Abstract: Kits, methods, polypeptides, systems, and non-transitory, machine-readable storage media for detecting a nucleic acid in a sample are described. In an embodiment, the kit comprises a loop primer nucleic acid molecule configured for loop-mediated isothermal amplification (LAMP), the loop primer nucleic acid molecule comprising: a targeting sequence complementary to a target portion of a target nucleic acid sequence; and an adapter sequence; a displacement nucleic acid probe comprising: a fluorophore adapter sequence; and the adapter sequence; and a fluorophore adapter complement nucleic acid molecule complementary to the fluorophore adapter sequence, wherein the fluorophore adapter sequence or the fluorophore adapter complement nucleic acid molecule is coupled to a fluorophore. In an embodiment, the system comprises a thermal subsystem for heating a sample disposed therein, and an optical subsystem for optically excited the sample and detecting light emitted from the sample.