described in the experimental part. At this temperature the secondary structure and the local tertiary structure of BSA does not
undergo an appreciable changes according to the data of circular dichroism, fluorescent spectroscopy, and differential scanning
microcalorimetry [36].
The intensity size distribution functions in water–gelatin
–BSA
TA
–systems at different BSA/gelatin weight ratio (q) are shown
in Fig. 3.
The gelatin sample was strongly polydisperse. The main peak
(about 50%) has the average radius 140 nm. A small parts of the
low molecular weight fractions with the average sizes 3.8 nm (27%)
and 9 nm (23%) correspondingly were also detected. The interaction of gelatin with BSA
TA
leads to formation of the large complex
particles. At q = 0.75 the average size of the particles was 356 nm
that is three times higher then those of the binary water–gelatin
and water–BSATA
systems (Fig. 3a). At a higher q values (q = 1.0)
the average size of the particles sharply reach the maximal values
1500 nm. It seems that at such composition of the system all BSA
TA
form interpolymer complex with gelatin. At q = 1.0 z – average zeta
potential of particles for the water–gelatin–BSATAsystem decreases
up to 3.8 mV but remains still positive (Fig. 3b). Such behavior of
gelatin in the presence of BSA
TA
is completely different from that of
the water–gelatin–native BSA system. Intermacromolecular interaction of gelatin with native BSA at a q values equal and higher 1.0
leads to collapse gelatin macromolecules and formation compact
(30 nm in radius) BSA–gelatin complexes [20]. This gives proof that