Department of Legal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu 431-3192, Japan.
Anal Bioanal Chem. 2012 Jun;403(7):1793-9. doi: 10.1007/s00216-012-5848-3. Epub 2012 Feb 28.
A rapid method was developed to identify and quantify the azide ion (N(3)(-)) in gastric fluid and urine. N(3)(-) in diluted biological fluids was reacted with NaAuCl(4) to produce Au(N(3))(2)(-), which was extracted with octanol. Five microliters of the extract were flow-injected into an electrospray ionization tandem mass spectrometric instrument. Quantification of N(3)(-) was performed by selected reaction monitoring of the product ion Au(N)(N(3))(-) at m/z 253, which was derived from the precursor ion Au(N(3))(2)(-) at m/z 281, using 50 μL of aqueous solution within 10 min. This method was found to be linear up to 10(-5) M, to have a limit of quantification of 10(-7) M, a limit of detection of 3.0 × 10(-8) M, and a coefficient of variation of ≦10% at 10(-7) M. In the case of urine, 50 μL of urine were spiked with N(3)(-), this was diluted 10-fold and passed through 1 mL of a resin, and finally diluted to 100-fold of the original. This method was linear up to 10(-3) M, had a limit of quantification of 10(-5) M, a limit of detection of 3.0 × 10(-6) M, and coefficient of variation of ≦8.8% for an original urine concentration of 10(-5) M. The practical applicability of this method was checked by diluting 1 μL of a suspected suicide victim's gastric fluid 20,000-fold and 1 μL of the victim's urine 5,000-fold and then measuring the N(3)(-) levels. These levels were found to be (7.5 ± 1.0) × 10(-2) M and (3.2 ± 0.4) × 10(-3) M, respectively.
一种快速鉴定和定量检测胃液和尿液中叠氮离子（N(3)(-））的方法。将稀释后的生物体液中的 N(3)(-)与 NaAuCl(4)反应，生成 Au(N(3))(2)(-)，然后用正辛醇萃取。将 5μl 萃取液注入电喷雾串联质谱仪。通过对前体离子 Au(N(3))(2)(-)（m/z 281）衍生的产物离子 Au(N)(N(3))(-)（m/z 253）进行选择反应监测，定量检测 N(3)(-)。使用 50μL 水溶液，在 10min 内可检测到浓度高达 10(-5) M 的 N(3)(-)。方法的线性范围为 10(-5) M 至 10(-3) M，定量限为 10(-7) M，检出限为 3.0×10(-8) M，10(-7) M 时变异系数≤10%。对于尿液，将 50μL 尿液中加入 N(3)(-)，将其稀释 10 倍，通过 1mL 树脂，最后将体积稀释至原始尿液的 100 倍。该方法在 10(-3) M 至 10(-5) M 范围内呈线性，定量限为 10(-5) M，检出限为 3.0×10(-6) M，原始尿液浓度为 10(-5) M 时，变异系数≤8.8%。通过将疑似自杀者的胃液稀释 20,000 倍和尿液稀释 5,000 倍，然后测量 N(3)(-)水平，检验了该方法的实际适用性。结果分别为（7.5±1.0）×10(-2) M 和（3.2±0.4）×10(-3) M。
