A pseudohomogeneous nanocarrier based on carbon quantum dots decorated with arginine as an efficient gene delivery vehicle

Abstract

A pseudohomogeneous carrier as an emerging term refers to subnanometric carbon-based vehicle with a high ability to interact with genetic materials to form stable carboplex and successfully transfer them into the cell which will result in inhibiting or expressing of therapeutic genes. Chitosan is a non-toxic polyaminosaccharide used as a precursor in the presence of citric acid to produce carbon quantum dots (CQDs), which decorated with arginine as a surface passivation agent with high amine density in hydrothermal methodology. The Arginine-CQDs are comprehensively characterized by Fourier-transform infrared spectroscopy (FT-IR), Ultraviolet–visible spectroscopy (UV–vis), Atomic force microscopy (AFM), field emission scanning electron microscope (FE-SEM), Energy-dispersive X-ray (EDX) mapping, fluorescence, High-resolution transmission electron microscopy (HR-TEM), zeta potential and X-ray powder diffraction (XRD). In this regard, for the first time, carboplex are formed by electrostatic conjugating of Arginine-CQDs with DNA to protect it from enzymatic degradation. Moreover, the carboplex, like the chitosan precursor, has not shown toxicity against AGS cell line. Interestingly, the Arginine-CQDs have exhibited an excellent ability to overcome cell barriers to deliver into cells compared to chitosan at the same weight ratio. The Arginine-CQDs/pEGFP (W/W) nanocomplex, not only lead to transfection with a relatively higher efficiency than PEI polymer, which is the “golden standard”, but carboplex also demonstrates no significant toxicity. Indeed, the EGFP expression level has reached to 2.4 ± 0.2 via Arginine-CQDs carboplex at W/W 50 weight ratio. To the best of our knowledge, this is the first report includes chitosan-based CQDs functionalized by arginine which is applied to serve as a pseudohomogeneous vehicle for gene transfection.

Efficient Synthesis of Highly Photo‐stable N‐doped Carbon Quantum Dots and their Applications in Detection and Cellular Imaging of Mercury Ions

“…FTIR spectrum of the N-CQDs was shown in Figure 3b, showing characteristic bands of -OH/NÀ H, C=O/C=C, CÀ N, CÀ OÀ C, and CÀ O at 3420, 1580, 1393, 1273 and 1074 cm À 1 , respectively. [37,38] The FTIR results validated the N-CQDs embedding of the carboxyl, hydroxyl, and amino groups. The presence of hydrophilic groups on the N-CQDs, especially OÀ H and C=O, ensures their hydrophilicity and stability in aqueous systems.…”

Highly Photostable Carbon Dots from Citric Acid for Bioimaging

“…CAArg, in particular, can be usefully applied for efficient gene delivery because of its guanidinium positive local charges as a ligand factor for the negative charges of the gene’s phosphate groups. Some studies have demonstrated the highly efficient delivery of genetic materials to adenokarcinom cells by arginine-C-dot carriers [ 30 ]. Targeting the nucleus with C-dots for drug delivery is essential, especially for cancer treatment.…”

Carbon dots: a novel platform for biomedical applications

“…They concluded that arginine engraftment acts as a CPP, and enhances cellular internalization and consequent transfection. 245 …”