I don't know specifically for MS, but worked professional jobs for 5 years, so I'm a bit familiar with that kind of wardrobe. (I give my MS caveat because each environment is a little different.) However, for every environment that I've been in, the nice truth about women's clothes is that it's somewhat easy to fudge...
For example, I love the fact that there are shirts that are not button down but have a collar. So they can kind of substitute. There are also mock sweater/collared shirt combos where it's just a sweater, but has collar and cuffs of a collared shirt sewn into it so it looked like you've layered one beneath.
There are also slack you can get that do not need ironing. Some are made of fabrics that don't wrinkle (I can't remember the fabric name that I'm thinking of...it's something like varicose, but not quite that😛) so they keep their iron lines forever. Others are just made of a nice looking fabric and have the crease lines sewn into them. They're basically just pants, but look more dressy because of that crease line addition.
I'm sure I have more tricks up my sleeve on how to look dressy but not really be that dressed up, but I can't think of them right now. I'll go take a look at my closet for some ideas.
But mostly, in my experience, dress shirts need ironing, so it's best if you can avoid them! (I always wore a shell or some other shirt and then a jacket over it because you can wear almost anything that looks halfway decent (no tshirts or text, of course) for a shell. But you may not want to wear jackets to class necessarily. Though I do recall that Gap or J Crew or someone had some cute vaguely business looking (though more casual) jackets a while back, and those might be nice.
Oh, and one more thing that I can think of...for pants, even dress pants...get ones with some stretch. Makes sitting for 8 hours (whether at a desk job or in lecture hall) much much more comfortable. Stretch is in everything these days, even dress/professional clothes!