Direct ultramicro determination of estradiol

A modified method for ultramicro analysis of estradiol [E2] in pharmaceutical preparations and biological fluids was described in this study. The method depended on the use of alkaline phosphatase conjugate and magnetic separation of the free and bound fractions followed by direct colorimetric measurement. The sensitivity was 40 pmol/L and the range was 0.04-8 nmol/L. Coefficient of variation [CV] ranged from 1.1 to 4.2% for intra- and 1.3 to 5% for inter-assay. The method was applied for analysis of E2 suspension and determination of serum E2 level after local cream application. It correlated well with the BP 93 and radioimmunoassay [RIA] methods [r=0.96 and 0.94]

Non isotopic assays for tumor markers as a monitor for treatment

Tumor markers [cancer embryonic antigen [CEA], alpha fetoprotein [AFP] and cancer antigens 50, 125 [CA 50 and CA 125] serum levels] were measured by time resolved fluoro and enzyme immunoassays [TRFIA and EIA] in 40 cases of carcinoma of the ovary and uterus. While, rechecking the precision of the non isotopic methods, the coefficient of variation [CV] ranged from 7.7 to 9.4% for CEA and 7.8 to 11.4% for CA 125. Analytical recovery was 97.8% and 95.6%, sensitivity was 0.2 ng/ml and 3 u/ml and the correlation coefficient [r] with RIA was 0.96 and 0.94, respectively. The assays were repeated three months after treatment. A statically significant rise was found in the levels of CEA, AFP and CA 125 before treatment as compared with a control group. A significant drop in the levels occurred in serum CEA, AFP and CA 50 levels in cases of ovarian malignancy and in serum CA 125 in cases of ovarian and uterine malignancy after the three months treatment

Determination of ultramiro-quantities of estriol in pharmaceutical preparations by two modified methods

A new methodology for ultramicro-determination of estriol [E3] in pharmaceutical preparations has been studied. No prior extraction is needed for the developed alkaline phosphatase method. The coefficient of variation [CV] was 13.5%, while that of a modified chemiluminescent [CL] method was 9.2%. Analytical recovery was 91.0% and 98.638%, respectively. Both methods correlated well the United States Pharmacopoeia [USP], and the conventional radioimmunoassay methods. The correlation coefficients [r] were 0.9, 0.89, 0.92. Levels of estriol and its ester, after a single injection, were determined and CL assay was more sensitive. The limit of detection [ED 50] was 100 pmol/L and 900 fg/tube, respectively. The developed method using alkaline phosphatase is void from the need of expensive equipment but still needs further improvement in precision. The modified CL method is time saving and provided an alternate to chromatographic assays for ultramicroanalysis of estriol in pharmaceutical preparations

Microdetermination of progesterone and testosterone in pharmaceutical preparations

A new method has been developed for the determination of micro- quantities of progesterone and testosterone in pharmaceutical preparations. The method does not involve prior extraction and showed an acceptable precision. The steroid is coupled with alkaline phosphatase linked to specific antibody, then free and bound fractions are separated by a magnetic technique and chromagen is added, followed by colorimetric measurement. The overall coefficient of variation [CV] was <10% for the 2 steroids. Analytical recovery was 98.7% for progesterone and 98.1% for testosterone. The results were valid and accurate, and the method correlated well with the British Pharmacopoeial method [BP] and radioimmunoassay [RIA] technique. Correlation coefficients were 0.97, 0.96, 0.95 and 0.91, respectively. The assay could be applied for determination of these drugs as single or batch samples using a simple colorimeter and magnetic separator

Modified methods for direct assay of levonorgestrel and prolactin levels during two monthly injections

Modified radioimmunoassay [RIA] and chemiluminescence [CL] methods were adapted for ultra-micro determination of levonorgestrel [L- Nog] and prolactin [PRL] in biological fluids. No prior extraction was needed. The methods yielded precise results with coefficient of variation of < 10%. The methods correlated well with USP XXIII and the conventional RIA methods. The correlation coefficients [r] were 0.92, 0.94 for L-Nog and 0.91 for PRL. The sensitivity of modified RIA for L-Nog was 100 Pmol/L. Modified CL method for PRL showed excellent sensitivity [0.04 ng/ml]. Modified methods were applied to quantitate L-Nog and PRL serum levels during two monthly L-Nog injection. The modified analytical techniques provided accurate, precise, time saving and sensitive methods for analysis of L-Nog and PRL serum levels

Determination of some levels of glucose and some minerals during treatment with injectable contraceptives

Serum sodium [Na], potassium [K], total calcium, iron and glucose levels, during two monthly injections of levonorgestrel [L-Nog] and norethisterone enanthate [NET-EN] were determined. Ion selective electrode potentiometric method for analysis of Na and K yielded more precise results than flame photometry. The intra- and intercoefficients of variation [CV] ranged from 0.5 to 1.1%, 0.6 to 1.9%, 0.6 to 1.9% and 2.0 to 2.3% for Na and K, respectively. Modifications of ferrozine method for analysis of serum iron were introduced. The modified method correlated well with reference bathophen-anthroline method, correlation coefficient [r] was 0.95. Precision was acceptable, intra- and inter CV ranged from 2.1 to 3.4% and 2.6 to 3.9%, respectively. Linearity was kept up to 2500 mug/dl, recovery was 98.8% +/- 1.4 and sensitivity was 20 mug/dl. The only significant change in the studied serum minerals and glucose levels was an increase in iron level, which was beneficial. The modified ferrozine method proved to be an accurate and reliable method for serum iron analysis

Direct fluoroimmunoassay of salivary estradiol in sequential clomiphene citrate-gonadotropins therapy

Serum and salivary estradiol [E2] levels in 26 females, during clomiphene citrate-gonadotrophins therapy for ovarian stimulation, were measured by direct fluoroimmunoassay [FIA]. There was a good correlation between E2 concentrations in serum and saliva samples as well as between levels measured with and without prior extraction of the saliva [r = 0.75 and 0.94, respectively]. The mean ratio of salivary to serum E2 levels was 2.2% +/- 0.25. The salivary E2 level reached a pre-ovulatory peak on day 12, and a second luteal phase peak on day 18 of the stimulated cycle [concentrations were 127 +/- 13 and 77 +/- 8 pmol/L, respectively]. The noninvasive nature of saliva collection in multiple sampling regimens, coupled with non-isotopic FIA for measuring salivary E2 levels, could serve as a useful tool for monitoring follicular response to any therapeutic ovarian stimulation scheme

approach to the application of non isotopic labels for immuno-assays of hormones

Labelled reagent methods of hormones have played an increasingly important role in reproductive endocrinology. Binding assays in which enzyme conjugate replace the conventional radioactive labels have advantage of the relatively long shelf life of the conjugate, low costs, and lack of radiation hazards. This work aims to represent a preliminary study on the validity of non isotopic immunochemical techniques for the assay of some hormones. Leucotropin [LH] was determined by enhanced chemiluminescence [CL] using acridine ester as a label and magnetized antibodies. Both LH and human chorionic gonadotrophin [HCG] were analyzed by time resolved fluoro-immunoassay [FIA] using europium ion as a label. The two techniques yielded results that correlated well with the conventional radio-immunoassay [RIA]. Progesterone was analyzed by enzyme immunoassay technique immunochemical technique [EIA]. The results obtained agreed with the results of RIA indicating the high specificity of the method