Research Areas



  • Assay Type Competitive ELISA
  • Sample Types Extracted Serum, Extracted Plasma, Urine, Fecal Extracts
  • Sensitivity 1.85 pg/mL
  • Species 11-Ketotestosterone is identical across species
  • Assay Duration 2.5 Hours
  • Samples/Plate 39 in duplicate
  • Readout Colorimetric, 450 nm
  • Standard Curve
  • Description

    Assay Principle: 

    The 11-Ketotestosterone ELISA Kit quantitatively measures 11-Ketotestosterone in urine, extracted plasma, extracted serum, and dried fecal extracts. The 11-Ketotestosterone ELISA Kit is a competitive ELISA with a run time of 2.5 hours. Please read the complete kit insert for more information before performing this assay.

    Use our provided 11-Ketotestosterone standard to generate a standard curve for the assay. Pipette the standards or diluted samples into a transparent microtiter plate coated with our goat anti-rabbit IgG antibody. Add the 11-Ketotestosterone peroxidase conjugate and the 11-Ketotestosterone polyclonal rabbit antibody. Then incubate the mixture covered at room temperature, shaking for 2 hours. The immunological reaction occurs between the anti-11-Ketotestosterone polyclonal antibody, the 11-Ketotestosterone antigen in the sample or standard, and the 11-Ketotestosterone-peroxidase conjugate. As the 11-Ketotestosterone concentration in the sample increases, the bound 11-Ketotestosterone-peroxidase conjugate decreases, causing a decrease in signal and vice versa. 

    After the 2-hour incubation, wash away the excess 11-Ketotestosterone-peroxidase and add the TMB substrate. The TMB substrate reacts with the bound 11-Ketotestosterone-peroxidase conjugate generating a signal detected by a plate reader at 450nm. Use the intensity and the standard curve to calculate the 11-Ketotestosterone concentration in the samples.


    Androgenic hormones, such as testosterone, affect many male organisms’ growth, size, and reproduction. In teleost fish, along with testosterone, 11-ketotestosterone plays a significant role by inducing reproductive characteristics in both males and females. In particular male fish, 11-ketotestosterone levels increase during spermatogenesis in the spawning season, while in some female fish, 11-ketotestosterone increases before yolk deposition to regulate ovarian development.

    The presence and involvement of 11-ketotestosterone in other species, such as humans, have only recently been established. In contrast to fish, primate serum 11-ketotestosterone concentrations were not significantly different in males and females, despite males having significantly higher circulating testosterone. This evidence suggests that 11-ketotestosterone production in these species may not be testis-dependent and primarily originates from adrenal-derived 11-oxyandrogen precursors. Recent studies have discovered more 11-ketotestosterone than its precursors, androstenedione, and testosterone, in prepubertal children and postmenopausal women compared to men. This discovery highlights the potential use of 11-ketotestosterone as a clinical biomarker to screen adrenal androgen excess in disease conditions such as polycystic ovary syndrome (PCOS) and hirsutism in women.

  • Structure