title: Basic physiochemical and rheological properties of detergent sclerosants.
abstract: OBJECTIVE
  To determine the basic physiochemical properties and rheological activity of detergent sclerosants.
  
  
  METHODS
  Sodium tetradecyl sulphate and polidocanol liquid and foam sclerosants were investigated in a range of concentrations (0.1-3%), liquid-plus-air fractions (1+2 to 1+8) and dilutions in water (stock solutions) or in normal saline. The embolic agent ethanol was investigated for comparison. Density was measured using a digital balance. Surface tension was measured by the Du Nuoy ring method and used to determine the critical micellar concentration. Viscosity was measured using a cone-plate rheometer for liquid and a modified parallel plate method for foam.
  
  
  RESULTS
  Liquid sclerosant density decreased as the sclerosant concentration increased while foam density decreased with the increasing air fraction. The critical micellar concentration of polidocanol was 0.002% in both normal saline and water while that of sodium tetradecyl sulphate was 0.075% in normal saline and 0.200% in water. Viscosity of liquid sodium tetradecyl sulphate was lower than that of polidocanol. Foam sclerosants were at least 10,000-fold more viscous than liquid sclerosants and ethanol. All agents demonstrated a Non-Newtonian shear-thinning behaviour with a fall in viscosity at lower shear rates (<10 s(-1)). Polidocanol (but not sodium tetradecyl sulphate) foam viscosity progressively increased with increasing sclerosant concentration and liquid-plus-air fractions.
  
  
  CONCLUSIONS
  Liquid and foam sclerosants and ethanol are Non-Newtonian shear thinning fluids. Foam sclerosants are significantly more viscous than liquid agents.
authors.affiliation: School of Aerospace, Mechanical & Mechatronic Engineering, University of Sydney, Sydney, Australia Dermatology, Phlebology and Fluid Mechanics Research Laboratory, St Vincent's Centre for Applied Medical Research, Sydney, Australia.
authors.forename: Kaichung
authors.initials: K
authors.lastname: Wong
authors.affiliation: School of Aerospace, Mechanical & Mechatronic Engineering, University of Sydney, Sydney, Australia Dermatology, Phlebology and Fluid Mechanics Research Laboratory, St Vincent's Centre for Applied Medical Research, Sydney, Australia.
authors.forename: Tony
authors.initials: T
authors.lastname: Chen
authors.affiliation: Dermatology, Phlebology and Fluid Mechanics Research Laboratory, St Vincent's Centre for Applied Medical Research, Sydney, Australia Faculty of Medicine, University of New South Wales, Sydney, Australia.
authors.forename: David E
authors.initials: DE
authors.lastname: Connor
authors.affiliation: School of Aerospace, Mechanical & Mechatronic Engineering, University of Sydney, Sydney, Australia.
authors.forename: Masud
authors.initials: M
authors.lastname: Behnia
authors.affiliation: School of Aerospace, Mechanical & Mechatronic Engineering, University of Sydney, Sydney, Australia Dermatology, Phlebology and Fluid Mechanics Research Laboratory, St Vincent's Centre for Applied Medical Research, Sydney, Australia Faculty of Medicine, University of New South Wales, Sydney, Australia kparsi@stvincents.com.au.
authors.forename: Kurosh
authors.initials: K
authors.lastname: Parsi
mesh_terms: D000388:Air; D003902:Detergents / Q000737:chemistry*; D008823:Micelles; D000077423:Polidocanol; D011092:Polyethylene Glycols / Q000737:chemistry*; D012212:Rheology; D012597:Sclerosing Solutions / Q000737:chemistry*; D012981:Sodium Tetradecyl Sulfate / Q000737:chemistry*; D013500:Surface Tension
chemical_list: D003902:Detergents; D008823:Micelles; D012597:Sclerosing Solutions; D000077423:Polidocanol; D011092:Polyethylene Glycols; D012981:Sodium Tetradecyl Sulfate
keywords: Sclerosants; critical micelle concentration; density; foam; polidocanol; sodium tetradecyl sulphate; surface tension; viscosity