Confirmation of de-cellularisation in osteoblast secreted matrices. (A) Light microscopy (scale bar = 100 μm) and SEM techniques were performed following the de-celluarisation of normal matrices. Non de-celluarised osteoblasts are shown as controls. (scale bar: 20 μm). DAPI staining of de-cellularised matrices show no nuclear remnants and non de-cellularised matrices show intact nuclei (scale bar: 50 μm). (B) DNA analysis of the normal osteoblast derived matrices confirmed the removal of nucleic acids in the lysates of de-cellularised matrices. (C, D) Alizarin red staining and the EDX technique were performed to see the mineral content of the normal and OA de-cellularised matrices. All results (from A to D) are representative of matrices produced from four different patients each time with two replicates. Non DCM: Non de-cellularised matrix; DCM: de-cellularised matrix. DAPI, 4',6-diamidino-2-phenylindole; EDX, energy dispersion X-ray; OA, osteoarthritis; SEM, scanning electron microssopy.