No, you can not. multipurpose contact lens solutions require that after you have manually cleaned the lens, you must store it in a clean contact lens case and fill it with saline-based disinfecting solution. Some wearers, to avoid spending more money on contact lens solution, simply top off the old solution after cleaning them again the next day. The chemical agent that disinfects the contact lens loses its potency if not completely replenished with a fresh batch of solution. Bacteria, viruses, fungus and amoebas may not be killed, and are allowed to flourish in that little petri dish.