Xác định đồng thời dư lượng kháng sinh nhóm nitrofuran trong một số loại thực phẩm tươi sống trên địa bàn hà nội bằng phương pháp sắc ký lỏng khối phổ LC MS MS

ng th
nitrofuran trong mt s loi thc ph
si b
sng khi ph LC/MS/MS


Trn Th Hng


i hc Khoa hc T 
Lu ThS.  ; : 60 44 29
ng dn:  Hng Ho
o v: 2012


Abstract. Gii thiu v ng c
c ph
dnh ng thi 4 cht chuya nitrofuran trong thc
ph  ng bng LC-MS/MS. ng d       t
chuya nitrofuran trong thc ph







 , ,
u kt qu c.

Keywords. ; ; Thc phm

Content
M U

 sinh thc phn  c c c bi 
th c hi b n trong thc
phm khin lo ngi. c sn xu
 cu v c qu dng
thung lng s dt b tr 
tin. T  li tn phi
ngn sc kh
ng hc s dng trong th
u tr d u tr nh nhim
i Escherichim.
c s d u tr nhi
ng thy si cho sc khc bi
 t bin  i     ng cht chuy  a
nitrofuran trong s ng lu t gia cng thy sn phm nhp
kh mt s khu vc Nam M. T n
lnh cm s dng trong sn xut thc phng vt ti nhiu quc gia bao gm M, Canada
t lnh ct c i thc phm nhp kh
u gii hn nh nht cn thc hin
 i vt chuy [29]
2002,  Vit Nam, B nh cm sn xut, nhp
kh dng mt s lot trong sn xuh
TACN t].
Hin nay vic s d mng nh
ng ti sc khng vy vi nhu cu bc thit v v m bo
VSATTP hi     nh

ng tht s loi thc phng
i bng khi ph LC/MS/MS.


NG QUAN

1.1. Gii thiu v 
t ng h

 -nitroc s
d ng, ch yi vm,
lnng thy sn (, ) 

u tr 
nhilmonella spp, gia cm
bnh t u [12].
 itrofuran  Furazolidone, furaltadone, furazolidone,
nitrofurazone, 





 










 (AOZ,
AMOZ, AHD, SEM) 

 





[12].
1.2. ng ct 








1995, 0 ch ra rp cht
  tt chuyt trong
.
V m t chuy

y
 th i cht  vi khun. D  



sinh sc nng tt vi vi khung th
ng c vng vt, mt s cht 






[7].


 thp, nitrofuran  ng dit
khun.
Theo nhing rt t





 salmonellosis,
ng. Trn nitrofuran vi thc
 l 

ng nhanh.
Nitrofuran n sc kht bin [7], khi

















.








 









. , 
















 



 [9u gii hn nh
nht cn thc hii vt chuy
29].




c phm
T  


n trong  gia cm
n phng thy sn nhp khc EU t c,
, Vi25].
y trong sn phm
  ki
thn phn gc t 
t l mc cao nh  (37%), Trung Qu
(5%) trong mt lon phm bao gt hp [25].
T n thy sn nhp khu t
Trung Quc nhim nitrofuran. Kt qu ln ph
thy, 22/89 mu (chim 22%) b t cm nitrofuran trong [11].
 . 

, 
,  2007 

 5 










SEM (3 


, 1 





1 



) 





ng 

0  3,55 ng/g. 2008 


1 










 12,6 ng/g;
2/754 







 









2  2,2 ng/g [1].
1.4. 



















 , :








 , 

 ( ), 
/MS.


U

2.ng, mu
ng, mu
t chuya nitrofuran, bao gm: AOZ, AMOZ,


Vt lin phm thc phng bao gm th
gia cm.
M u 

ng thi 4
cht chuyc phng bng
 sng khi ph LC/MS/MS. :
-  ng thi 4 cht chuya nitrofuran trong thc
phng bng LC-MS/MS.
- ng d t chuya nitrofuran trong thc phm
ng , , , gan.
2.1.2. Nu

 Khm:
 u kin v,
 u kit 

.
 Th
 Gii hn LOD, gii hng LOQ,
 Khong tuy
  ch lp li),
   thu h chch).
2.1.2.2. ng d
              
nitrofuran c th cht chuyc ph


i.

