title: Assessment of pre-analytical and analytical variables affecting peptidome profiling of gingival crevicular fluid by MALDI-TOF mass spectrometry.
abstract: BACKGROUND
  Gingival crevicular fluid (GCF) may be a source of new biomarkers of periodontitis/gingivitis. However, the minute volumes of GCF harvested in healthy sites are a serious drawback. We evaluated how pre-analytical and analytical variables concerning GCF collection and processing, could significantly influence quality and reproducibility of MALDI-TOF profiles.
  
  
  METHODS
  GCF was collected from healthy sites. The use of paper strips vs paper points was compared. Peptides and proteins were extracted by centrifugal elution in different solutions, at different accelerations, with and without protease inhibitor cocktail (PIC). Finally, we evaluated how matrix composition and matrix/sample volume ratio affect the reproducibility of MALDI-TOF profiles.
  
  
  RESULTS
  Trifluoroacetic acid elution generated richer gingival fingerprints compared to acetic acid, independently of the collection device. Centrifugation speed and PIC supplementation did not change GCF profiles. A fine modulation of matrix composition and matrix/sample volume ratio resulted in a satisfactory reproducibility (CV less than 10% for peak area and signal-to-noise ratio).
  
  
  CONCLUSIONS
  An optimized procedure, enabling generation of reproducible MALDI-TOF profiles from limited volume of GCF, is proposed. These fingerprints may serve as reference for future studies oriented to the maintenance and preservation of good gingival status and to discovery biomarkers of periodontitis/gingivitis.
authors: Department of Health Sciences, University "Magna Græcia" Catanzaro, University Campus, Europa Avenue, 88100 Catanzaro, Italy.
authors: Mariaimmacolata
authors: M
authors: Preianò
authors: Department of Health Sciences, University "Magna Græcia" Catanzaro, University Campus, Europa Avenue, 88100 Catanzaro, Italy.
authors: Daniela
authors: D
authors: Falcone
authors: Department of Health Sciences, University "Magna Græcia" Catanzaro, University Campus, Europa Avenue, 88100 Catanzaro, Italy.
authors: Giuseppina
authors: G
authors: Maggisano
authors: Department of Medical and Surgical Sciences, University "Magna Græcia" Catanzaro, University Campus, Europa Avenue, 88100 Catanzaro, Italy.
authors: Tiziana
authors: T
authors: Montalcini
authors: Department of Drug Sciences and Products for Health, University of Messina, Viale Annunziata, 98168 Messina, Italy.
authors: Michele
authors: M
authors: Navarra
authors: Department of Health Sciences, University "Magna Græcia" Catanzaro, University Campus, Europa Avenue, 88100 Catanzaro, Italy.
authors: Sergio
authors: S
authors: Paduano
authors: Department of Health Sciences, University "Magna Græcia" Catanzaro, University Campus, Europa Avenue, 88100 Catanzaro, Italy.
authors: Rocco
authors: R
authors: Savino
authors: Department of Health Sciences, University "Magna Græcia" Catanzaro, University Campus, Europa Avenue, 88100 Catanzaro, Italy. Electronic address: terracciano@unicz.it.
authors: Rosa
authors: R
authors: Terracciano
mesh_terms: D015415:Biomarkers / Q000032:analysis / Q000737:chemistry; D005260:Female; D005883:Gingival Crevicular Fluid / Q000737:chemistry*; D005891:Gingivitis / Q000175:diagnosis; D006801:Humans; D008297:Male; D057786:Peptidomimetics / Q000032:analysis*; D010518:Periodontitis / Q000175:diagnosis; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D015415:Biomarkers; D057786:Peptidomimetics
keywords: Gingival crevicular fluid; MALDI-TOF; Peptidomics; Proteomics