Binding of protein nanoparticles to immobilized receptors

The interaction of nanoparticles manufactured from human serum albumin (HSA) with different types of receptor surfaces was studied. Four different immobilization techniques were used to chemically link the receptors to the detector surfaces, namely: (i) a surface coated by monoclonal antibodies by a single step immobilization technique using carbodiimide, (ii) a surface coated by the same technique but using polyclonal antibodies, (iii) a surface coated by monoclonal antibodies immobilized through the sugar groups of antibodies and (iv) a surface coated by polyclonal antibodies immobilized by the same technique as in (iii).The results showed that there was almost no difference in the affinity of HSA in the molecular form to all of these surfaces. However, the binding behaviour of nanoparticles made from the same protein was quite different as successful nanoparticle binding was only observed when the surfaces were produced using method (ii).