Synthesis and study of cell-penetrating peptide-modified gold nanoparticles

Abstract

BackgroundIn nanomedicine, gold nanoparticles (AuNPs) have demonstrated versatile therapeutic efficiencies and, in particular, have been developed for the treatment of various cancers due to their high selectivity in killing cancer, not healthy, cells.MethodsIn this study, AuNPs were conjugated with the cell-penetrating peptide Cys-(Arg)8-Asp-Ser (CRRRRRRRRGDS) by direct cross-linking of the cysteine’s thiol group to the gold surface and a fibronectin-derived RGD group was also used due to its efficacy toward cancer cell targeting and possible promotion of healthy fibroblast functions.ResultsUltraviolet–visible absorbance spectrum and transmission electron microscope images of the synthesized peptide-capped AuNPs (PEP-AuNPs) validated the formation of AuNP aggregates. The presence of peptides on AuNPs was confirmed by Fourier transform infrared spectroscopy and quantified by a bicinchoninic acid assay. After being modified with the arginine-rich peptide, the AuNPs possessed a positive charge, as their zeta potential increased from −23.81±8.43 mV to 8 mV on average. In this manner, an easy method to conjugate AuNPs was shown here. Further, MTS assays were performed using healthy human dermal fibroblasts. After 24 hours of treatment with PEP-AuNPs, the cell density increased dramatically to around 25,000 cells/cm2. Results further showed a very high half-maximal inhibitory concentration of 69.2 µM for the PEP-AuNPs (indicating low toxicity).ConclusionThe results showed for the first time the ability of PEP-AuNPs to promote human dermal fibroblast cell viability, which after further investigation, may show an ability to replace cancerous tissue with healthy soft tissue.

COVID-19 diagnosis by SARS-CoV-2 Spike protein detection in saliva using an ultrasensitive magneto-assay based on disposable electrochemical sensor

“…The thiol group present in the ACE2 cysteine reacted with the AuNPs, presumably through a covalent bond [39] , [40] , and this led to a significant decrease in A SPR through the formation of the bioconjugate [41] . In addition, at 209 nm, the band that corresponded to the peptide remained present though at a lower intensity, indicating its presence after binding with AuNPs [42] , [43] . These results point to the formation of the AuNPs-ACE2 bioconjugate.…”

Prospect of cell penetrating peptides in stem cell tracking

“…The possibility of penetrating into biological membrane makes CPPs become novel carriers for intracellular cargo delivery [ 23 , 25 – 29 ]. Compared with chemical molecules, CPPs have lower biological toxicity and higher transduction efficiency [ 30 , 31 ]. Overall, delivery efficiency of the CPPs may be depending on some parameters such as the size of cargo-CPP complex, nature of CPPs, and so on.…”

Anchor, Spacer, and Ligand-Modified Engineered Exosomes for Trackable Targeted Therapy

“…However, unfortunately, most functionalization techniques using targeting candidates include several difficulties in identifying the presence and nature of ligands. In terms of determination of ligands on nanoparticles, bicinchoninic acid protein assay 27 and high-performance liquid chromatography 28 are used widely, but these methods have some hurdles in proving the presence of targeting peptides because exosomes contain diverse proteins have structural vulnerability in various analytical processes.…”