Figure 5.

Chromatogram (A) and product ion mass spectrum (B) of porcine insulin (precursor ion [M+5H]5+ m/z 1156.3) extracted from 2 ml plasma obtained five minutes after IV glucose administration to a STZ-diabetic transplanted rhesus macaque. The retention time and diagnostic product ions derived from the five-fold charged precursor ion unambiguously identify porcine insulin. chromatogram (C) and product ion mass spectrum (D) of human/macaque insulin (precursor ion [M+5H]5+ m/z 1162.3) extracted from 1 ml of non-diabetic rhesus macaque plasma. The retention time and diagnostic product ions derived from the five-fold charged precursor ion unambiguously identify human/macaque insulin. Reproduced with permission (ref. ²).