Supporting Information Determination of 135 Cs and 135 Cs/ 137 Cs atom ratio in environmental samples by combining AMP selective Cs adsorption and ion-exchange chromatographic separation to triple quadrupole inductively coupled plasma mass spectrometry Jian Zheng 1*, Wenting Bu 1,2, Keiko Tagami 1, Yasuyuki Shikamori 3, Kazumi Nakano 3, Shigeo Uchida 1, and Nobuyoshi Ishii 1 1 Research Center for Radiation Protection National Institute of Radiological Sciences 491 Anagawa, Inage, Chiba 263-8555, Japan Fax: 0081-43-255-0721 2 State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, China 3 Application Center, Agilent Technologies Japan, Ltd., Takakura, Hachioji, Tokyo, 192-8510, Japan Number of pages in Supporting Information Section: 7, including cover Number of Tables in Supporting Information Section: 2 Number of Figures in Supporting Information Section: 5 Corresponding author *Phone: +81-43-206-4634. Fax: +81-43-255-0721. Email: jzheng@nirs.go.jp 1
Sample solution before AG MP-1M separation 133 Cs 96 Mo 138 Ba Cs fraction after AG MP-1M separation 133 Cs 96 Mo 138 Ba Fig. S1 Anion-exchange resin (AG MP-1M) for the separation of Mo from Cs and Ba in IAEA-375 soil reference material. Detection of Mo, Cs and Ba in the sample solution was conducted using SF-ICP-MS. 2
Soil Plant Ash (450 ºC, 2h) Digestion (20mL conc. HNO 3 ) Filtration Adjust HNO 3 to 1.6 M, add 35mg AMP, stir for 1 h 0.45 µm syringe filter Column precondition with 10 ml water and 10 ml 1.5 M NH 3 H 2 O 2 ml AG MP1 5 ml 1.5 M NH 3 H 2 O Cs elution Mo, Sb, Snretain in resin Cs, Ba pass through Cs fraction, evaporate to dryness, dissolve in 5 ml 0.15 M NH 3 H 2 O Column precondition with 10 ml 1.5 M HCl and 10 ml H 2 O, then 10 ml 0.15 M NH 3 H 2 O 2 ml AG 50 WX8 Cs, Ba separation 10 ml 0.15 M NH 3 H 2 O rinse 10 ml H 2 O rinse 30 ml 1.5 M HCl elution Cs fraction Evaporate, dissolve in 2 ml 4% HNO 3 for ICP-MS/MS measurement Fig. S2. Flow chart of the developed analytical procedure for the determination of 135 Cs and 137 Cs isotopes in environmental samples by AMP Cs adsorption combining a two-stage ion-exchange chromatographic separation and ICP-MS/MS detection. 3
Fig. S3 Effect of N 2 O (20%) gas flow rate on the signal intensities of 119 Sn 16 O + and 121 Sb 16 O +. Experimental conditions of triple quadrupole ICP-MS/MS: He gas flow rate, 1 ml/min; Q1 m/z 135, Q2 m/z 135 for 119 Sn 16 O + signal intensity; Q1 m/z 137, Q2 m/z 137 for 121 Sb 16 O + signal intensity. 4
Fig. S4 Autoradiography of litter samples collected in Fukushima Prefecture at location 1 (S1) and location 3 (S3) in May 2011; and on the Chiba NIRS campus in December 2013. Heavy deposition of radioactive cesium can be seen in S3 litter. 5
Fig. S5 Comparison of 137 Cs activities in Fukushima environmental samples measured by gamma spectrometry and ICP-MS/MS. 6
Table S1 Optimized analytical conditions of the triple quadrupole ICP-MS/MS Plasma RF power (W) 1550 Sampling position (mm) 8 Plasma gas flow rate (L min -1 ) 15 Auxiliary gas flow rate (L min -1 ) 0.9 Nebulizer pump (rps) 0.1 Spray chamber temperature ( 0 C) 2 Nebulizer gas flow rate (L min -1 ) 0.8 Makeup gas flow rate(l min -1 ) 0.21 Lens Extraction lens 1 (V) 0 Extraction lens 2 (V) -190 Omega bias (V) -105 Omega lens (V) 8 Q1 entrance (V) -6 Q1 exit (V) 1 Cell focus (V) 5 Cell entrance (V) -50 Cell exit (V) -60 Deflection (V) 4.8 Plate bias (V) -60 Cell He flow rate (ml min -1 ) 1 N 2 O (purity 20 %) flow rate (ml min -1 ) 3 OctP bias (V) -5 OctP RF (V) 170 Energy discrimination (V) -7 Measurement Integration time (sec) 1 for m/z = 97, 119, 121, 133 and 138 5 for m/z = 135, 137 Table S2 Comparison of different sorbents for the adsorption of Cs and interfering elements* Sorbent Cs (%) Ba (%) Mo (%) Sb (%) Sn (%) AMP 99.2 ± 1.2 12.0 ± 0.8 --- 0 16.7 ± 11.0 AMP-PAN 98.7 ± 0.3 18.6 ± 6.6 --- 0 20.7 ± 5.9 KNiFC-PAN 100.0 ± 0.6 21.1 ± 4.0 0 0 60.0 ± 0.6 *AMP and AMP-PAN contain large amounts of Mo, thus the comparison of Mo adsorption was not conducted for these two sorbents. 7