Other Pesticides

Paraquat and diquat were analyzed using Asahipak ES-502C 7C (a column for weak cation exchange chromatography).

Sample :
Paraquat
Diquat

Column       : Shodex Asahipak ES-502C 7C (7.5mmID*100mm)
Eluent       : 50mM Sodium phosphate buffer(pH7.0) + 150mM NaCl 
Flow rate    : 1.0mL/min
Detector     : UV(288nm)
Column temp. : 30deg-C

Paraquat in rat serum was analyzed using Asahipak GS-320 7G (a multimode column).
GS-320 7G is an old type of GS-320 HQ.

Sample : Rat Serum
Paraquat

Column       : Shodex Asahipak GS-320 7G (7.5mmID*500mm)
Eluent       : 50mM Phosphate buffer(pH7.2)/CH3OH=80/20 + 0.2M NaCl
Flow rate    : 1.0mL/min
Detector     : UV(254nm)
Column temp. : 40deg-C

Courtesy of Dr.Chiba, Nihon University

Glyphosate and glufosinate which are phosphorus-containing amino acid type herbicides were analyzed with IC/ICP-MS using IC SI-90 4E (a column for anion chromatography).

Sample : 20micro-L
1. Glufosinate
2. Glyphosate

Column       : Shodex IC SI-90 4E (4.0mmID*250mm)
Eluent       : (A) 0.3mM NaOH aq.
               (B) 0.3mM NaOH + 20mM Na2CO3 aq.
                Gradient:
                 0 to 20min, A/B=95/5 
                20 to 30min, A/B=95/5 to 50/50
                30 to 40min, A/B=50/50
Flow rate    : 1.0mL/min
Suppresor    : Dionex AMMS-ICS II
Detector     : ICP/MS, P at m/z=31
Column temp. : Room temp.

Glyphosate which is phosphorus-containing amino acid type herbicide was analyzed with IC/ICP-MS using IC SI-90 4C (a column for anion chromatography). Since SI-90 4C column has length as short as 100mm, it can perform rapid analysis of glyphosate. In this experiment, after adding glyphosate into serum, it pretreated by centrifugal type extra filtration, and analyzed. as for a recovery rate, about 100% is obtained in the range of 0.1 to 100 ng/micro- L — detection marginal concentration was 0.1ng/micro-L.
Shodex IC SI-90 4C is a special order.

Sample :
1. Glyphosate

Column       : Shodex IC SI-90 4C (4.6mmID*100mm)
Eluent       : (A) H2O
               (B) 13mM Na2CO3 + 20mM NaHCO3 aq.
               Gradient: 
               0 to  3min, A/B=90/10
               3 to 15min, A/B=90/10 to 70/30
Flow rate    : 1.0mL/min
Suppresor    : Dionex AMMS-ICS II
Detector     : ICP/MS, P at m/z=31
Column temp. : Room temp.

Neonicothinoids, one category of insecticides, were analyzed using RSpak DE-413.

Sample : Neonicotinoids 1.25micro-g/mL,
10micro-L
1. Dinotefuran
2. Nitenpyram
3. Thiamethoxiam
4. Clothianidin
5. Acetamiprid
6. Imidacloprid
7. Thiacloprid

Column       : Shodex RSpak DE-413 (4.6mmID*150mm)
Eluent       : 10mM Formic acid aq./CH3CN=80/20
Flow rate    : 0.8mL/min
Detector     : Shodex RI
Column temp. : 40℃deg-C

Ethoxyquin is commonly used to prevent color loss of apples and pear. It is also used to prevent raincidification of fats in animal base lipids and in fish powder utilized for animal food products. Ethoxyquin is generally analyzed by ODS columns. However, 2nd amin in ethoxyquin suffer from ionic adsorption with residual silanol, which results in poor repeatability of the analysis. In contrast, polymer-based reversed phase column, Asahioak ODP-50 4E, does not have residual silanol, thus it will not be affected by the adsorption problem and provide good repeatability.

Sample : Ethoxyquin 0.1micro-g/mL, 20micro-L

Column       : Shodex Asahipak ODP-50 4E (4.6mmID*250mm)
Eluent       : OSD(A),(B),(C) (4.6mmID*250mm each)
               Acetonitorile-Water (4:1) containing 50mg/L of BTH
Flow rate    : 1.0mL/min
Detector     : Fluorescence (Ex. 370nm, Em. 415nm)
Column temp. : 40℃deg-C

Courtesy of Mr. Hisaaki Hiraoka, Food and Agricultural Materials Inspection Center, Japan