Free Testosterone Saliva ELISA Kit


Human free testosterone saliva ELISA kit is an accurate in vitro quantitative method for detecting unconjugated free testosterone (17beta-hydroxy-4-androstene-3-one) in human saliva samples. This assay has a minimum sensitivity detection limit of 2.2 pg/ml.


Testosterone is a C19 steroid hormone that is mainly produced in the leydig cells of the testes of males and in smaller quantities formed in the ovaries of females. It is known to play vital functions during the development of the male reproductive tissues, bone mass, hair growth, sexual function, supporting increased muscles, stamina, cardiovascular health and the general well-being of the immune system. The determination of testosterone has been useful in diagnosing and treating disorders that involve androgens. These include primary or secondary hypogonadism, disorders originating from testicular problems, defects of the hypothalamus and pituitary glands. Other disorders are impotence in males, virilization (masculinization) due to tumors, hirsutism (excessive hair) in females, adrenogenital syndroms and polycystic ovaries.

In both males and females a large quantity of testosterone is produced from the conversion of circulating androstenedione, DHEA and DHEA-S. It also displays a diurnal rhythm where the highest levels are seen in the morning and the lowest around midnight. Generally adult males usually have around 10-20 fold higher testosterone plasma concentrations present when compared to females. During circulation it is found that the main part of testosterone is bound to plasma proteins for example sex hormone binding globulin (SHBG) and albumin. Only a small portion approx. 1-2 % of the testosterone is unbound or free, this represents the biologically active form. In the cells a large quantity of this hormone can be converted to 5a-dihydrotestosterone, the free testosterone can also be released via the salivary glands. There is a direct correlation between the level of testosterone in saliva and the level of free testosterone present in plasma. This salivary testosterone ELISA kit is only specifically designed to be used for saliva samples.

So far, every attempts for a direct quantification of free testosterone using either serum or plasma samples with a commercial immunoassays has failed. The only reliable alternative is using salivary samples to measure it, there have been many publication which have proved that the analysis of free testosterone using saliva provides clinically valid results even when the concentrations being measured are quite low. Also, using salivary methods it is easier to compensate for the episodic secretion pattern by carrying out multiple sampling over a given period of time. A mixture of these sample can then be used to carry out the analysis procedure, whereas only using single saliva sample per analysis will give arbitrary results, similar to those obtained for serum and plasma samples.


All reagents supplied need to be stored at 2 °C – 8 °C, unopened reagents will retain reactivity until expiration date. Do not use reagents beyond this date.

  • Microtiter Plate (96 Wells): Coated with rabbit polyclonal anti-testosterone antibody.
  • Calibrator 0.
  • Calibrators 1-5: Concentrations 10, 30, 100, 300, 1000 pg/ml, made up from human testosterone.
  • Control 1 (Low) and Control 2 (High).
  • Enzyme Conjugate: Consisting of testosterone conjugated to horseradish peroxidase.
  • Substrate Solution: Tetramethylbenzidine (TMB).
  • Stop Solution: Contains 2 N hydrochloric acid solution.
  • Wash Solution (10x Concentrated).


The minimum sensitivity detection limit of human free testosterone using current salivary testosterone ELISA kit was approximately 2.2 pg/ml. The dynamic range for this assay is 10.0 – 1,000.0 pg/ml.


– Free Salivary Testosterone (Free Testosterone Saliva): ELISA
– Analytical Sensitivity: 2.2 pg/ml
– Specificity (Cross Reactivity): Testosterone (100%), 5α-Dihydrotestosterone (23.3%), Androstenedione (32.2%).
– Assay Dynamic Range: 10 – 1000 pg/ml.
– Intra-Assay Variation: 7.9 – 9.9%
– Inter-Assay Variation: 7.9 – 9.9%
– Recovery: 80.4 – 116.0%
– Linearity: 74 – 117%


  1. Assessing biological maturity: chronological age and the pubertal development scale predict free testosterone in adolescent males. J Pediatr Endocrinol Metab. (2015) 28 (3-4): 381-6. Hibberd E.E., et al.
  2. Analytical Evaluation of Free Testosterone and Cortisol Immunoassays in Saliva as a Reliable Alternative to Serum in Sports Medicine. J Clin Lab Anal. (2016) 30 (5): 732-5. Lippi G., et al.
  3. Relationships between salivary free testosterone and the expression of force and power in elite athletes. J Sports Med Phys Fitness. (2012) 52 (2): 221-7. Crewther B.T., et al.
  4. A critical evaluation of salivary testosterone as a method for the assessment of serum testosterone. Steroids. (2014) 86: 5-9. Fiers T., et al.


  • Full Name: Free Testosterone Saliva ELISA Kit
  • Reactivity: Human
  • Sample Type: Saliva
  • Sensitivity: 2.2 pg/ml



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