Step 5一Dilution refolding-The solubilized glargine insulin analog protein is thendiluted into refolding buffer (20 mM Glycine, pH 10-11 at 6-100C.) to a final concentration of1.5 mg/ml and permitted to refold for 24 to 72 hours, preferentially about 48 hours, at 6-100C.Higher protein concentration may be used in the refold if desired, however, overall refoldefficiency will decrease. Sodium Chloride and Phosphate are then added to final concentrationsof 700 mM and 25 mM respectively, followed by pH adjustment to 7.0 to 9.0, preferably 7.9-8.0with 6M HCI.