Testosterone ELISA Kit

Intended Use

For in-vitro research use. The testosterone ELISA KIT is to be used for quantitative determination of testosterone levels in serum.

Introduction

Testosterone is one of the major important male sex hormone for maintenance of secondary sex characteristic, accessory sexual organs and libido. It is primary secreted in to the circulation by leydig cells of the testis in the male, thecal cells of the graffian follicle in the female under the influence of luteinizing hormone from pituitary and by adrenal cortex in both.

Major part about 98% of testosterone is present in circulation bound to sex–hormone binding globulin with high affinity and to albumin with lesser affinity.

Principle Of The Assay

The ELISA of testosterone is a competitive solid-phase assay. Serum samples or standards along with testosterone-horseradish peroxidase (T-HRP) enzyme conjugate and testosterone-antibody (T-Ab) are incubated in second antibody coated wells. After incubation, the liquid contents of the wells are decanted, and the wells are washed under running tap water for removing the unbound enzyme conjugate. The bound enzyme activity is measured by developing colored product from colorless substrate after incubation. The quantity of color developed is directly related to the bound enzyme conjugate and is inversely related to the concentration of analyte. Unknown values are determined by interpolation from the standard curve

10,000.00

Reagent Provided

Reagents are stable until the expiry date of the kit, if stored at 2-8°C.

  • T-HRP enzyme conjugate (7 mL), ready to use.
  • Secondary-Ab coated –96 wells (8 well strip) ready to use.
  • T-Ab (2.5mL), ready to use.
  • Eight standards (each vial with 0.5 mL of standards), ready to use. The concentration of Testosterone ranges from 0 to 40ng/mL with 0.03% Proclin 300. The exact concentration is marked on each vial.
  • TMB/H₂O₂ solution (12 mL), ready to use.
  • Stop solution (12.0 mL 0.5 M H₂SO₄)

Materials Required But Not Provided

In addition to standard laboratory equipment the following items are required

  • Precision micropipette (100 µL – 1000 µL)
  • Precision micropipette (10 µL – 100 µL)
  • ELISA – Reader (Microtiter Plate Reader)

Precautions

For satisfactory results:

  • Do not mix reagents from different lots
  • Let reagents come to room temperature before use
  • All blood components and biological materials should be handled as potentially hazardous. Decontaminate and dispose specimens and all potentially contaminated materials as they could contain infectious agents.

    Sample Collection

    Collect the blood in plain tube, separate the serum from cells by centrifugation. Store at 2-8oC, if the assay is to be performed within 24 hours. For longer storage keep frozen at – 20o C or – 8Oo C after aliquoting so as to avoid repeated freezing thawing.

    Assay Procedure

    Let reagents come to room temperature.

    • Secure the desired number of coated wells in the holder.
    • Dispense 50µL of standard or unknown serum samples, into appropriate wells in duplicate.
    • Dispense 50µL of testosterone-HRP enzyme conjugate into each well.
    • Dispense 20µL of testosterone-antibody into each well.
    • Incubate for 60 minutes at room temperature.
    • After incubation remove the mixture by flicking the plate contents into a waste container.
    • Fill and flick the microtiter wells 7-10 times under running tap water.
    • Tap the plate 15 to 20 times on a cloth towel and ensure that water has been removed from wells.
    • Dispense 100 µL of substrate solution in each well.
    • Incubate at room temperature for 15 minutes.
    • Stop the reaction by adding 100µL of stop solution.
    • Read OD at 450 nm with a microtiter well reader immediately.

    Summary Of Assay Procedure

    Results

    Testosterone concentration in samples are obtained from the standard curve.

    • Standards curve (sigmoid in nature). Plot standard curve on semi- logarithmic paper. Optical density or % A/Ao on the vertical axis. The testosterone standard concentrations (ng/mL) on the horizontal axis.
    • ii) Obtaining of testosterone concentration in samples: For each sample, locate the OD or %A/Ao on the vertical axis and read of the corresponding testosterone concentration on the horizontal axis. It will directly show the concentration in terms of ng/mL in serum.

      Ao = optical density at zero dose
      A = optical density at varying concentrations of standard dose or unknown sample
      % A/Ao = A/Ao X 100

    Example Of Testosterone Standard Curve

    Specfic Performance Characteristics

    • a) Sensitivity: The minimum concentration of testosterone, which can be detected from 0 standard, is 0.25 ng/mL (B0-2SD)
    • b) Intra-assay and inter-assay variation: The precision profile of the assay was determined from 5 quality control serum samples. The results were –
    • c) Accuracy: For recovery study, different concentrations of testosterone were added to serum sample wherein its basal concentration was already estimated. The recovery performance of the assay is given below.
    • d) Specificity: The cross-reactivity of this antibody is less than 0.1% with naturally occurring C27, C21, C19, and C18, except nandrolone 2.46%, androstenediol 0.66%, and 5 α –dihydrotesto sterone 9.66%.
Quantity

Kit