Investigation on Fast Determination of Trace N2Nitrosamines Assisted by Microwave Radiation

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1 , ACTA CHIMICA SINICA Vol 60, 2002 No 5, Ξ ( ), NOBr NO x ( x < 2),, CrO 3, NO x ( x < 2) NO 2, 90 %, (TEA) (76 % 96 %) ; 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 ) 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 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 nju edu cn Received August 30, 2001 ; revised December 12, 2001 ; accepted January 8, 2002

2 No 5 : 877 (TEA), (2),, ( ) C 162g 250 ml /,,, N W 0 6 min ; 0 6 g mesh,, ( 1) ; (2) ;, (NPYR), (NDMA) [6 (NHMI) Sigma, Caldwell ],4 (A R ) ;, 1 (TSNA), L/ min Na 2 HPO 4 2 (NNN) (NNK) (NAB) N %,He % 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, 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

3 878 Vol 60, 2002 NO x ( x < 2) NO 2, N NO ( 1 3) 1, 10 %, 2 %, 98 % ; 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 ) / % (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 K,

4 No 5 : 879,,80 % / 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, ( 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 mol) 9 8 %, mol NO, NO mol, N 2 7 % NO NO 2 ( 2 C ) :N ml/ min, 210 s( ) 2 D 210 s ( ) 10-9 mol/ g, 17 h ( ) 10-9 mol/ g ;, [11 ], ;, E D( 2),, / , E [ ( ) 10-9 J, 2450 mol/ g] D [ ( ) 10-9 mol/ MHz, [10 ] g], ; ( 2),,, N NO NO,,,

5 880 Vol 60, 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 s s s s, mg NaNO s, mg NaNO s s h h s s h h 2 79 [12 ] 3 5,, ( 3) ; 1,2,,,, NO,

6 No 5 : 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/ ) :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 (3) Bull 2001, 46, 705 References 1 Eisenbrand, G ; Preussmann, R Arzneimittel Forsch 1970, 20, Walter, C L ; Downes, M J ; Edwards, M W ; Smith, P L R Analyst 1978, 103, Fine, D H ; Rufeh, F ; Gunther, B Anal Lett 1973, 6, Zhu, J 2H ; Yan, D ; Xia, J 2R ; Ma, L2L Chemosphere 2001, 44, 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 (in Chinese) (,,,, 1999, p 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 (A SHEN, H )