The first step of bacterial or viral invasion is affinity and presumably multisite binding of bioparticles to an elasticmatrix like a living tissue. We have demonstrated that model bioparticles such as inclusion
bodies (spheres of a
bout1
![](/images/entities/mgr.gif)
m in size)
Escherichia coli cells (rods 1 × 3
![](/images/entities/mgr.gif)
m), yeast cells (8
![](/images/entities/mgr.gif)
m spheres), and synthetic microgel particles(0.4
![](/images/entities/mgr.gif)
m spheres) are binding via different affinity interactions (IgG anti
body-protein A, sugar-lectin, and metalion-chelate) to a macroporous hydrogel (MH) matrix bearing appropriate ligands. The elastic deformation of the MHresults in the detachment of affinity
bound bioparticles. The particle detachment on elastic deformation is believedto be due to multipoint attachment of the particles to affinity matrix and the disturbance of the distance between affinityligands when the matrix is deformed. No release of affinity
bound protein occurred on elastic deformation. Theefficiency of the particle release by the elastic deformation depends on the density of the ligands at the particle surfaceas well as on the elasticity of the matrix for relatively large particles. The release of the particles occurred irrespectivelyof whether the deformation was caused by external forces (mechanical deformation) or internal forces (the shrinkageof thermosensitive macroporous poly-
N-isopropylacrylamide hydrogel on increase in temperature).