Radioimmunoassay of Steroids

Radioimmunoassay of Steroids. —6/8-Hydroxycortisol 21-acetate (29) reacted selectively in cold pyridine with carboxymethoxylamine, giving the 3-(0-carboxy-methyl)oxime the 21-acetoxy-group seemingly slows competing reaction with the 20-ketone. The BSA conjugate was used to raise an antibody for the RIA of 6/3 -hydroxycortisol.  

Other steroidal 0-(carboxymethyl)oximes which have been prepared for linkage to BSA include those of 3/3,16a-dihydroxypregn 5-ene-7,20-dione (at C-7), 3-hydroxyoestra-l,3,5(10),7-tetraen-17-one, 3a-hydroxy-5/3-androstan-17-one ( etiocholanolone ), and 17/3-hydroxyandrost-4-ene-3,ll-dione (at C-3). O- 

Compounds described as the 15 -carboxymethyl derivatives (32) of oestrone and oestradiol have been described as haptens, without any evidence as to their configurations at C-15, or their homogeneity. The method of synthesis (via Michael addition of malonic ester to the 15-en-17-one) normally gives 15/8-substituted compounds. Some 15/8-carboxyethylmercaptoandrostane derivatives (33), obtained by addition of methyl 3-mercaptopropionate to androst-15-en- 

17-ones, have also been used in RIA. 3-O-Carboxymethyl ethers of oestrogens have been used as their BSA conjugates to produce antisera with high specificity for ring D substitution type [17-oxo, 17/3-OH, or 16a,17/3-(OH)2]. 7-Carboxy-methyl-androstanes and -pregnanes, prepared from 7-oxo via 7-cyanomethyl derivatives, have also proved useful as haptens.  

Chromatography.—A computer programme has been developed for prediction of the optimum compositions of binary stationary phases for the g.l.c. separation of mixtures of steroids. Problems in the gas chromatography of H- and C-labelled 

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Abraham GE (1974) Radioimmunoassay of steroids in biological materials. Acta Endocrinol (suppl.l83)75 l-42 ErlangerBF, BorekF, Beiser SM, Liebermann S (1957) Steroid-protein conjugate I. Preparation and characterisation of conjugates of bovine serum albumin with testosterone and cortisone. J Biol Chem 228 713-727... 

D. Gupta Radioimmunoassay of Steroid Hormones , Verlag Chemie, Weinheim, 1975. 

K Hoffman, P Samarazeewa, EK Smith, AE Kellie. Radioimmunoassay of steroids, the role of the bridge linking the steroid hapten to the protein carrier. J Steroid Biochem 6 91, 1975. 

A definitive method for stmctural deterrnination is x-ray crystallography. Extensive x-ray crystal stmcture deterrninations have been done on a wide variety of steroids and these have been collected and Hsted (270). In addition, other analytical methods for steroid quantification or stmcture determination include, mass spectrometry (271), polarography, fluorimetry, radioimmunoassay (264), and various chromatographic techniques (272). 

This chapter reviews the year s published work on physical and analytical aspects of steroid chemistry. No attempt has been made to survey the enormous number of routine applications of spectroscopic methods to structure determination. Attention has been concentrated mainly upon those developments of a fundamental nature which increase our understanding of the physical techniques and the phenomena which they explore. The major advances reported this year in the area of spectroscopy lie in the interpretation and applications of Cn.m.r. tritium n.m.r. has made its appearance as a method for the analysis of labelled steroids. The short sections on analytical methods give the Reviewer s selection of significant advances in radioimmunoassay and chromatographic methods of interest to chemists. 

Lacroix C, Fiet J, Benais JP, et al Simultaneous radioimmunoassay of progesterone, androst-4-ene-dione, pregnenolone, dehydroepiandrosterone and 17-hydroxyprogesterone in specific regions of human brain. J Steroid Biochem 28 317-325, 1987... 

Immunoassays (IA) and radioimmunoassays (RIA) are widely accepted and routinely applied for clinical and environmental analyses of steroid hormones, but they have limitations in specificity and accuracy. Therefore, more selective, accurate, and sensitive technologies such as LC-MS/MS and GC-MS/MS methodologies are needed to improve the IA and RIA testing techniques for steroid hormones and... 

Radioimmunoassay (or RIA) was first introduced as an analytical technique in 1959. Since then it has played an increasingly important role in the quantitative analysis of hormones and drugs. Much of the recent rapid progress in endocrinology may in fact be attributed to the availability of this sensitive and accurate method for quantitation of steroidal and pro-tein/peptide hormones. 