2.2. u
2.2.1. ng khi ph
 u
 
2.2.3. Thnh 


  liu
ng c u
2.3.1. Dng c t b
2.3.1.1. Thit b
- H thng s  ng khi ph khi ph LC/MS/MS bao gm: HPLC 20 AXL ca
i ph ABI 5500 QQQ ca Aplied Biosystem: b ph
lo phu nhit.
- Ct s
18
.
- Ct chit pha rn SPE (Oasis HLB).
- c vortex VELP.
- ng nht mu.
- 
-  
-  c 0,01g).
- 
2
u nhit.
- B u nhit
2.3.1.2 Dng c
- C 
- 

- Pipetman, pipet nha, pipet pasteur 2
- 
- Vial loi 1,8 ml.
- nh mc lo
- ng nghim th
t cht chun
t s du thuc loi tinh khi
2.3.2.1 Cht chun
- AOZ 10 mg/l (Dr.EhrenstorferGmbH) tinh khit 99%
- AMOZ 10 mg/l (Dr.EhrenstorferGmbH) tinh khit 99%
- AHD.HCl (Dr.EhrenstorferGmbH) tinh khit 99%
- SEM.HCl (Dr.EhrenstorferGmbH) tinh khit 99,5%
- d
4
-AOZ (Dr.EhrenstorferGmbH) tinh khit 99%
- d
5
-AMOZ (Dr.EhrenstorferGmbH) tinh khit 99%
- d
2
-AHD.HCl 10 mg/l (USA) tinh khit 99%
-
13
C
15
N
2
-SEM.HCl 10 mg/l (USA) tinh khit 98%
t
- Methanol (Merck ho tinh khit 99,9%)

- Amoni acetate (Merck ho tinh khit 98%)
- 2-NBA (Merck ho tinh khit 99%)
- K
2
HPO
4
.3H
2
O (Merck ho tinh khit 99%)
- NaOH (Merck ho tinh khit 99,9%)
- HCl 37% (Merck ho tinh khit 99,9%)
- nh mnh mn vch bc
ct.
- 2--nh mng methanol.
Dung dch chun b h
- K
2
HPO
4

2
HPO
4
.3H
2
nh mng
c ct 2 ln.
- nh mnh mc 1000 ml bc ct
2 ln.
- CH

3
COONH
4

3
COONH
4
nh mnh mc
1000 ml bc ct 2 ln.
2.3.3 Pha ch cht chun
- Chunh mc bng
nh mc 10 ml. Bo qun  - 20
0







- Chunh mc b
nh mc 10 ml. Bo qun  - 20
0








- Chunh mc bng
nh mc 10 ml.
- Chun SEM 1000 nh mc b
nh mc 10 ml. Bo qun  - 20
0







- Hn hp chun 4 cht 1 ml chun AOZ 10
nh mc bng methanol vnh
mc 10 ml. Bo qun  - 20
0







- Hn hp chun 4 chn hp chun 4
chnh mc bnh mc 10 ml. Bo
qun  - 20
0








- d
4
-
4
-nh mc bnh
mc 10 ml. Bo qun  - 20
0







- d
4
-
4
-nh mc bnh mc
10 ml. Bo qun  - 20
0








- d
5
-
5
-nh mc b
nh mc 10 ml. Bo qun  - 20
0







- d
5
-
5
-nh mc bnh
mc 10 ml. Bo qun  - 20
0








- Hn hp ni chun (d
4
-AOZ, d
5
-AMOZ, d
2
-AHD.HCl,
13
C
15
N
2
-n
t 1 ml chun d
4
-AOZ 10 mg/l, d
5
-AMOZ 10 mg/l, d
2
-   
13
C
15
N
2
-
SEM.nh mc bnh mc 10 ml. Bo qun  - 20
0





- Hn hp ni chun (d
4
-AOZ, d
5
-AMOZ, d
2
-AHD.HCl,
13
C
15
N
2
-n
n hp ni chun (d
4
-AOZ, d
5
-AMOZ, d
2
-AHD.HCl,
13
C
15
N
2
-SEM.HCl) 1 mg/l
nh mc 10 ml. Bo qun  - 20
0










T QU O LUN

3.1. Khu king LC/MS/MS
        d      t
chuyt chuy  
thu ph nn cao, hiu qu c hiu cho s nh (ch
yc, NH
3
, CO
2
 nhn MS i thy s dng 2-
 dn xut chuy  p cht


