• 文献标题:   Surface Engineering of Graphene through Heterobifunctional Supramolecular-Covalent Scaffolds for Rapid COVID-19 Biomarker Detection
  • 文献类型:   Article
  • 作  者:   PICCININI E, ALLEGRETTO JA, SCOTTO J, CANTILLO AL, FENOY GE, MARMISOLLE WA, AZZARONI O
  • 作者关键词:   heterofunctional scaffold, graphene, supramolecular, antibody, covid19, sarscov2 spike protein
  • 出版物名称:   ACS APPLIED MATERIALS INTERFACES
  • ISSN:   1944-8244 EI 1944-8252
  • 通讯作者地址:  
  • 被引频次:   8
  • DOI:   10.1021/acsami.1c12142 EA SEP 2021
  • 出版年:   2021

▎ 摘  要

Graphene is a two-dimensional semiconducting material whose application for diagnostics has been a real game-changer in terms of sensitivity and response time, variables of paramount importance to stop the COVID-19 spreading. Nevertheless, strategies for the modification of docking recognition and antifouling elements to obtain covalent-like stability without the disruption of the graphene band structure are still needed. In this work, we conducted surface engineering of graphene through heterofunctional supramolecular-covalent scaffolds based on vinylsulfonated-polyamines (PA-VS). In these scaffolds, one side binds graphene through multivalent pi-pi interactions with pyrene groups, and the other side presents vinyl-sulfonated pending groups that can be used for covalent binding. The construction of PA-VS scaffolds was demonstrated by spectroscopic ellipsometry, Raman spectroscopy, and contact angle measurements. The covalent binding of -SH, -NH2, or -OH groups was confirmed, and it evidenced great chemical versatility. After field-effect studies, we found that the PA-VS-based scaffolds do not disrupt the semiconducting properties of graphene. Moreover, the scaffolds were covalently modified with poly(ethylene glycol) (PEG), which improved the resistance to nonspecific proteins by almost 7-fold compared to the widely used PEG-monopyrene approach. The attachment of recognition elements to PA-VS was optimized for concanavalin A (ConA), a model lectin with a high affinity to glycans. Lastly, the platform was implemented for the rapid, sensitive, and regenerable recognition of SARS-CoV-2 spike protein and human ferritin in lab-made samples. Those two are the target molecules of major importance for the rapid detection and monitoring of COVID-19-positive patients. For that purpose, monoclonal antibodies (mAbs) were bound to the scaffolds, resulting in a surface coverage of 436 +/- 30 ng/cm(2). KD affinity constants of 48.4 and 2.54 nM were obtained by surface plasmon resonance (SPR) spectroscopy for SARS-CoV-2 spike protein and human ferritin binding on these supramolecular scaffolds, respectively.