Surfactant protein B amount and kinetics in newborn infants: An optimized procedure

Manuela Simonato, Aldo Baritussio, Luca Vedovelli, Giulia Lamonica, Virgilio Paolo Carnielli, Paola Elisa Cogo

Research output: Contribution to journalArticlepeer-review


Surfactant protein B (SP-B) plays a key role in surfactant homeostasis affecting its biophysical properties and physiological function. Recently, a method to measure SP-B amount and kinetics from tracheal aspirates (TAs) became available. The main objective of this study was to improve the critical steps of the procedure to obtain a better SP-B sensitivity. We administered a 24 h continuous infusion of 1 mg/kg/h of 113 C-leucine to ten newborn infants. SP-B was isolated from serial TAs and its fractional synthesis rate, secretion time, peak time and half life were derived from 13 C enrichment curves obtained by gas chromatography mass spectrometry. SP-B amount in TAs was also assessed. During the extraction step, acidification and organic solvent ratio optimization doubled the recovery of SP-B from TAs, so did the elongation of the propylation time (from 20 min to 1 h) with enhanced leucine derivatization yield. Measurement of 13 C leucine enrichments, and therefore all SP-B kinetics parameters, were successfully calculated in all TAs samples due to the increase of SP-B yield. SP-B amount was 0.29 (0.16-0.41) % of total phospholipids with a minimum value of 0.08% belonging to one of the respiratory distress syndrome (RDS) patients. In conclusion, this new procedure enables accurate determination of SP-B kinetics even in the presence of low protein amount like in preterm RDS patients.

Original languageEnglish
Pages (from-to)1415-1419
Number of pages5
JournalJournal of Mass Spectrometry
Issue number11
Publication statusPublished - Nov 2012


  • isotope
  • mass spectrometry
  • surfactant protein B

ASJC Scopus subject areas

  • Spectroscopy


Dive into the research topics of 'Surfactant protein B amount and kinetics in newborn infants: An optimized procedure'. Together they form a unique fingerprint.

Cite this