D9. Dechaud, H., Lejeune, H., Garoscio-Cholet, M., Mallein, R., andPugeat, M., Radioimmunoassay of testosterone not bound to sex-steroid-binding protein in plasma. Clin Chem. 35, 1609-1614 (1989). 

I, and I. Radioimmunoassay combines the specificity of an immunochemical reaction with the sensitivity of isotope analysis (F4, S19) and is currently developing rapidly for the analysis of steroids, peptide hormones, and specific proteins (G9). Enzymes can be determined with labeled substrates (01). The requirements of standardization and dosimetry make it probable that these methods will continue to be based on relatively large automatic instruments. However, the greatest problems are unlikely to be in the counting equipment but in sample handling and processing and in standardization of the system. 

Hiroi, M. Stanczyk, F. Goebelsmann, U. Brenner, P. Lumkin, M. Mishell, D., Jr. Radioimmunoassay of serum medroxyprogesterone acetate (provera) in women following oral and intravaginal administration. Steroids 1975, 26, 373. 

Radioimmunoassay (RIA) of steroid hormones, a rapidly maturing branch of biochemistry, forms the subject of a monograph.The method depends upon the ability of certain proteins to bind steroids selectively and reversibly ... 

Measurement of steroid sex hormones in serum a comparison of radioimmunoassay and mass spectrometry. Steroids 2002 67 151-8. 

D Rodbard, JE Lewald. In E Diczfalusy, A Diczfalusy, eds. Computer analysis of radioligand assay and radioimmunoassay data. Steroid Assay by Protein Binding. Karolinska Symposia on Research Methods in Reproductive Endocrinology, WHO/ Karolinska Institut, Stockholm, 1970, p 79. 

JPP Tyler, JF Hennam, JR Newton, WP Collins. Radioimmunoassay of plasma testosterone without chromatography A comparison of four antisera, and the evaluation of a novel approach to liquid scintillation counting. Steroids 22 871, 1973. 

C Gomez-Sanchez, L Milewich, OB Holland. Radioiodinated derivatives for steroid radioimmunossay. Application to the radioimmunoassay of cortisol. J Lab Clin Med 89 902, 1977. 

EHD Cameron, JJ Scarisbrick, SE Morris, SG Hillier, G Read. Some aspects of the use of 125I-labeled ligands for steroid radioimmunoassay. J Steroid Biochem 5 749, 1974. 

RMalvano, E Rolleri, URosa. Standardization and control of steroid radioimmunoassays. In Radioimmunoassay and Related Procedures in Medicine, Vol II. Vienna International Atomic Energy Agency, 1974, p 112. 

DEH Llewelyn, SG Hilher, GF Read. The use of multivariable standard curves in the radioimmunoassay of testosterone and 5a-dihydrotestosterone. Steroids 28 339, 1976. 

J Khubieh, et al. Radioimmunoassay of the anticancer agent 4-hydroxyandrostene-dione in body fluids. J Steroid Biochem 35 377, 1990. 

PN Rao, ADI Pena, JW Goldzieher. Antisera for radioimmunoassay of 17a-ethy-nylestradiol and mestranol. Steroids 24 803, 1974. 

The G. interact with specific receptors in the theca and foUicle cells of the ovary and corpus luteum and with the interstitial cells of Leydig in the testes. cAMP is released as a second messenger to stimulate the production of steroid sex hormones. G. can be determined by radioimmunoassay, the radioligand-hormone receptor method, or by biological assays (see Hormones). 

In the original immunoassay of Yalow and Berson (5), the label of choice was a radioisotope and today radioisotopes are still widely used as labels (see The Immunoassay Index I, Lab. Pract. 32(8) (1983) 21), I being the most commonly used. Radioimmunoassay (RIA) has been used extensively in the determination of steroid and peptide hormones, drugs (both for therapeutic monitoring and for the detection of drugs of abuse) and various macromolecules of clinical interest. 

The simulation program Radioimmunoassay on the CD lets you go through the steps that would be involved in selecting an antiserum for radioimmunoassay of a steroid hormone and use the selected antiserum to determine oestradiol in plasma samples. 

Sumner, N.A. (1974) Measurement of anabolic steroids by radioimmunoassay. Journal of Steroid Biochemistry, 5,307. 

Hampl,R.,Picha,J.,Chundela,B.,andStarka,L.(1979)Radioimmunoassay of nortestosterone and related steroids./onma/ of Clinical Chemistry and Clinical Biochemistry, 17,529-532. 

Hampl, R., and Starka, L. Practical aspects of screening of anabolic steroids in doping control with particular accent to nortestosterone radioimmunoassay using mixed antisera. Journal of Steroid Biochemistry, 11, 933-936. 

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