 (NPAOZ, NPAMOZ, NPAHD, NPSEM) vi nhin li.
3.1.1. Khu kin  ph 


3.1.1.1. Khion m
 nh 
cc. Qua tham kho mt s u [12, 13, 14, 16, 17, 18, 19, 21, 22, 23, 26]n

nh NPAOZ, NPAMOZ, NPAHD, NPSEM bng k thu
n t ESI vi ch  b tu kin khi ph
  ng chu   c dn xut bng 2-
 khn ch  kh i
vi tng cht, tng ion mu kin chy ngu bng 3.1.
Bảng 3.1: Điều kiện chạy nguồn ion hóa ESI

(CUR)
20 psi
m (CAD)
8 psi
Th  (IS)
5000 V
Nhi mao qun (TEM)
400
0
C
u phun (GS1)
50 psi
t ca lu
40 psi
Trong k thun t vi ch  b 
dng (MH)
+


= (M+1) 




:
M
0
+ H
+

+

Ti , kt qu c ch ra  bng 3.2
Bảng 3.2: Kết quả bắn phá các ion mẹ
Chuy
Kh M
Ion m (M+H)
NPAOZ
235
236
NPAMOZ
334
335
NPSC
208
209
NPAHD
248
249
d
4
-AOZ
239
240

d
5
-AMOZ
339
340
13
C-
15
N
2
SEM.HCl
211
212
D
2
-AHD.HCl
250
251
3.1.1.2. Khu kin b





ion con
Detector s d

 i ph 2 l 
chc la chc ion con t quan trng. Ion con phu g
nht 10 ln so vi ion m c mu cao cn phi chc mc

ng bng chuc dn xu
detector khi ph a chn 2 

  u cao nh 
ng. M ln nh ng, mnh ion con
th  th n chi vt ni chun, la
chn 1 ion c cao nht. Kt qu c  bng 3.3
Bảng 3.3: Năng lượng bắn phá và các ion con của các chất chuyển hóa nitrofuran
Chuy

nitrofuran
Ion m
(M+H)
+

Ion con
DP (V)
CE (eV)
CXP (V)
NPAOZ
236
134
80
15
10
104
80
27
14
NPAMOZ

335
291
80
15
16
262
80
21
16
NPSEM
209
192
80
11
18
166
80
13
14
NPAHD
249
134
80
15
18
104
80
27
14
d

4
-AOZ
240
134
80
17
16
d
5
-AMOZ
340
296
80
15
16
13
C-
15
N
2

SEM.HCl
212
168
80
13
12
d
2
-AHD.HCl

251
134
80
15
14




:
Theo qui 



2002/657/EC, 





(IP) 











LC/MS/M, 



 1 



 2 ion con, 





 (IP)  4. 















 [4]. 
, .










3.1.2. La chn c
 ng thi theo khuy
sn xut thit b khi ph  ng s di thit b 
cn 1%, amoni
acetate (0 ts da chn ct
o C18 









:
- Ct C18 :
- 


150mm,
- 2,1mm,
- 




3.1.3. Kh 


 cn gi dng ch  ra
gipt s 
ra gii gradient. Qua tham kho mt s  dng
 u kin s
- C
- 
- T 
- Mn h

, n: 20 ng/ml.






:
a) 


Gradient 1, 



3.1 :
Th
0,01
12,00
14,00
15,00
20,00
% MeOH
20
90
90
20
20


3.1: 









1 20 ng/ml

b) 

nh Gradient 2, 



3.2:
Th
0,01
5
8
9
12
% MeOH
20
90
90
20
20


3.2: 










2 20 ng/ml
c) 

3, 



3.3 :
Th
0,01
8
10
13
13,01
% MeOH
20
90
90
20
20


 3.3: 










3 20 ng/
d) 

4, 



3.4:
Th
0,01
10
12
15
15,01
% MeOH
20
90
90
20
20


 3.4: 










4 20 ng/ml
e) 

5, 



3.5:


Th
0,01
12,00
13,00
13,01
16,00
% MeOH
20
90
90
20
20


 3.5: 










5 20 ng/ml
 :
-  MeOH trong khong thi gian ngn (

 1, gradient 2,
a AOZ rt xu  ch . 














 , 












 -NH
2
 -
NH
3
+
. 

, 









 , 








3
COONH
4
-NH
3
+
.
- 













 a
chu tip theo.

