Motif‐Designed Peptide Nanofibers Decorated with Graphene Quantum Dots for Simultaneous Targeting and Imaging of Tumor Cells

Abstract

Nanohybrids based on biomolecular nanostructures and graphene quantum dots (GQDs) have found wide application in the biological and biomedical fields. Herein, the design of a peptide with trifunctional motifs is reported as the precursor building block for constructing a novel multifunctional protein nanofiber (PNF), and further conjugated with highly fluorescent GQDs by noncovalent interactions. The physicochemical properties of these PNF–GQD nanohybrids are thoroughly characterized by a variety of spectroscopic and microscopic techniques, revealing that the GQDs essentially maintain their favorable optical properties in the nanohybrids. A good biocompatibility of the PNF–GQD nanohybrids is found with cell viability assays. With both, a recognition moiety (RGD) and an imaging probe (GQD), these PNF–GQD nanohybrids possess the capability of targeting and imaging tumor cells simultaneously. A potential application of these novel nanohybrids, i.e., fluorescence imaging of HeLa tumor cells, has been investigated by confocal fluorescence microscopy, which shows much enhanced labeling efficiency compared with GQDs only. Moreover, cellular internalization by nontumorous COS‐7 cells was much weaker than by HeLa cells. Our results show that GQD‐decorated PNF nanohybrids have great potential as multifunctional platforms for biomedical applications, particularly, where the capability of sensitive tracking and efficient labeling is appreciated.

Functional Peptide Nanofibers with Unique Tumor Targeting and Enzyme‐Induced Local Retention Properties

“…[17] Hybrids based peptide nanofibers have been utilized for targeting and imaging tumor cells. [18] Here, we employed a new biocompatible, nonimmunogenic formulation of self-assembling peptide nanofiber precursor (NFP) customized with multiple components to optimize the drug delivery efficiency (Figure 1a). The nanofiber 1) contains a high PEG content that can minimize the removal by the RES, 2) has a high aspect ratio to promote tumor uptake, 3) displays a singlelayered geometry to allow the escape from tumor blood vessel, 4) is surface-decorated with negative charges to infiltrate and saturate tumor, and 5) has the ability to structurally evolve into interfibril network for prolonging the retention on site; an enzyme-induced tumor retention (ETR) effect.…”

Design, fabrication, and biomedical applications of bioinspired peptide–inorganic nanomaterial hybrids

“…39 The sequence YWYAF has the ability to bind with carbon-rich surfaces. 7 To date, many surface modification methods have also been used to enhance the interaction between peptide and various inorganic nanomaterials. As clearly shown in Table 1, we summarized partial bioinspired nanohybrids based on materials, dimensions and referred to their applications.…”

“…In terms of nanostructure, protonated amine groups or functional groups on the peptide molecules or assemblies could act as binding moieties to inspire the seed-mediated growth and well-organized decoration of inorganic nanomaterials including metal nanoparticles (MNPs), carbon materials, and quantum dots (QDs). [4][5][6][7] For example, different from other hybrid structure with NPs attached on the surface of peptide molecules, copper (Cu) nanoclusters inside peptide were observed due to the complexation of triazole groups distributed on a three-arm oligopeptide. 8 From the point of view on performance, the versatility of peptide and the specificity of each inorganic nanomaterial greatly contribute to the homogeneous size, optical stability, enhanced mechanical properties of a hybrid system.…”

Recent Advances in the Synthesis of Graphene-Based Nanomaterials for Controlled Drug Delivery

“…Previously, various nanomaterials, such as nanoparticles [3], polymers [4,5], carbon nanotubes [6], and others [7] have been widely used for the controlled drug delivery and release. With the discovery of graphene in 2004 [8], more efforts have been spent to achieve many biomedical applications with graphene-based nanomaterials [9][10][11][12][13].…”