Akademik Veri Yönetim Sistemi
” 53rd TIAFT (The International Association of Forensic Toxicologists) meeting 2015, Florence, İtalya, 30 Ağustos - 04 Eylül 2015, ss.149-150, (Özet Bildiri)
Toxicity of cyanide has been well-documented in the literature. Exposure to cyanide results in adverse health effects in both humans and aquatic biota. People can be exposed to cyanide by variety of ways. Cyanide exhibits its toxic action by binding to the heme-type iron complex in cytochrome oxidase, causing an inhibition in the last step in oxidative phosphorylation in the cycle. Cyanide can also affects the structures many proteins and metalloenzymes. Therefore, determination of cyanide in human biological fluids, especially in blood, is of great importance in forensic identification. We aimed to develop a fast, and reliable sample preparation procedure prior to head space-gas chromatography mass spectrometry analysis for the determination of cyanide concentration in blood samples. Firstly, a 200 μL of 1 M H2SO4 solution was added into a low volume vial insert. This insert containing acid solution was gently placed to bottom of a 22 mL gas chromatography vial. Thereafter, 200 μL of blood sample (or standard solution) were added to dry part of GC vial. After the vial sealed with gas-tight polytetrafluoroethylen (PTFE)-lined rubber septum cap, it was vortexed for 30 seconds. The pretreated sample was then analyzed by HS-GC-MS. The HS-GC-MS conditions were as follows: The headspace oven, needle, and transfer line temperatures were set at 90 ºC, 130 ºC, and 130 ºC, respectively. The injection time was 0.12 min and vial was pressurized to 30 psi in 1.0 min. A Perkin Elmer Elite FFAP (Crossbond Carbowax-PEG for acidic compounds, 30 m × 0.25 mm i.d.) capillary column was utilized. Helium was used as carrier gas. The GC oven temperature was initially set at 40 ºC and held for 8 min, the temperature was increased to 140 ºC at a rate of 10 ºC/min which was held for 3 min, and then elevated to 240 ºC at a rate of 30 ºC/min which was held for 3 min. The temperatures of Electron Impact ion source and GC line were 200 ºC. Repeatability for the peak area and retention time, selectivity, linearity, limit of detection (LOD), limit of quantification (LOQ), and recovery parameters were used for the validation of the analytical method. We obtained excellent RSD (%) values from peak area and retention time of 50 μg/mL cyanide standard solution which were 1.7 and 0.11 (N=10), respectively. Linearity was evaluated by linear regression (R2=0.999). LOD and LOQ were 0.5 μg/mL and 1.5 μg/mL which were calculated from the peak height as the average concentration corresponding to the signal-to noise ratio equal to 3 and 10, respectively. Even though acceptable recovery percentage range is 70–120% with a precision about 20% depending on sample matrix in analytical studies, we obtained perfect recovery values which were 100.5 % for a standard solution and 97.9 % for a blood sample spiked with 50 μg/mL cyanide. In this study, we propose a sample preparation method for headspace GC-MS analysis of cyanide in blood samples. The advantages of the method are easy, fast (max 5 min) and reliable.