PYRETHROID ANALYSIS. MARKET FOCUSED - Environmental TECHNICAL ARTICLE

Transcription

1 MARKET CUSED - Environmental PYRETHRID AALYSIS Pyrethroids are potent insecticides widely used in agriculture, disease control and household products. early all domestic fly aerosols use pyrethroids as the active ingredient whether these are surface or airborne sprays. Pyrethroids act by interfering with the insect s nervous system and, in high concentrations, affect humans in a similar way. TECHICAL ARTICLE Synthetic pyrethroids are also known as endocrine disrupters. ther toxicological properties inude: liver damage when subjected to long term exposure, allergic reactions and asthmatic attacks. The USEPA has found that many of the pyrethroids may also be carcinogenic. or this reason, the levels of synthetic pyrethroids in foods and the environment are always under ose scrutiny. Analysis by GC can be complex because many of the pyrethroids can have up to 8 optical isomers thus more than one peak can represent the same pyrethroid. Therefore, overlapping of signals can be a problem (e.g. Cypermethrin with 3 chiral centers can have up to 8 optical isomers, which inude 4 diastereoisomers) (igure 3). These identification problems have been made a thing of the past with SGE s 5% phenyl BPX5, 35% phenyl BPX35, and 50% phenyl BPX50 columns. Each column gives superb separation of the various isomers of the 6 components (Table ) in less than 33 minutes, allowing a fast turnaround time of samples. With an upper temperature limit of 360 C on all three columns, high boiling point contaminants can be baked out without damaging the stationary phase. This ensures that contaminants won't interfere with subsequent analyses. The bleed profiles at 300 C are excellent and the exceptional peak shape of each pyrethroid indicates a high degree of inertness on all three columns. Table shows the structures of the various Pyrethroids analyzed Pyrethroid. atural Pyrethrums. Allenthrin 6. enprorathrin PYRETHRID STRUCTURES Compound Structure CH Pyrethroid 0. Cyfluthrin. Cypermethrin. lucythrinate 3. envalerate 4. Esfenvalerate 5. Tralomethrin 6. Deltamethrin Compound Structure r

2 BPX5 5% phenyl (equiv) igure shows the separation of 6 pyrethroids on BPX5. ote the superb bleed profile at 300 C. BPX5 gives excellent separation of the synthetic pyrethroids. eakdown in the injection port of the thermally labile pyrethroids to there parent compounds such tralomethrin (6) to deltamethrin (7) and esfenvalerate (4) to fenvalerate (5) are the only coelutions seen. BPX5 DB-5 DB-5MS DB-5.65 XTI-5 Rtx-5ms Ultra- HP-5 HP-5MS HP5-TA SPB-5 MD-5S CP-Sil 8CB Rtx-5Sil MS AT-5 CP-Sil 8CB M igure BPX5, 0.5µm film Sample: 00ppm in Dichloromethane 30m x 0.5 mm ID 0 C, min. Rate : 5 C/min to 50 C, Rate : C/min to 60 C Rate 3: 5 C/min to 30 C inal Temp: 30 C, 6 min. He,.5 psi Carrier Gas low: 0. ml/min. Constant low: n Average Linear Velocity: 35 cm/sec at 0 C Split Split Ratio: 50: Injection Volume: ml Injection Temperature: 50 C Autosampler: o 4 mm ID Single Taper Liner Liner Part umber: 007 Column Part umber: 0540 CMPETS. atural Pyrethrums. Allethrin 6. enpropathrin 0. Cyfluthrin. Cypermethrin. lucythrinate 3. envalerate 4. Esfenvalerate 5. Tralomethrin 6. Deltamethrin , C {

