Having a specific certification could be that one thing that makes you stand apart from the rest. If you don't have any certifications just relay to the interviewer that it is something you'd like to work towards shortly. By letting the interviewer know that you have future goals related to education, it will tell them that you are a motivated person. Interviewers love motivated people!
"I do not currently hold any specific certifications, aside from my associate's degree in biomedical technology but I'm currently studying for my Laboratory Equipment Specialist Certification. I plan to test in 3 months."
"I am certified to work on Laboratory Chemical Analyzers. I'd love the opportunity to become certified on the larger equipment you have in your facility. Do you recommend any particular certifications to help me be more successful in this role?"
"In addition to my Biomedical Engineering degree, I have taken specialized coursework on autoclaves and sterilization equipment, electrophoresis products, and vortex mixers. Is there a specific certification for which you are seeking? I do not recall seeing one mentioned in your job posting."