We want to synthesize a gold nanoparticle (GNP) conjugate with both antibodies and DNA nucleotides. We synthesize GNP conjugate with antibodies, and we always use a detergent buffer with BSA. In the case of adding DNA to the synthesis, a colleague recommended not to use a detergent buffer as it might interfere with the DNA, so taking the advice I followed Nam, Thaxton and Mirkin’s (2003) protocol, in which they dispersed the final GNP-AB-DNA conjugate in a 0.1 M NaCl/0.01 M PBS. However, after doing this, the conjugate started to aggregate and I can tell that it is not stabilizing our conjugate. Any ideas?