Figure 1. Accurate Quantity and High Quality Listeria monocytogenes DNA Standard. Two micro-liters of Norgen’s Listeria monocytogenes Quantified Bacterial DNA Standard and various serial dilutions (blue curves) were used in a 20 µL Listeria monocytogenes-specific PCR reaction using Norgen’s 2X PCR Master Mix (#28007), supplemented with SYBR Green I. The real-time PCR reactions were performed on a Bio-Rad CFXReal-Time PCR System. No template controls with water were also performed (yellow curves). Norgen’s Listeria monocytogenes Quantified Bacterial DNA Standard and various serial dilutions showed consistent amplification down to fewer than 40 copies per reaction.