2002 60 5, 876 881 ACTA CHIMICA SINICA Vol 60, 2002 No 5, 876 881 Ξ ( 210093), NOBr NO x ( x < 2),, CrO 3, NO x ( x < 2) NO 2, 90 %, (TEA) (76 % 96 %) ; 2 10-8 mol/ L /,, 3 min, ( ),, Investigation on Fast Determination of Trace N2Nitrosamines Assisted by Microwave Radiation XU, Yang ZHU, Jian2Hua 3 SHEN, Bin XUE, Jun ( Department of Chemistry, Nanjing University, Nanjing 210093) Abstract The spectrophotometric determination of trace N2nitrosamines in solution was investigated in order to enhance its recovery and sensitivity Based on the investigation on the recovery below 10 % in this method, the reason was found relating to formation of spectrophotometric invisible NO x ( x < 2) species such as NO Consequently an oxidation tube was added in the instrument to convert these NO x species into the detectable NO 2, therefore the recovery for N2nitrosamine with concentration of 2 10-5 2 10-8 mol/ L could be increased to 80 % 98 %, close to that of thermal energy analyzer (76 % 96 %) On the other hand, resulting from the discovery that many N2nitrosamines could be evaporated under microwave radiation, a new method combining microwave radiation with the improved spectrophotometric method was thus reported for determining both N2nitrosamines and nitrogen oxides in tobacco and tobacco products Within 3 minutes both N2nitrosamines and nitrogen oxides in tobacco or tobacco products could be collected for detection Keywords microwave radiation, spectrophotometric method, N2nitrosamines, NO x, tobacco, (TEA) [3 ], /,TEA, /, 1970, [1 ], [2 ], ;, 1973, Ξ E2mail :jhzhu @netra nju edu cn Received August 30, 2001 ; revised December 12, 2001 ; accepted January 8, 2002
No 5 : 877 (TEA), (2),, ( ) C 162g 250 ml /,,, N 2 850 W 0 6 min ; 0 6 g 20 40 mesh,, ( 1) ; 1 1 1 (2) ;, (NPYR), (NDMA) [6 (NHMI) Sigma, Caldwell ],4 (A R ) ;, 1 (TSNA), L/ min Na 2 HPO 4 2 (NNN) (NNK) (NAB) 1 1 1 N 2 99199 %,He 99 999 % 2 2 CrO 3 [4 ] 1 5 A C ; 2 1 D(C1F, 3 ) E(C3F, 2 ), N N NOBr, 1 cm 1 mm GC/ MS [5 ] (3) NO x, 16 250 ml ( 1), HBr/ HAC NO 2 WP850D ( [1,4 ], 850 W) ( 2), 85 % (1) 2 L 5 % 2 U,, NOBr,, N 2 ; [2 NO NO x ( x < 2) ; NO ] [4 ], 4 CrO 3, 1 Figure 1 Schematic of apparatus for the determination of N2nitrosamines and NO x in tobacco by use of microwave radiation a microwave oven ; b container ; c zeolite in glass tube ; d traps for absorption of N2nitrosamines ; e trap for absorption and determination of NO x
878 Vol 60, 2002 NO x ( x < 2) NO 2, N NO ( 1 3) 1, 10 %, 2 %, 98 % ; 10-5 10-8 mol/ L -, 80 %, TEA (76 % 96 %) [7 ] 3 : 10-5 mol/ L, 0 5 % ; 10-8 mol/ L, 3 5 %, 2 1, N N O Figure 2 Recovery of N2nitrosodiphenylamine in ( NDMA TSNA NNN spectrophotometric method via flow rate of carrier gas NNK ), ( 69 % 98 % 101 % 105 %) ; [8 ] ( ) (in the case of no CrO 3 oxidation tube used) NDMA NYPR NHMI TSNA 1 ( 200 ml/ min) Table 1 Analysis on the trace amount of N2nitrosamine by use of spectrophotometric method / CH 2 Cl 2 ( %) - (mol L - 1 ) ( CrO 3 ) ( CrO 3 ) / (mol L - 1 ) / % 2 5 10-5 98 0 0 3 4 6 10-7 68 9 1 7 10-5 98 7 1 1 3 7 10-7 83 7 1 3 10-5 99 6 0 6 6 7 10-5 88 9 2 2 10-8 101 0 8 0 1 7 10-7 105 0 3 (a) 10-5 mol/ L, (b) 10-8 mol/ L Figure 3 Recovery of N2nitrosamines in the different concentration by use of the improved spectrophotometric method (a) concentration of the solution is 10-5 mol/ L, (b) concentration of the solution is 10-8 mol/ L 2 2 / ( 593 K [9 ] ), 20 %( (2450 MHz, 850 W) 2 3 ) ( 4) NPYR, NHMI NNN, min 333 353 K,
