The present disclosure describes compositions of matter comprising a ribonucleoprotein complex comprising a nucleic acid-guided nuclease and a guide RNA, and further comprising a blocking nucleic acid molecule represented by Formula IV, wherein Formula IV in the 5′-to-3′ direction comprises: T-D-M-A-Lp-C; wherein T is 17-31 nucleotides in length; D is 0-15 nucleotides in length; M is 1-25 nucleotides in length; A is 0-15 nucleotides in length and comprises a sequence complementary to D; and L is 3-25 nucleotides in length; p is 0 or 1; C is 4-15 nucleotides in length and comprises a sequence complementary to T; and wherein the blocking nucleic acid molecule comprises a sequence complementary to a gRNA.