Direct analysis of melamine in milk and milk powder

Chromatography of characteristic fragment(m/z 85) from protonated melamine (m/z 127) demonstrating direct determination of milk powder spiked with 6 ng/g melamine (0.06ng melamine in 10 mg milk powder)

 

LTP mass spectrum a) and b) MS/MS product ion spectrum of the protonated melamine 50 ng c), d) sample 0 and 20 ng melamine in 10 mg milk powder e) MS/MS product ion spectrum of the protonated molecule from d)

 

Figure 3 High throughput data for eight control samples (0.5 to 3.0 min) and eight 50 ng/10 mg milk powder samples ((3.5 to 6.5 min) using single reaction monitoring at 170 °C. Inset (left) temperature effect on LTP signal for melamine; inset (right) photograph of the eight samples on a glass slide.

 

Figure S3.a) LTP mass spectrum and b) MS/MS product ion spectrum of the protonated molecule recorded using 5μL raw milk spiked with 5 ng melamine.