Is there an OTC kit for testing vitamin D levels? ("Serum concentration of 25(OH)D is the best indicator of vitamin D")

Can someone make one of those nifty little bio-chip things (do those exist?) that is connected to a little needle thing like electronic insulin monitors?

There are companies that sell kits where you collect a blood sample at home, and then mail it in for analysis (except in NY, which apparently bans medical tests by mail).

Two examples:

http://www.zrtlab.com/vitamindcouncil/

http://www.amazon.com/gp/product/B004BYURTU/ref=as_li_ss_tl?...

Not aware of the actual analysis equipment being available in a consumer-level product, though.

I don't know. Would like to know as well. Anyone?