ATP, CTP, GTP, UTP (nucleoside 5´-triphosphate) and 10 mM NTP mixture is suitable for use with SP6, T3 and T7 RNA polymerases work together in in vitrotranscription reactions to generate RNA probes, or RNA transcription for translation in in vitrotranslation extracts. These nucleosides are provided in a convenient, ready-to-use solution at a concentration of 10 mM/1 mM Tris-HCl (pH 7.5).