Osteomark® NTx-Urine test is used for the quantitative measurement of cross-linked N-telopeptides of type I collagen in urine. The NTx molecule is bone-specific due to the unique amino acid sequences of the cross-linked alpha-2 (I) N- telopeptide. Release of the NTx molecule is mediated by osteoclasts. Elevated levels of NTx indicate elevated bone resorption.

NTx-levels are used for:

  • monitoring of antiresorptive therapy in individuals diagnosed with osteoporosis
  • monitoring of antiresorptive therapy in individuals diagnosed with Paget’s disease
  • predicting response to hormonal antiresorptive therapy in postmenopausal women

Quick Facts

Range: 20 – 3000nM BCE

Sensitivity: 20nM BCE (value not corrected for creatinine)

Incubation time: 2 hours

Sample volume: 2 x 25µl

Sample type: urine, cell culture

Species: human, dog, porcine, rat, bovine and rhesus macaque


Collect second void of morning urine or 24 hours urine without adding preservatives. Fasting sample collection is not required.

Samples are stable at room temperature for 24 hours or refrigerated at 2-8°C for up to 72 hours. Longer storage at -20°C. Stable up to 3 freeze and thaw cycles.

When monitoring therapy, baseline samples should be collected prior to initiation of therapy. Subsequent specimens for comparison should be collected at the same time of day as the baseline specimen.

nmol Bone Collagen Equivalents/l (nM BCE)

per mmol Creatinine/l = nM BCE / mM Creatinine


Mean Range (± 2 SD)
Premenopausal women (25 – 49 yrs) 35 5 – 65
Men (31 – 87 yrs) 33 3 – 63