3.1.4. Kht mu
Qua tham kho mt s u [12, 13, 14, 16, 17, 18, 19, 21, 22, 23, 26] t s
c ng d m : quy
 u bng chit lng  l u bng chit pha rn. Do 
t mu 







.
3.1.4.1. La ch u bng chit lng  lng
D ki 




-NBA 10mg/ml



n hp ni chun i ng



ch chuu



y ng, l  u nhit 40
0
C



ng 10 ml K
2
HPO
4
 NaOH 2M, lc 



 4500 rpm trong 15 







Chit lp 2 ln mi ln by lng N
2




tan cn bng 1 ml H

2
O:MeOH (60:40)



Chuyn m LC/MS/MS

3.1.4.2. La ch u bng chit pha rn




:





-NBA 10mg/ml



l hn hp ni chun i ng



ch chuu



y ng, l  u nhit 40
0
C



u bng 10 ml K
2
HPO
4
 NaOH 2M, l



 4500 rpm trong 15 







Ho
2
O



Np mt, ra  bng 2 x 2,5 ml H
2

O



 t SPE



Ra gii 



bng nghim



Thng N
2




tan cn bng 1 ml H
2
O:MeOH (60:40)



Chuyn m LC/MS/MS







2 

, 





2 


3.6:
Bảng 3.6: So sa
́
nh đô
̣
thu hồi của 2 quy trình chiết:
Tht ln
Chit SPE
Chit lng-lng
H (%)
H (%)
AOZ 20 ng/g
87,7
42,1

AMOZ 20 ng/g
92,7
45,0
AHD 20 ng/g
73,3
33,7
SEM 20 ng/g
70,5
30,6





:  thu h
vt lng lnh c
u tip theo
3.2. 






3.2.1 

















 2 , 






/z, 







 . 










 1 



2 ion


4 

, 

 




















3.2.1. Khng chun
3.2.1.1. Đường chuẩn của các chất nhóm nitrofuran sử dụng nội chuẩn (để phân tích mẫu
thực)
Bảng 3.7: Phương trình hồi quy 4 nitrofuran sử dụng nội chuẩn
TT
Cht
i qui
H s R
1
AOZ

0,9992
2
AMOZ

0,9995
3
AHD

0,9995
4
SEM
y 

0,9984

Nhận xét: t l dii chun (IS) trong khong 0,5  5 ng/ml
 h s 
2
> 0,99.
3.2.1.2. Đường chuẩn của các chất nhóm nitrofuran không sử dụng nội chuẩn (để đánh giá
hiệu suất thu hồi)
Bảng 3.8: Phương trình hồi quy của 4 nitrofuran không sử dụng nội chuẩn
TT
Cht
i qui
H s R
1
AOZ

0,9994
2
AMOZ

0,9989
3
AHD

0,9993
4
SEM

0,9993
Nhận xét: Dii n trong khong 0,5   s 

R
2
> 0,99.
3.2.2. Gii hi hng ca ph












 0,100  0,378
ng/g; 

0,300  1,13 ng/







2002/657/





. .
3. lp l thu hi
Thc hiu tht la nitrofuran  c n
i vi mi chng/g; 1,5 ng/g; 2 ng/g. p li 6
ln mi mu.
: 



 80,5  106%, 





(%RSD <
13,7%) 





 2002/657/EC. 



























4 

.
3.3. 









 ng d 
mt s loi thc pht qu  bng 3.16
Bảng 3.16: Kết quả phân tích mẫu thực theo phương pha
́
p thêm chuâ
̉
n

