Physicochemical characteristics that affect carbon dot safety: Lessons from a comprehensive study on a nanoparticle library

Abstract

Reagent'ra)o' Carboniza)on'procedure' +/5' Post5func)onaliza)on' Carbon'source' Passiva)on'Agent' 35'carbon'dots' Synthesis'of'a'carbon'dot'library' Dose5dependent'cytotoxicity' Cytotoxicity'and'charge' Cytotoxicity'and'size' Cytotoxicity'and'composi)on' 0.5

Materials promoting viral gene delivery

“…482 This relatively new material class, mostly derived from graphene, has been reported to show size-, charge-, and aggregation-dependent toxicity. 483 In order to stimulate cartilage repair, rAAV coding for the highly chondroreparative SOX9 transcription factor was complexed with various functionalized carbon dots, which resulted in significant increase of transduction to hMSCs with high cell viability. Especially carbon dots functionalized with 2-citric acid, poly(ethylene glycol) monomethyl ether and N,Ndimethylethylenediamine displayed efficient release and TE of rAAV.…”

rAAV-Mediated Overexpression of SOX9 and TGF-β via Carbon Dot-Guided Vector Delivery Enhances the Biological Activities in Human Bone Marrow-Derived Mesenchymal Stromal Cells

“…The various carbon dots (CD-1 to CD-4) were generated through a bottom-up approach, using pyrolysis of citric acid (CA) as the carbon source, in the presence of various additives as passivation reagent: pentaethylenehexamine (PEHA), N,N-dimethylethylenediamine (DMEDA), branched poly(ethyleneimine) 600 Da (bPEI 600 ), poly(ethylene glycol) monomethyl ether 550 Da (mPEG 550 ), or 2 kDa (mPEG 2000 ) [35,38] (Figure 1 and Table 1). Pyrolysis was conducted under conventional heating or microwave irradiation, and the resulting nanoparticles were purified using extensive dialysis against HCl 0.1 N and ultrapure H 2 O (MWCO 1000 Da) [35,38]. The CDs were freeze-dried, and 5.0 mg/mL stock solutions were prepared and stored at 4 • C until use [35,38].…”

“…Pyrolysis was conducted under conventional heating or microwave irradiation, and the resulting nanoparticles were purified using extensive dialysis against HCl 0.1 N and ultrapure H 2 O (MWCO 1000 Da) [35,38]. The CDs were freeze-dried, and 5.0 mg/mL stock solutions were prepared and stored at 4 • C until use [35,38]. The size and charge (zeta potential, ζ) of the nanoparticles were determined using dynamic light scattering (DLS) (NanoSizer NanoZS, Malvern UK) and transmission electron microscopy (TEM) operating at 5 kV (LVEM5, Delong Instruments, Brno, Czech Republic) [35,38] (Table 1).…”

“…The CDs were freeze-dried, and 5.0 mg/mL stock solutions were prepared and stored at 4 • C until use [35,38]. The size and charge (zeta potential, ζ) of the nanoparticles were determined using dynamic light scattering (DLS) (NanoSizer NanoZS, Malvern UK) and transmission electron microscopy (TEM) operating at 5 kV (LVEM5, Delong Instruments, Brno, Czech Republic) [35,38] (Table 1). Cy3 Ab Labeling Kit from Amersham/GE Healthcare (Munich, Germany).…”

“…Thus far, biomaterial-assisted rAAV gene transfer for cartilage research has been described including polymeric micelles [24][25][26][27], hydrogels [28][29][30][31][32] and solid scaffolds [33], yet other materials may constitute valuable systems for rAAV delivery in experimental cartilage therapy. In this regard, carbon dots (CDs), a recently discovered class of carbon-dominated, biocompatible nanomaterials [34,35] used in drug delivery and theranostic approaches [35,36], may be good candidates to achieve this goal as they have been reported for their ability to intracellularly deliver nucleic acids and proteins in vitro [37] and in experimental models in vivo of cancer [38][39][40] and for regenerative medicine [41,42]. It remains to be seen whether CDs are capable of assisting rAAV vector transfer for cartilage repair as such vectors are more effective than nonviral vehicles to deliver genetic material in target cells [10,11].…”