title: Reaction of 2,6-dichloroquinone-4-chloroimide (Gibbs reagent) with permethrin - an optical sensor for rapid detection of permethrin in treated wood.
abstract: BACKGROUND
  A novel optical sensor for the rapid and direct determination of permethrin preservatives in treated wood was designed. The optical sensor was fabricated from the immobilisation of 2,6-dichloro-p-benzoquinone-4-chloroimide (Gibbs reagent) in nafion/sol-gel hybrid film and the mode of detection was based on absorption spectrophotometry. Physical entrapment was employed as a method of immobilisation.
  
  
  RESULTS
  The sensor gave a linear response range of permethrin between 2.56-383.00 μM with detection limit of 2.5 μM and demonstrated good repeatability with relative standard deviation (RSD) for 10 μM at 5.3%, 100 μM at 2.7%, and 200 μM at 1.8%. The response time of the sensor was 40 s with an optimum response at pH 11.
  
  
  CONCLUSIONS
  The sensor was useful for rapid screening of wood or treated wood products before detailed analysis using tedious procedure is performed. The validation study of the optical sensor against standard method HPLC successfully showed that the permethrin sensor tended to overestimate the permethrin concentration determined.
authors.affiliation: Forest Products Division, Forest Research Institute Malaysia, Selangor DE 52109, Malaysia.
authors.forename: Mohamad Nasir Mat
authors.initials: MN
authors.lastname: Arip
authors.affiliation: Faculty of Science and Technology/South East Asia Disaster Prevention Research Institute (SEADPRI), Universiti Kebangsaan Malaysia, Bangi, Selangor DE 43600, Malaysia.
authors.forename: Lee Yook
authors.initials: LY
authors.lastname: Heng
authors.affiliation: Faculty of Science and Technology, Universiti Sains Islam Malaysia (USIM), Nilai, Negeri Sembilan 71800, Malaysia.
authors.forename: Musa
authors.initials: M
authors.lastname: Ahmad
authors.affiliation: Faculty of Science and Technology/South East Asia Disaster Prevention Research Institute (SEADPRI), Universiti Kebangsaan Malaysia, Bangi, Selangor DE 43600, Malaysia.
authors.forename: Siti Aishah
authors.initials: SA
authors.lastname: Hasbullah
keywords: 2,6-dichloro-p-benzoquinone-4-chloroimide; Nafion; Optical sensors; Permethrin; Sol–gel