sentences:  Additionally, SELEX has been utilized to obtain highly specific catalytic DNA or DNAzymes.Several metal-specific DNAzymes have been reported including the GR-5 DNAzyme (lead-specific), the CA1-3 DNAzymes (copper-specific), the 39E DNAzyme (uranyl-specific)  and the NaA43 DNAzyme (sodium-specific).These developed aptamers have seen diverse application in therapies for macular degeneration and various research applications including biosensors, fluorescent labeling of proteins and cells, and selective enzyme inhibition.