I dip a soft bristled toothbrush in 70% isopropyl alcohol
I do the same, but use 99.9% Anhydrous isopropyl alcohol. Airdries really quick. I have a gallon bottle of this http://www.digikey.com/product-detail/en/mg-chemicals/824-500ML/473-1150-ND/2602438 that I refill a taller version of this with http://www.digikey.com/product-search/en/static-control-esd-clean-room-products/accessories/2228308?k=isopropyl and a hog hair brush, the longer bristles fit nicely over the legs of shields. http://www.digikey.com/product-detail/en/mg-chemicals/857/473-1050-ND/949492
Does smell like a doctor's/vet's office afterwards.