, E., and Eabre, H. (1996). Cross validation of capillary electrophoresis and high-performance liquid chromatography for cefotaxime and related impurities. Chromatographia 42, 159-164. 

Reilly, J., and Saeed, M. (1998). Capillary electrochromatography as an alternative separation technique to high-performance liquid chromatography and capillary zone electrophoresis for the determination of drug related impurities in Lilly compound LY300164. /. Chromatogr. A 829, 175-186. 

Jalonen HG (1988) Simultaneous determination of tamoxifen citrate and its E-isomer impurity in bulk drug and tablets by high-performance liquid-chromatography. J Pharm Sci 77 810-813... 

For each dmg substance, the maximum acceptable levels of the various impurities are described in the drug substance monograph or the specification included in the submissions to the regulatory authorities. In this chapter, the ICH Q6A [4] and Q6B [5] definition of specification is used. A specification consists of three parts the test (e.g. moisture content, impurities), references to the analytical procedure (e.g. high-performance liquid chromatography [HPLC], gas chromatography [GC]), and the acceptance criterion (e.g. not more than 0.50%). 

Priestner AA. Use of radiolabeled drug substance to investigate mass balance during validation of a high-performance liquid chromatography method for impurities. Anal Proc 1993 30 374-377. 

Lorenz LJ, Bashore FN, Olsen BA. Determination of process-related impurities and degradation products in cefaclor by high-performance liquid chromatography. J Chrom Sci 1992 30 211-216. 

K. Stella, M. Stella, A. Pandora, A. Morfis, B. Antonios, K. Maria, New gradient high-performance liquid chromatography method for determination of donepezil hydrochloride assay and impurities content in oral pharmaceutical formulation, J. Chromatogr. A 1189 (2008) 392-397. 

Rao RN, Alvi SN and Rao BN, Preparative isolation and characterization of some minor impurities of astaxanthin by high-performance liquid chromatography. J Chromatogr A 1076 189-192 (2005). 

A. G. Butterfield, F. F. Matsui, S. J. Smith, and R. W. Sears, High-performance liquid chromatographic determination of chlor-diazepoxide and major related impurities in pharmaceuticals, J. Pharm. Sci., 66 684 (1977). 

L. Elrod, Jr., C. L. Linton, B. P. Shelat, and C. F. Wong, Determination of minor impurities in temafloxacin hydrochloride by high-performance liquid chromatography, J. Chromatogr., 519 125(1990). 

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