Insecticides analysis

1
Insecticides analysis

• Dr. N.K. Ponkshe
• Head Quality
• Bayer CropScience

2
Insecticides

• Differentiation is generally based on Chemical
  family of the molecule
• Classical , Newer types
• Poly halogenated
• Carbamates , dithiocarbamates
• Organophosphorus
• Pyrethroids
• Triazines
• Urea derivatives
• Newer types CNIs , Cycloprop esters , Azoles ,

3

• Analytical procedures depend on the type of
  molecules
• Ranging from
• Chemical method of estimation involving
  hydrolysis , or absorbing the gas evolved ,
  titrimetry etc .
• Instrumental methods based on the functional
  group present in the molecule .
• UV , IR , Colourimetry , etc
• GLC and HPLC

4

• As the molecule chemistry has advanced , so are
  the testing methods
• Newer formulation types where
• Potency has increased
• Dosages have reduced
• Loading of AI , depending upon the formulation
  type is changing
• Molecules with Newer chemistry demand
• -- highly sophisticated instrumentation
• ---special techniques and
• -- most importantly expertise

5

• Constraints
• Availability of analytical procedures non
  availability of BIS specs
• Necessary instrumentation
• Non availability of reagents of specific quality
  
• Solvent systems / gradients
• Ref grade standards
• Proper storage facility of ref grade standards
• Training

6
Result

• Constraints Methods based on instrumental
  analysis can lead to
• Inaccurate absorptions
• Improper resolution of the peaks
• Incorrect areas marked for peaks under
  consideration
• Non repeatability in successive measurement /
  injections Errors in areas
• All the above or even a single factor can lead to
  A wrong outcome

7
Corrective action

• Using ref grade standards from a reliable source
  Manufacturer
• Adopt correct instrumental conditions
• Due care must to be taken while storing ref
  standards
• Follow recommended analytical procedures ( use
  internal standards wherever recommended )
• Advantage of using internal standard Error
  gets minimized to a great extent
• Carry out analysis in duplicate
• Training / Validation of method / Demonstration

8

• Thanks !