EK0540 can be used to detect the rat alveolar bone samples if the concentraion of VEGF in the sample is in the detection range (15.6pg/ml-1000pg/ml) of the ELISA kit. Here is the sample preparation method of general bone tissue for your reference: Extract demineralized bone samples in 4 M Guanidine-HCl and protease inhibitors. Dissolve the final sample in 2 M Guanidine-HCl. The ELISA kit protocol can be found on the datasheet of EK0540, which is downloadable as a PDF on the product's webpage.