1 INTENDED USE Competitive immunoenzymatic colorimetric method for the quantitative determination of DHEA-S concentration in saliva.

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1 1 INTENDED USE Competitive immunoenzymatic colorimetric method for the quantitative determination of DHEA-S concentration in saliva. 2 PRINCIPLE DHEA-S (antigen) in the sample competes with horseradish peroxidase DHEA-S (enzyme-labelled antigen) for binding onto the limited number of anti-dhea-s (antibody) sites on the microplate (solid phase). After incubation, the bound/free separation is performed by a simple solid-phase washing. The enzyme substrate (H 2 O 2 ) and the TMB-Substrate (TMB) are added. After an appropriate time has elapsed for maximum color development, the enzyme reaction is stopped and the absorbances are determined. DHEA-S concentration in the sample is calculated based on a series of standard. The color intensity is inversely proportional to the DHEA-S concentration of in the sample. 3 REAGENTS, MATERIAL AND INSTRUMENTATION 3.1 Reagent and material supplied in the kit 1. DHEA-S Standards S0 (1 bottle) 1 ml S1 (1 bottle) 1 ml S2 (1 bottle) 1 ml S3 (1 bottle) 1 ml S4 (1 bottle) 1 ml 2. Incubation Buffer (1 bottle) 30 ml Phosphate buffer 3. Conjugate Stock Solution (1 bottle) 0.4 ml DHEAS-HRP conjugate 4. Coated Microplate (1 microplate) Anti-DHEAS IgG adsorbed on microplate 5. TMB-Substrate (1 bottle) 12 ml H 2 O 2 -TMB 0.25 g/l (avoid any skin contact) 6. Stop Solution (1 bottle) 12 ml Sulphuric acid 0.15 mol/l(avoid any skin contact) 3.2 Notes Store all reagents between +2 C and + 8 C in the dark. Open the bag of reagent 4 (Coated Microplate) only when it is at room temperature and close immediately after use. The microplate, once opened, it stable until expiry date of kit. Do not remove the adhesive sheets on the unused strips 3.3 Reagents necessary which are not supplied with the kit Distilled water. DRG International, Inc., USA Fax: (908) corp@drg-international.com 1

2 3.4 Auxiliary materials and instrumentation Automatic dispenser. Microplates reader Sample tubes, e.g. DRG SALI-TUBES (SLV-4158) 3.5 Preparation of reagents Standard (S0, S1, S2, S3, S4) Before use, mix for 5 min. with rotating mixer The standards have the following concentration of DHEA-S: S0 S1 S2 S3 S4 ng/ml After opening stable at +4 C until the expiration date of the kit. Diluted Conjugate (Prepare immediately before use!) Add 10 µl stock solution (reagent 3) to 1.0 ml of Incubation Buffer (reagent 2).Mix gently. Stable for 3 hours at 18 C 25 C. 4 PREPARATION OF SAMPLES The determination of DHEA-S can be performed in saliva. Sample collection: The patient should not eat, drink, chew gum or brush teeth for 30 min before sampling. Otherwise rinse mouth thoroughly with cold water 5 min prior to sample collection. Do not collect samples when oral diseases, inflammation or lesions exist (blood contamination). Saliva can be collected in a suitable sampling device. Due to the high adsorption characteristics of some steroids at certain material we strongly recommend the use of the special DRG SALI-TUBES (SLV-4158). A minimum of 0.5 ml liquid should be collected. Saliva flow can be stimulated by chewing on a piece of Parafilm. It is recommended to freeze samples at 20 C prior to laboratory testing. After thawing, mix and centrifuge 10 min at x g to remove particulate material. Take care that the saliva samples are visually okay (no reddish color indicating blood contamination). Do not use sample collector commercially available as SALIVETTE. Other sample collectors commercially available have not been tested. Store the sample at 2 C to 8 C for one week. For longer period samples should be frozen at -20 C. 4.1 Precaution Maximum precision is required for reconstitution and dispensation of the reagents. This method allows the determination of DHEA-S from 0.2 ng/ml to 12 ng/ml. The clinical significance of the determination DHEA-S can be invalidated if the patient was treated with cortisone or natural or synthetic steroids. DRG International, Inc., USA Fax: (908) corp@drg-international.com 2

