Page 38 - Application Handbook - Liquid Chromatography

32

 Analysis of Melamine and Its Related Substances in Fertilizers

Fig. 3 shows the sample preparation process
i
t
t
l
l
i
er
f
e (
e (
er
f
50 g
)
)
er
0.

er
i
50 g
i
z
z
0.
am
pl
pl
am
Sample (fertilizer) 0.50 g described in the fertilizer test method.
S S
Fertilizer certified reference materials A and
et
n
v/
i
it
(
W
hy
/
Acetonitrile / Water / Diethylamine = 5/4/1 (v/v/v)v) B* were treated in accordance with the
at
c
e
er
t
D
A
o
/
ne
=
i
l
am
1
v/
ile
4/

5/
r
100 mL sample preparation procedure described in
100 mL
Fig. 3. The final solutions from the sample
Sonicate
S oni c at e preparation were then spiked with melamine,
(30 minutes) ammeline, and ammelide with the standard
(30 minutes)
addition technique so that the respective
C ent r i f uge concentrations of these substances reached
Centrifuge
(2000×g 5 minutes)
(2000×g 5 minutes) 10 mg/L. Figures 4 & 5 show the
chromatograms obtained. The analysis
conditions are the same as in Table 1. (In
accordance with the sample preparation
procedure in Fig. 3, if 100 % of the melamine
Low
l
er
er
ay
l
ay
er
Upper layer Lower layer and related substances were recovered, the
U
pper
5mL content of these substances would be
calculated as equivalent to a 2 % mass
i
w
t
L
h
i
l
Dilute to 50 mL with fraction with respect to the fertilizer.)
D
ut
t
e
o 50 m
Mobile phase
Mobile phase
F ilt r a t e *Fertilizer certified reference material A
Filtrate
(FAMIC-A-10) is a high-analysis compound
fertilizer containing urea. Fertilizer certified
reference material B (FAMIC-B-10) is a
t
I
t
ec
nj
P
LC
o H
Inject to HPLC general-compound fertilizer not containing
urea. Both are commercially available from
FAMIC.
Fig. 3: Sample Preparation

mAU mAU
150  Peaks 150  Peaks
Fertilizer Certified 2 Fertilizer Certified 2
Reference Material A 1. Ammelide Reference Material B 1. Ammelide
125 2. Melamine 125 2. Melamine
3. Ammeline 3. Ammeline
100 100
75 3 75 3
1 1
50 50
25 25
0 0
0.0 2.5 5.0 7.5 10.0 12.5 min 0.0 2.5 5.0 7.5 10.0 12.5 min
Fig. 4: Chromatogram of Fertilizer Certified Reference Fig. 5: Chromatogram of Fertilizer Certified Reference
Material A (spiked with 10 mg/L melamine, ammeline Material B (spiked with 10 mg/L melamine, ammeline
and ammelide) and ammelide)
First Edition: April 2013
© Shimadzu Corporation, 2013