Selective amplifications were performed subsequently on a 1 : 20 dilution of the pre-amplified fragments.
The homogeneous suspension was used for the enzyme assay and the dilution factor was taken into account for calculations.
Sera were tested at 1 in 200 dilution on antigen coated plates.
The test was repeated at least 3 times for each dilution (1/2 and 1/5) of immune serum.
Titres were defined as log10 of the dilution that resulted in an absorbance of 0.5, obtained by graphic interpolation.
Repulsion can be dealt with by dilution, increasing ionic strength, and/or extrapolating the data to infinite dilution.
Suspensions of lower spore concentrations were prepared by threefold dilutions.
Thus, these curves can be used to extrapolate the scattering to infinite dilution.