Biomarker Reference · Free T
Free Testosterone (by Equilibrium Dialysis) (Free T) is a clinical biomarker used in male-hormones assessment. Free testosterone is the small unbound fraction — roughly 1–2% of total — that is not attached to SHBG or albumin and is directly available to tissues. It is measured in 1 laboratory test on BiomarkersLabs.com.
Free testosterone is the small unbound fraction — roughly 1–2% of total — that is not attached to SHBG or albumin and is directly available to tissues. Equilibrium dialysis physically separates the free fraction across a semipermeable membrane before quantification, which is why it is regarded as the reference method. It is independent of binding-protein concentration, unlike total testosterone.
Directly measured free testosterone by equilibrium dialysis is the most reliable index of bioavailable androgen, particularly when SHBG is abnormal — as in obesity, insulin resistance, ageing, thyroid disease, hepatic disease, or oestrogen exposure — where total testosterone can be misleading. It is materially more accurate than analogue immunoassay free testosterone, which is unreliable and should not be used, and it avoids the assumptions inherent in calculated free testosterone.
Reference ranges vary by laboratory and assay platform. Interpret in context of the issuing laboratory's stated range.
1 test on BiomarkersLabs.com include this biomarker.
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