It was working and controlling the OP's BP. Use the info on it and then you would be able to locate more of it at other pharmacies. Also the bankrupt pharmacy should have records of what was issued. I doubt that any sophmore style chem student would have access to the equipment needed to assay it. You have to get the actual procedure that the manufacturers use to certify their product. IMO there is something amiss with what the new pharmacy is providing. Start there and tell them what you found. Take an old empty bottle with you.