A
label (100, 200, 500, 702, 802, 900, 901, 1000, 1200, 1300, 1600) for analysing a biological sample is provided. The
label (100, 200, 500, 702, 802, 900, 901, 1000, 1200, 1300, 1600) comprises a
nucleic acid backbone (102, 502, 1002, 1102, 1202, 1301) and a first plurality of
labelling moieties (104). The
nucleic acid backbone (102, 502, 1002, 1102, 1202, 1301) has a duplex structure comprising at least 50% of nucleotides of the
nucleic acid backbone (102, 502, 1002, 1102, 1202, 1301). In further aspects a marker (700, 800) comprising the
label and a method for analysing biological samples is provided.