title: Human saliva total protein levels by AV17 pigment based analysis: validation, stability and short-term variation studies.
abstract: BACKGROUND
  A colorimetric method based on acid violet pigment, namely AV17, to analyse salivary total protein content, was assessed.
  
  
  METHODS
  Human saliva sample or standard (50 microL) was added to 1.5 mL of AV17 working solution (1 mg/mL in 75 mmol/L sodium chloride and 1.7 mol/L phosphoric acid). Total protein concentration was measured at 546 nm. Salivary total protein of healthy subjects was analyzed.
  
  
  RESULTS
  The standard protein was Human Serum Albumin and the detection range was 38 mg/L - 900 mg/L with a LOD and LOQ of 26 mg/L and 64 mg/L, respectively. Intraday CVs were 3% - 5% and interday CVs were 3%-6%. The dilution test demonstrated a correlation coefficient of 0.999 and the recovery tests ranged from 108% to 111%. Saliva sample stability was also demonstrated. No intra-individual salivary total protein variation was found during the morning.
  
  
  CONCLUSIONS
  The method suitability for laboratory diagnostic purposes to analyse human saliva protein content and stability was demonstrated.
authors.affiliation: Clinical Biochemistry, Dept. of Medical Diagnostic and Spec. Ther. University of Padova, Italy.
authors.forename: Maddalena
authors.initials: M
authors.lastname: Prearo
authors.forename: Giorgia
authors.initials: G
authors.lastname: Antonelli
authors.forename: Rosalba
authors.initials: R
authors.lastname: Gatti
authors.forename: Paolo
authors.initials: P
authors.lastname: Spinella
authors.forename: Elio F
authors.initials: EF
authors.lastname: De Palo
mesh_terms: D003124:Colorimetry / Q000379:methods*; D006801:Humans; D057230:Limit of Detection; D010860:Pigments, Biological; D012471:Salivary Proteins and Peptides / Q000378:metabolism*
chemical_list: D010860:Pigments, Biological; D012471:Salivary Proteins and Peptides