No. Sorry. Money you spend on your grandchildren is a personal expense and a personal choice. It is not deductible.
You asked about this in another thread but you have in no way indicated that the grandchildren are dependents on your own tax return. If they are your dependents, then if you paid someone to take care of them so YOU can work, you could get the childcare credit. Otherwise, you are just doing what we grandparents do--spending money on the grandkids.