Used in bone metabolism research to quantify N-terminal telopeptide fragments of type I collagen in biological samples, serving as a marker for bone resorption. Enables assessment of osteoclast activity and bone turnover rates in experimental models. Commonly applied in studies related to osteoporosis, metabolic bone diseases, and evaluation of anti-resorptive therapies. Provides a sensitive and specific method for monitoring changes in bone degradation under various treatment conditions.