Table 4.

Quantification of rHAs from three H1N1 influenza virus strains using rHA from A/Vietnam/1203/2004 as an internal standard

Influenza virus strain (H1N1)	Concentration of protein, fmol/μ
	Manufacturer’s specification	Type of analysis
		Label‐free MS (%CV)	BCA (%CV)
A/Solomon Islands/03/2006	100	96·1 (2·3)	89·3 (0·1)
A/New Caledonia/20/1999	100	106·0 (3·7)	88·9 (0·1)
A/Brisbane/59/2007	100	136·6 (15·8)	128·9 (0·2)

MS, mass spectrometry; rHA, recombinant hemagglutinins.

Data shown are representative of the results of three biological replicates, each of which was obtained from three technical replicates.