Identification of Chiral-Specific Carbon Nanotube Binding Peptides Using a Modified Biopanning Method

Abstract

Peptides can recognize and selectively bind to a wide variety of materials dependent on both their surface properties and the environment. Biopanning with phage or cell peptide display libraries can identify material-specific binding peptides. However, the limitations with sequence diversity of traditional bacteriophage (phage) display libraries and loss of unique phage clones during the amplification cycles results in a smaller pool of peptide sequences identified. False positive sequences tend to emerge during the biopanning process due to highly proliferating, yet nonspecific, phages. In order to overcome this limitation of traditional biopanning methodology, a modified method using high-throughput next generation sequencing (HTS) was tested to select for unique peptides specific to two types of single wall carbon nanotube (SWNTs) sources with varying diameter distribution and chirality. Here, the process, analysis, and characterization of peptide sequences identified using the modified method is further described and compared to a peptide identified in literature using the traditional method. Selected sequences from this study were incorporated in a SWNT dispersion experiment to probe their selectivity to the nanotube diameter. We show that NHTS can uncover unique binding sequences that might have otherwise been lost during the traditional biopanning method.

Rational Design of Peptide Biorecognition Elements on Carbon Nanotubes for Sensing Volatile Organic Compounds

“…To further demonstrate the effect of the peptide conformation, we tested chemiresistors functionalized by different peptides: 12‐mer CNT‐binding peptides (GSVQKLSATPWV (P1), ALNWTELHGQAT (P5), and LADNAFAHRQRC (P8)) identified by the normalized high‐throughput sequencing phage display. [ 62 ] These peptides functionalized the CNTs, and we exposed IPA to these peptide‐functionalized CNT chemiresistors. Figure S3a (Supporting Information) shows the ∆ R / R 0 of the peptide‐functionalized CNT chemiresistors in response to IPA.…”

Peptide-Functionalized Carbon Nanotube Chemiresistors: The Effect of Nanotube Density on Gas Sensing

“…Figure 1 shows the preparation of peptide-functionalized CNT chemiresistors with varying nanotube densities. Two types of CNT chemiresistors, named CCR1 and CCR2, were obtained from the CNT dispersions made with their respective in silico FYYYLLQ (P1) [32] and phage-displayed GSVQKLSATPWV (P2) [34] peptides. The preparation of the peptide-functionalized CNT solution is described in the Section 2.…”

“…Due to these characteristics, peptides have widely functionalized CNTs for selective molecular detection [33]. Here, we use two representative peptide BREs: a peptide from the phage display with a high affinity to CNTs [34] and a peptide from molecular dynamics and machine learning [32]. Both peptides are from generally accepted methods (i.e., biological or computational) to predict and optimize peptide sequences, thus representing our current study's applicability to general peptide-based biorecognition elements.…”