No 5 : 879,,80 % / 30 40 s, 10 % NO x ( x 2) (1) 10 % ( 5), 4 (2) ( 850 W) Figure 4 Decomposition of N2nitrosamines under microwave radiation in a sealed system (The power of microwave radiation was 850 W) 5 (850 W) (NPYR NHMI) (1) (2) (3) Figure 5 Distribution proportion of N2nitrosamines under the microwave radiation (850 W) of 35 s (1) decomposed ; (2) remained ; (3) evaporated GC/ MS, 6,NaY ( m/ z = 18) ( m/ z = 32) ; 573 K NO ( m/ z = 30), N 2 O (CH 3 ) 2 N + ( m/ z = 44), N 2 ( m/ z = 28), NH + CH + 3 ( m/ z = 15), m/ z 41, 58, 78 91 ( 6a) ; NaA ( 6c) / [9 ; ], NNN NPYR MS, NO NO 2 10 ( 2 A B), N NO NO [11 ], NO 2 C, (9 7 mg NaNO 2 0 14 10-3 mol) 9 8 %, 13 8 10-6 mol NO, NO 2 0 09 mol, N 2 7 % NO NO 2 ( 2 C ) :N 2 200 ml/ min, 210 s( ) 2 D 210 s (1 96 2 04) 10-9 mol/ g, 17 h (1 43 1 56) 10-9 mol/ g ;, [11 ], ;, E D( 2),, / 2 10-22, E [ (3 12 3 18) 10-9 J, 2450 mol/ g] D [ (1 96 2 04) 10-9 mol/ MHz, [10 ] g], ; ( 2),,, N NO NO,,,
880 Vol 60, 2002 6 - Figure 6 The MS spectrum of zeolite (a,b) NaY and (c,d) NaA adsorbed in the tail2gas follow of tobacco (a) NaY, adsorbed after microwave radiation and evacuated at 573 K; (b) NaY, adsorbed before microwave radiation and evacuated at 573 K; (c) NaA, adsorbed after microwave radiation and evacuated at 773 K; (d) NaA, adsorbed before microwave radiation and evacuated at 773 K 2 - ( 850 W) Table 2 Detection of tobacco samples by use of microwave2spectrophotometric method (with the microwave power of 850 W) (10-9 mol/ g) A B C D E (10-9 mol/ g) NO NO 2 35 s 2 48 11 4 0 8 35 s 3 31 42 4 1 8 210 s 2 81 61 7 1 2 210 s 2 61 88 2 2 6 210 s, + 9 7 mg NaNO 2 2 58 13 800 90 1 210 s, + 9 6 mg NaNO 2 2 54 13 779 96 8 210 s 2 04 10 8 210 s 1 96 10 9 17 h 1 56 17 h 1 43 210 s 3 12 13 6 210 s 3 18 13 6 17 h 2 84 17 h 2 79 [12 ] 3 5,, ( 3) ; 1,2,,,, NO,
No 5 : 881 3 - Table 3 The detection of the amount of N2nitrosamine and NO x in the tobacco samples by use of microwave2spectrophotometric method (10-9 mol/ ) (mg/ ) (10-9 mol/ ) 1 12 1 2 3 13 3 20 21 4 2 11 1 0 2 96 2 62 13 5 3 15 1 3 6 65 3 00 110 4 4 13 0 9 5 62 2 52 126 7 5 8 0 6 4 76 2 50 143 7 :850 W, 210 s 3 (,,,,, 2001, (1) 17, 696 ) NOBr, NO x ( x < 2) ; Chem 1990, 73, 783 CrO 3 NO x ( x < 2) NO 2, 90 % (2) /, Scientific Publication, No 9, Lyon, France, 1974, p 242 243 (3) Bull 2001, 46, 705 References 1 Eisenbrand, G ; Preussmann, R Arzneimittel Forsch 1970, 20, 1513 2 Walter, C L ; Downes, M J ; Edwards, M W ; Smith, P L R Analyst 1978, 103, 1127 3 Fine, D H ; Rufeh, F ; Gunther, B Anal Lett 1973, 6, 731 4 Zhu, J 2H ; Yan, D ; Xia, J 2R ; Ma, L2L Chemosphere 2001, 44, 949 5 Xue, J ; Zhu, J 2H ; Shen, B ; Ma, L2L Acta Phys 2 Chim Sin 2001, 17, 696 (in Chinese) 6 Caldwell, W S ; Conner, J M J Assoc Off Anal 7 Rhee, M S Acta Tabacaria Sinica 1999, 5,12 (in Chinese) (,, 1999, 5, 12 ) 8 Fine, D H International Agency for Research on Cancer 9 Zhu, J 2H ; Shen, B ; Wang, Y ; Yan, D Chin Sci 10 Jin, Q 2H Microwave Chemistry, Science Press, Beijing, 1999, p 5 147 (in Chinese) (,,,, 1999, p 5 147 11 Xu, H 2X N2Nitroso Compounds in Environment, Science Press, Beijing, 1988 (in Chinese) (, N2,,, 1988 ) 12 Leaf, C2D ; Wishnok, J 2S ; Tannenbaum, S2R Carcinogenesis ( London) 1991, 12, 537 (A0108303 SHEN, H )