3 BPX35 35% phenyl (equiv) igure shows excellent separation of the 6 synthetic pyrethroids on BPX35. The bleed at 300 C is excellent and the signal to noise in full scan mode is 60: for 0ng on column. igure 3 shows a chromatogram of the synthetic pyrethroid cypermethrin. ote the 4 peaks seen here representing the 4 diastereoisomers of cypermethrin. The structure of cypermethrin shown here shows the 3 chiral centers (*) of cypermethrin. BPX35 DB-35 DB-35MS Rtx-35 Rtx-35ms HP-35 HP-35MS SPB-35 MD-35 AT-35 igure & igure 3 BPX35 0.5µm film 6 Pyrethroids: 0ppm in methanol 30m x 0.5mm ID 50 o C, min Rate : 30 o C/min to 00 o C Rate : 4 o C/min to 300 o C inal Temp: 300 o C for 5 min He, 6.5 psi Carrier Gas low: 0.mL/min Constant low: n Average Linear Velocity: 35cm/sec at 50 o C Spiltless Purge on Time: 0.5min Purge on (Split) Vent: 60mL/min Injection Volume: µl Injection temperature: 50 o C Autosample: o 4mm ID Double Taper Liner Liner Part umber: 008 Column part umber: igure 3 Cypermethrin 3,4 5 Refer to Table for Peak Identification ,6 300ºC

4 BPX50 50% phenyl (equiv) igure 4 show the separation of the synthetic pyrethroids as run on BPX50. ote the run time on this chromatogram is 6 minutes for complete elution of the 6 pyrethroids. This allows analytical laboratories to have higher sample throughput. BPX50 V-7 SP-50 DB-7 DB-7MS DB-7ht Rtx-50 SPB-50 HP-50+ HP-7 AT igure 4 BPX50 0.5µm film 6 Pyrethroids: 0ppm in methanol 30m x 0.5mm ID 50 o C, min Rate : 30 o C/min to 00 o C Rate : 4 o C/min to 300 o C inal Temp: 300 o C for 5 min He, 6.5psi Carrier Gas low: 0.mL/min Constant low: n Average Linear Velocity: 35cm/sec at 50 o C Splitless Purge n Time: 0.5min Purge on (Split) Vent: 60mL/min Injection Volume: µl Injection Temperature: 50 o C Autosampler: o 4mm ID Double Taper Liner Liner Part umber: 008 Column Part umber: CMPETS. atural Pyrethrums. Allethrin 6. enpropathrin 0. Cyfluthrin. Cypermethrin. lucythrinate 3. envalerate 4. Esfenvalerate 5. Tralomethrin 6. Deltamethrin 4,5 3 7,

5 RDERIG IRMATI ID(mm) Length ilm Thickness Temperature Limits Part o. (mm) (m) (µm) ( C) BPX to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 350/ to 350/ to 360/ to 360/ to 360/ to 350/ to 350/ to 360/ to 350/ BPX to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ BPX to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ to 360/ SolGel-ms to 370/ to 370/ to 370/ to 370/ SUMMARY: BPX5, BPX35 and BPX50 columns show unparalleled performance for the separation of synthetic pyrethroids. These columns can be conditioned at the end of each analysis to remove any high boiling point contaminants without any degradation to the stationary phase and give excellent signal-to-noise with very little on-column breakdown.bpx5, BPX35 and BPX50 are the columns of choice for all pyrethroid analyses. or information on SGE s complete range of GC accessories, please refer to our latest catalog, or contact your nearest SGE office or distributor. Publication o. TA-0076-C Rev: 0 05/0 SGE International Pty. Ltd. Tel: +6 (0) ax: +6 (0) support@sge.com SGE Incorporated (USA) Toll ree: ax: usa@sge.com SGE rance Sarl Tel: +33 (0) ax: +33 (0) france@sge.com SGE Deutschland GmbH Tel: +4 (0) ax: +4 (0) germany@sge.com SGE Japan Inc. Tel: +8 (45) 885 ax: +8 (45) japan@sge.com SGE Australia Pty. Ltd. Toll ree: ax: (03) sales@sge.com SGE Europe Ltd. (UK) Tel: +44 (0) ax: +44 (0) uk@sge.com SGE Italia Srl. Tel: ax: sge.italia@tin.it SGE China Service Centre Tel: +86 (0) ax: +86 (0) sge@bj.col.com.cn SGE India Tel: + (0) ax: + (0) sgeindia@bom4.vsnl.net.in