Affiliations 

  • 1 Lopukhin Federal Research and Clinical Center of Physical Chemical Medicine of Federal Medical Biological Agency, 1A Malaya Pirogovskaya Street, 119435 Moscow, Russia
  • 2 Research Institute for Systems Biology and Medicine (RISBM), Nauchniy Proezd 18, 117246 Moscow, Russia
  • 3 Institute of Spectroscopy RAS, 5 Fizicheskaya Street, Troitsk, 108840 Moscow, Russia
  • 4 Laboratory of Biological Electron Microscopy, Institute of Physics (IPHYS), BSP 419, Ecole Polytechnique Fédérale de Lausanne, and Department of Fundamental Biology, Faculty of Biology and Medicine, University of Lausanne, CH1015 Lausanne, Switzerland
Polymers (Basel), 2023 Jun 08;15(12).
PMID: 37376252 DOI: 10.3390/polym15122607

Abstract

We propose and demonstrate dendrimer-based coatings for a sensitive biochip surface that enhance the high-performance sorption of small molecules (i.e., biomolecules with low molecular weights) and the sensitivity of a label-free, real-time photonic crystal surface mode (PC SM) biosensor. Biomolecule sorption is detected by measuring changes in the parameters of optical modes on the surface of a photonic crystal (PC). We describe the step-by-step biochip fabrication process. Using oligonucleotides as small molecules and PC SM visualization in a microfluidic mode, we show that the PAMAM (poly-amidoamine)-modified chip's sorption efficiency is almost 14 times higher than that of the planar aminosilane layer and 5 times higher than the 3D epoxy-dextran matrix. The results obtained demonstrate a promising direction for further development of the dendrimer-based PC SM sensor method as an advanced label-free microfluidic tool for detecting biomolecule interactions. Current label-free methods for small biomolecule detection, such as surface plasmon resonance (SPR), have a detection limit down to pM. In this work, we achieved for a PC SM biosensor a Limit of Quantitation of up to 70 fM, which is comparable with the best label-using methods without their inherent disadvantages, such as changes in molecular activity caused by labeling.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.