Corticosteroids, analysis

Following extraction and cleanup, corticosteroid residues in sample extracts can be determined by thin-layer, liquid, or gas chromatographic methods. Spectrophotometric, fluorometric, electron capture, or mass spectrometric detection systems have all been successfully used in corticosteroids analysis. 

Early applications of thin-layer chromatography in corticosteroid analysis were mainly based on use of phenylhydrazine in sulfuric acid as a spray reagent for derivatization of the analytes (529, 530). Later applications involved use of other spray reagents including phosphoric acid in methanol, tetrazolium blue. 

Most early gas-chromatographic methods for corticosteroid analysis in foods involved use of an OV-17 275 cm column at high temperature and an electron capture detector for separation of the analytes in form of their TMS... 

Valenta, C. Janout, H. Corticosteroid analysis by HPLC with increeised sensitivity by use of precolumn concentration. J.Liq.Chromatogr., 1994, 17, 1141—1146... 

Wade, S.E. Haegele, A.D. Corticosteroid analysis by HPLC-UV facilitated by use of an injector-mounted extraction column. J.Liq.Chromatogr., 1991, 14, 1257-1266 [rabbit serum LOD 300 pg columnswitching column temp 50]... 

Rose, J.Q. Jusko, W.J. Corticosteroid analysis in biologiced fluids by high-performance liquid chromatography. J.Chromatogr., 1979, 162, 273-280 [plasma urine saliva extracted hydrocortisone, prednisolone dexamethasone (IS) LOD 5 ng/mL pharmacokinetics simultaneous beclomethasone, meth-ylprednisolone, trieuncinolone acetonide]... 

J.Q. Rose, and W.J. Jusko, Corticosteroid analysis in biological fluids by high-performance liquid chromatography. J Chromatogr, 163 273 (1979). 

Corticosteroids have been evaluated in several types of cerebral injury, including cerebral infarction. Corticosteroids reduce vasogenic edema, such as that associated with neoplasms, but not cytotoxic edema, the type associated with ischemic stroke. A large meta-analysis found no benefit to the use of corticosteroids in ischemic stroke (or intracerebral hemorrhage), and their use is not recommended, except to treat concomitant conditions that mandate it (e.g., COPD flare). 

E. W. Smith, J. M. Haigh, and R. B. Walker. Analysis of chromameter results obtained from corticosteroid-induced skin blanching I Manipulation of data. Pharm. Res. 15 280-285 (1998). 

Taylor, M. R., Teale, P., Westwood, S. A., and Perrett, D. (1997). Analysis of corticosteroids in biofluids by capillary electrochromatography with gradient elution. Anal. Chem. 69, 2554-2558. 

Taylor, S. and Harker, A. (2006) Modification of the ultrafiltration technique to overcome solubility and nonspecificbinding challenges associated with the measurement of plasma protein binding of corticosteroids. Journal of Pharmaceutical and Biomedical Analysis, 41, 299-303. 

Ishii, D., Hibi, K., Asai, K., Nagaya, M., Mochizuki, K., and Mochida, Y., Studies of micro high-performance liquid-chromatography. 4. Application of micro pre-column method to analysis of corticosteroids in serum. Journal of Chromatography 156(1), 173-180,1978. 

Lipworth BJ. Systemic adverse effects of inhaled corticosteroid therapy. A systematic review and meta-analysis. Arch Intern Med 1999 159 941-55. 

Fast-atom-bombardment (FAB)-Mass spectrometry has been used for the pharmaceutical analysis of corticosteroids [182]. The FAB-mass spectra of 24 corticosteroids (such as cortisone, prednisolone, hydrocortisone, and betamethasone) in were recorded in glycerol and/or thioglyeerol. The... 

System (6) has been described for the simultaneous determination of submicrogram amounts of 17a-deoxy and 17a-hydroxy corticosteroids [145]. Prior to analysis, the corticosteroids were treated with periodic acid in 50% aqueous dioxane, and extracted with dichloromethane. Acylation of the 3- and 17a-hydroxyl groups was carried out using 1 1 butyric anhydride and pyridine. 4- C -cholesterol was added as the tracer, and cholesterol isobutyrate as the internal standard. The column used was glass (8 ft X 5 mm) packed with 1% SE 30 or QF-1 on GasChrom Q (100-120 mesh), and was operated at 250-260°C. Argon (at a flow rate of 30 mL/min) was used as the carrier gas, and detection was by a Sr detector. It was reported that the corticoids could be determined with a precision of approximately 15% down to levels as low as 0.1-0.2 pg. 

System (4) has been described for the analysis of corticosteroids in human adrenal tissues [152]. Prior to the HPLC analysis, the corticosteroids were extracted from adrenal tissues by acetone. The permissible columns were 20 cm X 2.4 mm, consisting of Zorbax-SIL (for more polar compounds) or Zorbax-CN (for less polar compounds). The mobile phase was 9 4 1 cyclohexane-dichloromethane-ethanol or aqueous methanol, and eluted at a flow rate of 0.4 mL/min. Using a UV detection wavelength of 254 nm, sample recoveries were 78.5-99.5%, and the relative standard deviation was 2-5%. 

System (8) has been described for quantitation of corticosteroids as common adulterants in local drugs [156]. The sample is extracted from its matrix by methanol, and the resulting supernatant layer subjected to the HPLC analysis. The column used was an ODS-Zorbax column (25 cm x 4.6 mm), and the mobile phase 7 2 11 acetonitrile-methanol-aqueous 1% phosphoric acid. An eluent flow rate of 0.8 mL/min was used, and the analyte detection was performed using the UV absorbance at 240 nm. The calibration graph was found to be linear in the ranges of 1-15 pg/mL for betamethasone, 0.5-20 pg/mL for prednisolone, and 1-30 pg/mL for cortisone acetate. 

System (1) has been described for the analysis of corticosteroids in urine, and uses HPLC and thermospray LC-MS technology. The method can be... 

An issue for inhaled corticosteroid treatment is patient compliance. Analysis of prescription renewals shows that corticosteroids are taken regularly by a minority of patients. This may be a function of a general "steroid phobia" fostered by emphasis in the lay press over the hazards of long-term oral corticosteroid therapy and by ignorance over the difference between corticosteroids and anabolic steroids, taken to enhance muscle strength by now-infamous athletes. This fear of corticosteroid toxicity makes it hard to persuade patients whose symptoms have improved after starting the treatment that they should continue it for protection against attacks. 

Very few methods have appeared in the literature with respect to the extraction, cleanup, and subsequent determination of corticosteroids in food samples (Table 29.17). Milk analysis usually requires a pretreatment step for fat elimination (527). Centrifugation for 20 min at about 7000 g at 4 C is the usually applied procedure for making the fat floating on the top of the sample. Tissue analysis also requires a pretreatment step for matrix break-up that can be accomplished by means of a mincing and/or a homogenizing apparatus. 

Conn HO, Poynard T. Corticosteroids and peptic ulcer meta-analysis of adverse events during steroid therapy. J Intern Med 1994 236(6) 619-32. 

Richy F, Ethgen O, Bruyere O, Reginster JY. Efficacy of alphacalcidol and calcitriol in primary and corticosteroid-induced osteoporosis a meta-analysis of their effects on bone mineral density and fracture rate. Osteoporos Int 2004 15 301-10. 

Allen DB, Mullen M, Mullen B. A meta-analysis of the effect of oral and inhaled corticosteroids on growth. J Allergy Clin Immunol 1994 93(6) 967-76. 

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