Biphasic calcium phosphate nanoparticles comprising both hydroxyapatite (HA) and beta polymorph of tricalcium phosphate (beta-TCP) have been synthesized together by a polymer matrix mediated process. The process, based on in situ mineralization of poly (vinyl alcohol), exerts a good control over the morphological features of biphasic nanoparticles. By controlling the reaction chemistry (Ca:P ratios), nanobioceramic particles having three different HA/beta-TCP ratios of 50:50, 55:45 and 60:40 respectively. As the two constituents of biphasic system (HA and beta-TCP) facilitate series of signaling cascades in osteoblast division and differentiation, the adhesion and differentiation properties of mesenchymal cells (MSCs) derived from bone marrow has been studied.