Used in biomedical research to quantify levels of rat type I collagen alpha-1 chain in tissue extracts, serum, plasma, and cell culture supernatants. Helps assess extracellular matrix remodeling in studies related to fibrosis, wound healing, bone regeneration, and connective tissue disorders. Commonly applied in preclinical studies involving liver, kidney, lung, and cardiovascular tissues to monitor disease progression or response to treatment. Provides a reliable, sensitive, and specific measurement method for collagen I expression in rat models.