Comparative Osteoinductive Potential of BMP-2, Bioactive Glass, and Demineralized Bone Matrix: An In Vitro Alkaline Phosphatase Assay Study

<sec><title>Background</title> The rising number of spinal fusion procedures has increased the demand for effective bone graft substitutes. Although recombinant human bone morphogenetic protein-2 is clinically used for its osteoinductive properties, dose-dependent complications limit its broader application. Demineralized bone matrix (DBM) and bioactive glass (BAG) are alternative materials, but their comparative and combined osteogenic potential remains unclear. This study evaluated the in vitro osteoinductive activity of BMP-2, DBM, BAG, and a composite nano-BAG + DBM formulation. </sec><sec><title>Methods</title> An in vitro C2C12 alkaline phosphatase (ALP) assay was used to assess osteogenic differentiation following exposure to BMP-2 (50 ng/mL) and test materials at 20 and 50 mg/mL. Gel-based formulations were standardized to 1 g total weight and included the following: nano-BAG + DBM (33:33:33 of cortical DBM, 45S5 BAG, and porcine gelatin; marketed as NanoFuse DBM), BAG + Gel (50:50 BAG and gelatin), and DBM + Gel (50:50 DBM and gelatin). Wet/frozen DBM (100% DBM) served as the native reference. ALP activity was measured at 410 nm and normalized to total protein content. </sec><sec><title>Results</title> Wet/frozen DBM exhibited the highest ALP activity (>94.420 units/mg protein), followed by nano-BAG + DBM at 50 mg/mL, which exceeded the assay’s upper detection limit (>92.473 units/mg). DBM + Gel showed moderate activity, while BAG + Gel and the negative control showed minimal induction. BMP-2 at 50 ng/mL demonstrated lower activity (31.700 units/mg) than nano-BAG + DBM. </sec><sec><title>Clinical Relevance</title> NanoFuse DBM demonstrated dose-dependent osteoinductive activity and may offer a safer, more efficient alternative to BMP-2 and traditional grafts in spinal fusion, trauma, and joint reconstruction. </sec><sec><title>Conclusions</title> NanoFuse DBM demonstrated dose-dependent osteoinductive activity and outperformed DBM, BAG, and BMP-2 at the tested dose. These findings support its potential as a bone graft substitute in spinal fusion and other orthopedic applications where improved biological performance and safety are critical. Further research is needed to optimize BMP-2 dosing and evaluate NanoFuse DBM’s in vivo efficacy. </sec><sec><title>Level of Evidence</title> 5. </sec>