abstract |
The invention concerns a modified base of formula:n norn n, wherein dNTP represents any triphosphate deoxynucleotide. The invention also relates to conjugate of formula (A-X) n -B, wherein A is a peptide tag molecule of known molecular weight, X is a linker that is cleaved during sample desorption/ionization, n is an integer superior to 1 and B is a nucleic acid probe with a sequence complementary to a target mRNA molecule, wherein the nucleic acid probe comprises at least one modified base according ot the invention. The invention further relates to a method for determining at least one target mRNA molecule map in a tissue section, comprising the use of the conjugate. |