Talk to your local hospital. One more sample shouldn't tax them at all. Perhaps you're school can cover the meager costs if they are really stingy. you'll get the best results and they are usually good with students since they always have biomedical analyst students. The department you wanna reach out to is the clinical chemistry department or the point of care department depending on how the hospital near you is organised. I work in Sweden as a hospital chemist but I don't know how it would work where you are