A polynucleotide sequencing method comprises (i) removing a label and a blocking moiety from a blocked, labeled nucleotide incorporated into a copy polynucleotide strand that is complementary to at least a portion of a template polynucleotide strand; and (ii) washing the removed label and blocking moiety away from the copy strand with a wash solution comprising a first buffer comprising a scavenger compound. Removing the label and blocking moieties may comprise chemically removing the moieties. The first buffer may also comprise an antioxidant and may be used in a scanning buffer used during a nucleotide detection step.