wort for yeast starter

I dont have access to DME for use in yeast starters, but i really want to start doing yeast starters from yeast that iv harvested. So i collected about 2 gallons of end runnings from an AG brew i did yesturday. Its pretty weak so im boiling it down and iv put a couple cups of dextrose in. I plan on putting it into a few 1 pint mason jars and using it for starter material. Im also going to use some yeast nutrient when i actually do the starters. So im just wondering if anyone has ever done this.