IBIMOL   23987
INSTITUTO DE BIOQUIMICA Y MEDICINA MOLECULAR PROFESOR ALBERTO BOVERIS
Unidad Ejecutora - UE
artículos
Título:
Determining the fluid ordered and disordered phases in a pulmonary surfactant by electron spin resonance technique.
Autor/es:
FACORRO GRACIELA; CIMATO ALEJANDRA; MARTÍNEZ SARRASAGUE MARGARITA
Revista:
RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Amsterdam; Año: 2020 vol. 271
ISSN:
1569-9048
Resumen:
Pulmonary surfactant (PS) main function is to reduce surface tension at alveolar interface. Two lipids domains coexist in surfactant membranes: a liquid-ordered (Lo) and a liquid-disordered (Ld) phases. This coexistence of phases would be crucial for the surfactant activity. Until now, the proportion of phases was determined qualitatively. We design an electronic spin resonance (ESR) technique to quantify the lipid fraction in Ld phase.Methods: PS with or without extra Cho was labeled with 5DE to estimate the membrane fluidity and with TEMPO to determine the PL in Ld phase.Results: TEMPO partition coefficient for this PS was (0.78±0.03). Cholesterol in PS not modified this coefficient. A unique equation was established for the calculation of PL in Ld phase with an error of less than 3%.The equation is valid for different batches of surfactant regardless of the cholesterol content. Conclusions: The proposed method is simple, precise and allows evaluating changes in PS lateral structure that could affect its biophysical properties. Keywords: pulmonary surfactant, lipid phases, ESR, TEMPO