3 5 PROCEDURE As it is necessary to perform the determination in duplicate, prepare two wells for each of the five points of the standard curve (S0-S4), two for each sample, and one for Blank. Pipette: Mix well. Sample - 50 µl - Standards S0 S4 50 µl - - Diluted Conjugate 150 µl 150 µl - Incubate at 37 C for 15 minutes. Remove the contents from each well; wash the wells with 300 µl of distilled water. Repeat the washing procedure by draining the water completely. Pipette TMB-Substrate 100 µl 100 µl 100 µl Incubate at room temperature (20-25 C) for 15 minutes in the dark. Pipette: Stop Solution 100 µl 100 µl 100 µl Read the absorbance (E) at 450 nm against Blank. 6 STANDARD CURVE - CALCULATION OF RESULTS 6.1 Mean absorbance and relative percentage Calculate the mean absorbance (Em) corresponding to the single points to the standard curve and of each sample. Express data as the percentage of the mean absorbance of B0 (EmS0) with the following formula: Em (B/B0)% = x 100 (Em S0) 6.2 Standard curve Plot the values of the standards expressed as (B/B0)% on the enclosed logit-log paper. Extrapolate the line passing through the points. DRG International, Inc., USA Fax: (908) corp@drg-international.com 3

4 6.3 Calculation of results Interpolate the values of the samples expressed as (B/B0)% on the standard curve to obtain the corresponding values of the concentrations expressed in ng/ml. 7 REFERENCE VALUES As the values of salivary DHEA-S have a circadian pattern we suggest to collect the samples at the same hour (8 A.M.): The following values can be used as preliminary guideline until each laboratory established its own normal range. WOMAN MAN ng/ml ng/ml 8 PERFORMANCE CHARACTERISTICS 8.1 Specificity The cross reaction of the Coated Microplate calculated at 50% according to Abraham are shown in the table: DHEA-S 90.0 % DHEA % Androsterone-S-Na 48.0 % Androstenedione 20.0 % Etiocholanolone-S-Na 0.2 % 5α Androstandione 0.01 % Testosterone 0.01 % Progesterone 0.01 % 17α OH-Progesterone 0.01 % Estrone 0.01 % Cortisol % Cholesterol % 8.2 Sensitivity The sensitivity of this method, calculated as two times the S.D. from B0, is 25 pg/ml when the value of (B/B0)% is approx 90%. 8.3 Precision The inter and intra-run precision had a coefficient of variation of 3.7% and 5.6% respectively. 8.4 Accuracy The recovery of ng/ml of Dehydroepiandrosterone Sulphate added to a sample gave an average value (± SE) of 102.1% ± 4.6% with reference to the original concentrations. 8.5 Correlation with serum sample Correlation with a serum sample of the same patient: r = 0.78 n = 43 p < DRG International, Inc., USA Fax: (908) corp@drg-international.com 4

5 9 WASTE MANAGEMENT Reagents must be disposed off in accordance with local regulations. 10 BIBLIOGRAPHY 1. Abraham G.E., Maroulis G.B., Buster J.E. Chang R.J. and Marshall J.R. (1976). Effect of Dexamethasone on Serum Cortisol and Androgen Levels in Hirsute Patients. Obstet. Gynecol., 47 (4), Granoff A.B. and Abraham G.E. (1979). Peripheral and Adrenal Venous Levels of Steroids in Patients with Virilizing Adrenal Carcinoma. Obstet. Gynecol., 53 (1), Hopper B.R. and Yen S.S.C. (1975). Circulating Concentration of Dehydroepiandrosterone and Dehydroepiandrosterone Sulphate During Puberty. Journal of Clinical Endocrinology Metab. 40 (3), Winter J.S.D., Frainam C. and Reyes F.I. (1978). Normal and Abnormal Pubertal Development Clinical Obstetic and Gynecol., 21 (1), D. Riad - Fanny, G.F. Read, R.F. Walker and K. Griffiths. Endocr. Reviews, vol. 3 N 4 (1982) DRG International, Inc., USA Fax: (908) corp@drg-international.com 5