Table 1.

Effect of polymers on surface activity of simple lipid mixtures (SLM) and complex lipid mixtures (CLM) containing 1% SP-B and 1% SP-C. (Abbreviations defined in Methods).

SLM
	No Polymer	HA	PEG	Dextran	HA/PEG	HA + dextran	Native surfactant (No Polymer)
Adsorption (mN/m)	22±0.4	22±0.6	20±0.2*	20±0.2*	21±0.2*	20.±0.2*	20±0.2
γmin (mN/m) 10th cycle	12±1	0±0*	8±1	2±0.5*	1±0.3*	0.4±0.2*	10±0.7
γmax (mN/m) 10th cycle	32±0.8	54±2*	27±0.6*	28±0.2*	38±1*	46±3*	30±0.7
γmin (mN/m) 5 min	9±2	0±0.1*	0.2±0.2*	0±0.1*	0±0.1*	0±0.1*	2 ±0.6*
γmax (mN/m) 5 min	31±0.5	48±2*	27±0.4*	27±0.2*	34±0.5*	43±2*	30±0.5
A10	41±3	2±0.5*	22±0.7*	19±0.6*	7±1*	3±0.7*	23±2*

CLM
	No Polymer	HA	PEG	Dextran	HA/PEG	HA/Dextran	Native surfactant (No Polymer)
Adsorption (mN/m)	21±0.3	22±0.5	20±0.2	21±0.2	20±0.2	21±0.3	20±0.2*
γmin (mN/m) 10th cycle	14±0.9	7±1*	12.2±1	12±1.2	6±1*	5±1*	10±0.7
γmax (mN/m) 10th cycle	29±0.5	34±1*	28±0.1	29±0.8	33±1*	40±1*	30±0.7
γmin (mN/m) 5 min	5±1	0.8±0.8	5±1.3	3±0.8	1±0.5	1±0.8	2 ±0.6
γmax (mN/m) 5 min	30±0.6	35±0.6*	29±0.7	31±1.3	31±1.5	40±1*	30±0.5
A10	33±2.3	17±3*	33±2	29±1	10±0.2*	6±0.6*	23±2

Values are means ± SEM for five replicates. An asterisk indicates the value is significantly different from that for the mixture with no polymer (first column). P< 0.05 by ANOVA multiple comparison.