RESEARCH ARTICLE Combinatorial screening of polymer nanoparticles for their ability to recognize epitopes of AAV-neutralizing antibodies Elena V. Piletska 1 | Eugeny Mirkes 2 | Stanislav S. Piletsky 3 | Hasan Abosoglu 1 | Alfeshani Cassim 1 | Edmund Chu 1 | Simon Doughty 1 | Shaun-Jones Eganda 1 | Hikari Fuchigami 1 | Aleah Hussein 1 | Meedhu Olickal 1 | Neelay Parmar 1 | Akhil Sebastian 1 | Sergey A. Piletsky 1 1 School of Chemistry, University of Leicester, Leicester, UK 2 School of Mathematics, University of Leicester, Leicester, UK 3 Department of Chemistry, Imperial College, London, UK Correspondence Elena V. Piletska, School of Chemistry, University of Leicester, University Road, Leicester LE1 7RH, UK. Email: ep219@le.ac.uk Funding information European Union's H2020 research and innovation program, Grant/Award Number: 755225 Abstract A library of 17 nanoparticles made of acrylate and methacrylate copolymers is pre- pared, characterized, and screened against six epitopes of adeno-associated viruses (AAV)-neutralizing antibodies to assess their affinity and specificity. Peptide epitopes are immobilized onto the surface of glass beads, packed in filtration microplates, and incubated with fluorescein-labelled nanoparticles. Following intense washing, the affinity of nanoparticles to immobilized epitopes is assessed by measuring the fluores- cence of captured nanoparticles. The results show that polar monomers, acrylic acid in particular, have a positive impact on polymer affinity towards all peptides used in this study. The presence of hydrophobic monomers, on other hand, has a negative impact on polymer binding. The composition of peptides used in this study has no noticeable impact on the affinity of synthesized nanoparticles. The affinity of nanoparticles with the highest affinity to peptide targets does not exceed millimolar level. Overall, it is found that the synthesized library showed modest affinity but lacked specificity, which should be further “tuned,” for example, by using molecular imprinting to achieve an acceptable level of affinity and specificity for practical application. KEYWORDS affinity, antibodies, epitopes, molecular imprinting, nanoparticles 1 | INTRODUCTION The main objective for the work presented here is the development of a tool for improving the efficiency of gene therapy used in the treatment of Crigler-Najjar (CN) syndrome. CN syndrome is a genetic disorder caused by an inability or diminished ability to convert and clear bilirubin from the body. The inability to convert bilirubin from its unconjugated to its conjugated form is due to a genetic mutation of the enzyme uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1), which is responsible for the conversion. The unconjugated form, which is not readily water-soluble, accumulates in the body and leads to abnormally high levels of the unconjugated form. This toxic substance then builds up in the body, causing unconjugated hyper- bilirubinemia and jaundice. This poses threats to the health of the indi- vidual and can cause devastating effects as once accumulated, the unconjugated form acts as a neurotoxic on the brain and CNS, causing symptoms such as muscle spasms, fatigue, and vomiting, as well as other sensory and physical ailments. 1 Mutations at one of the genes Received: 13 August 2019 Revised: 26 September 2019 Accepted: 21 October 2019 DOI: 10.1002/jmr.2824 J Mol Recognit. 2019;e2824. wileyonlinelibrary.com/journal/jmr © 2019 John Wiley & Sons, Ltd. 1 of 9 https://doi.org/10.1002/jmr.2824