title: Ultra low concentration deltamethrin loaded patch development and evaluation of its repellency against dengue vector Aedes (S) albopictus.
abstract: BACKGROUND
  Mosquito repellents and emanators confer protection against mosquito bites through spatial action of emanated vapours which are released into the adjoining environment. Synthetic insecticides released into the environment in ultra low volume vapour phase deter the mosquitoes from biting humans in a protected space.
  
  
  METHODS
  Formulation patches were prepared using the solvent evaporation method over a backing membrane and using Dibutylphthalate (DBT) as a plasticizer. The effect of formulation variables on the deltamethrin release from the patch matrices were studied under accelerated conditions, whereas, HPLC was used for quantitative estimation of deltamethrin. The prepared patch formulations were subjected to physicochemical studies, such as, deltamethrin content, thickness, weight variation, percent moisture content, moisture uptake, surface area and surface pH determination. Deltamethrin-polymer interaction and compatibility was ascertained using DSC and FT-IR, while surface morphology and deltamethrin distribution in the patch were studied using SEM technique. Repellent activity of the patch formulations was evaluated against Ae. albopictus mosquitoes.
  
  
  RESULTS
  Blends of polymeric combinations of polyvinylpyrrolidone (PVP) and ethyl-cellulose (EC) with admixture of deltamethrin provided prolonged repellent activity against Ae. albopictus mosquitoes. Physicochemical characterisation indicated the suitability of deltamethrin patch formulation with the polymeric combinations of PVP and EC. Patches were very effective against laboratory reared Ae. albopictus mosquitoes. No significant difference was observed between the performance of test patches and commercially available repellent cream Mosqshield®.
  
  
  CONCLUSIONS
  Deltamethrin loaded patches provided effective repellency against Ae. albopictus mosquitoes. The study emphasised that deltamethrin released to the environment in low concentration could be an excellent spatial repellent against hematophagous mosquitoes.
authors.forename: Pronobesh
authors.initials: P
authors.lastname: Chattopadhyay
authors.forename: Sunil
authors.initials: S
authors.lastname: Dhiman
authors.forename: Kangujam
authors.initials: K
authors.lastname: Devi
authors.forename: Subham
authors.initials: S
authors.lastname: Banerjee
authors.forename: Bipul
authors.initials: B
authors.lastname: Rabha
authors.forename: Ashwani
authors.initials: A
authors.lastname: Chaurasia
authors.forename: Vijay
authors.initials: V
authors.lastname: Veer
mesh_terms: D000330:Aedes / Q000187:drug effects*; D000818:Animals; D055598:Chemical Phenomena; D002626:Chemistry, Pharmaceutical; D002851:Chromatography, High Pressure Liquid; D003715:Dengue / Q000517:prevention & control; D004199:Disease Vectors; D005260:Female; D006801:Humans; D007299:Insect Bites and Stings / Q000517:prevention & control; D007302:Insect Repellents / Q000494:pharmacology*; D009570:Nitriles / Q000494:pharmacology*; D011722:Pyrethrins / Q000494:pharmacology*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D007302:Insect Repellents; D009570:Nitriles; D011722:Pyrethrins; C017180:decamethrin