STT
Mu
Nitrofuran



thy (ng)
R%
1
Tht ln ch
Nguyn Cao
AOZ
0
KPH
-
1
0,87
87
AMOZ

0
KPH
-
1
0,96
96
AHD
0
KPH
-
1
0,78
78
SEM
0
KPH
-
1
0,72
72
2
Th Nguyn
Cao
AOZ
0
KPH
-
1
1,12
112

AMOZ
0
KPH
-
1
1,02
102
AHD
0
KPH
-
1
0,95
95
SEM
0
KPH
-
1
0,89
89
3
Th Mai
ng
AOZ
0
KPH
-
1
0,99

99
AMOZ
0
KPH
-
1
1,05
105
AHD
0
KPH
-
1
1,03
103
SEM
0
KPH
-
1
1,09
109
4
Gan ch ng
AOZ
0
KPH
-
1
0,88

88
AMOZ
0
KPH
-
1
0,97
97
AHD
0
KPH
-
1
0,75
75
SEM
0
KPH
-
1
0,69
69
5
Tht ln ch Cu
Giy
AOZ
0
KPH

1

1,02
102
AMOZ
0
KPH

1
0,79
79
AHD
0
KPH

1
1,01
101
SEM
0
KPH

1
1,03
103
6
Th Cu
Giy
AOZ
0
KPH

1
0,92
92
AMOZ
0
KPH

1
0,88
88
AHD
0
KPH

1
0.79
79
SEM
0
KPH

1
1,06
106
7
Tht ln ch Ngc

AOZ
0
KPH

1
1,05
105
AMOZ
0
KPH

1
1,11
110
AHD
0
KPH

1
0,98
98
SEM
0
KPH

1
0,67
67
8
Th Ngc

AOZ
0

KPH

1
0,76
76
AMOZ
0
KPH

1
0,82
82
AHD
0
KPH

1
0,97
97
SEM
0
KPH

1
0,73
73
KPH: không phát hiện < LOD của phương pháp,
R %: Phần trăm độ thu hồi.
:
Qua t s mu thn mu


 67  112% 










2002/657/EC. 







 























.
n c 
Trong bn luu kin ch  
ng LC/MS/MS trong mt s mu thc phng
(, ,  c m rng
dng nn mu sinh hc, mu sy rt c
nhu ti n 













thc tin.


KT LUN

 u kin thc nghim, vi mng d



c
ng khi ph  u
thc phng, 

t qu sau:
1.     u kin chy s  ng khi ph  nh 4 cht
chuym:
- Khu ki (th ng va chm
(CE) )  a tng cht nitrofuran.
- Kh

u kin sng: ct sc 
 n



metanol;
a gii gradient.
2. u kii nn mu tht ln

bng chit pha rn vi ct chit oasis HLB.
3.  cm:
- Khong tuyng t 0,5  i h s 
2

> 0,996.
- Gii h
      u v  nh  




nitrofuran.
-  thu h



80,5  106% cho th  tt.
-  lch chui thp (RSD% < 13,7%) cho th lp li
.
4. ng d u thc phm t 
i, cho th ng d 




nitrofuran trong thc phng.

References
Ting Vit
1. 

 (2009), Sư
̉
du
̣
ng kha
́
ng sinh trong chăn nuôi thu
́
y ơ
̉
Viê
̣
t Nam , 
y.
2. Trn T Hiu, T Vng Nghi, Nguyn V   Hóa học
phân tích, phần 2: Các phương pháp phân tích công cụ, t bn Khoa h thut,
i.
3. Nguyc Hu (2005), Các phương pháp phân tích Hữu cơ, t bi hc Quc
i.
4. Phm Lun (2000), Cơ sở lý thuyết sắc ký lỏng hiệu năng cao(HPLC),t bi
hc Qui.
5. NguyGiáo trình Các phương pháp tách, i
hc Khoa hc T i hc Qui.
6. T Th Tho (2010), Giáo trình Thống kê trong Hóa học phân tích, ng
i hc Khoa hc T i hc Qui.
7 Tho (2003), Thuốc kháng sinh và nguyên tắc sử dụng trong chăn nuôi, t

bi.
8. NguyGiáo trình Các phương pháp tách, i hc
Khoa hc T i hc Qui.
9. S - vic cấm sản xuất, nhập khẩu, lưu
thông và sử dụng một số loại kháng sinh hóa chất trong sản xuất và kinh doanh thức ăn chăn
nuôi ca B 
10. 28 TCN 194:2004,Các chất chuyển hóa thuộc nhóm nitrofuran trong thủy sản và sản
phẩm thủy sản – Phương pháp định lượng bằng sắc ký lỏng khối phổ - khối phổ, B Thy
Sn.
11. Trang web (2008), http//vietbao.vn/Kinh-te/My-kiem-tra-thuy-san-nuoi-Trung-Quoc-
Viet-Nam-lo-ngai/55154852/93. Vi

Ting Anh
12. Alexander Leitner, Peter Zollner, Wolfgang Lindner (2001)  
metabolites of nitrofuran antibiotics in animal tissue by high-performance liquid
chromatographyJournal of Chromatography A, Volume 939,
pp. 49-58.
13. Caroline Douny, Joelle Widart, Edwin De Pauw, Frederic sivestre, Packtrick Kestemont,
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