The first impression is a lasting impression... go with the business attire, not the nursing attire (if that's what you mean by work attire).
I have been on both sides of the interview process, and have seen applicants interview in scrubs
, suits, and even a t-shirt/shorts. The interview panels I've been a part of have ALWAYS commented on the ones who dress in scrubs/casual wear as not being serious about wanting the job compared to the more professionally-dressed applicants. This is usually the first comment made after the interviewee has completed his or her interview and left the room, so this first impression does not go unnoticed even if they gave a stellar verbal interview. I know it may seem a bit nitpicky, but competition is tough for nursing jobs. You have to give an impression that you *want* that job, and that also boils down to how well you present yourself.
Anyway, this is a perspective from a mid-sized city in Texas with five hospitals within it.