Limits...
Synthesis of double-clickable functionalised graphene oxide for biological applications.

Mei KC, Rubio N, Costa PM, Kafa H, Abbate V, Festy F, Bansal SS, Hider RC, Al-Jamal KT - Chem. Commun. (Camb.) (2015)

Bottom Line: Fourteen-percentage increase in azide content was found, after pre-treatment of GO with meta-chloroperoxybenzoic acid (mCPBA), determined with elemental analysis.No effect on A549 cell viability was found, up to 100 μg mL(-1) and 72 h of incubation, determined with the modified lactate dehydrogenase (mLDH) assay.The final conjugate was characterised with ATR-FTIR and TGA.

View Article: PubMed Central - PubMed

Affiliation: Institute of Pharmaceutical Science, King's College London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NH, UK. khuloud.al-jamal@kcl.ac.uk.

ABSTRACT
Azide- and alkyne-double functionalised graphene oxide (Click(2) GO) was synthesised and characterised with attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), thermogravimetric analysis (TGA) and Raman spectroscopy. Fourteen-percentage increase in azide content was found, after pre-treatment of GO with meta-chloroperoxybenzoic acid (mCPBA), determined with elemental analysis. No effect on A549 cell viability was found, up to 100 μg mL(-1) and 72 h of incubation, determined with the modified lactate dehydrogenase (mLDH) assay. Two sequential copper(i) catalysed azide-alkyne cycloaddition (CuAAC) reactions were performed to conjugate the propargyl-modified blood-brain barrier targeting peptide Angiopep-2, and a bis-azide polyethylene glycol (MW = 3500), to the Click(2) GO. The final conjugate was characterised with ATR-FTIR and TGA.

No MeSH data available.


Related in: MedlinePlus

Modified LDH assay of A549 cells incubated with GO, GO-N3, Click2 GO, ANG-GO, and ANG-GO-PEG. The toxicity was assessed using the modified LDH assay. No significant effect on cell viability was observed in GO, CO-N3, and Click2 GO. Lower viability was observed in ANG-GO at 50 and 100 μg mL–1 at 72 h (p < 0.001). (*p < 0.05; ***p < 0.001). The viability was recovered in ANG-GO-PEG.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4594119&req=5

fig4: Modified LDH assay of A549 cells incubated with GO, GO-N3, Click2 GO, ANG-GO, and ANG-GO-PEG. The toxicity was assessed using the modified LDH assay. No significant effect on cell viability was observed in GO, CO-N3, and Click2 GO. Lower viability was observed in ANG-GO at 50 and 100 μg mL–1 at 72 h (p < 0.001). (*p < 0.05; ***p < 0.001). The viability was recovered in ANG-GO-PEG.

Mentions: Optical microscopy images of A549 incubated with GO, GO-N3, Click2 GO, ANG-GO, and ANG-GO-PEG were taken at 24 and 72 h time points. Cells incubated with functionalised GO showed normal morphology at all concentrations tested, while cells treated with DMSO appeared unhealthy and detached from the plate (Fig. S13, ESI†). Click2 GO then GO-N3 appeared to interact better with cells compared to plain GO sheets, as shown by the dark signals localised to cells. The extent of GO uptake was concentration and time-dependent (Fig. S14 and S15, ESI†). This interaction was further enhanced in both ANG-GO and ANG-GO-PEG (Fig. S16 and 17, ESI†). The modified lactate dehydrogenase (LDH) assay was used to assess the cytotoxicity of all GO derivatives on A549 cells (adenocarcinoma human alveolar basal epithelial cells) using the method described in SI.46 Cells were incubated with GO, GO-N3, Click2 GO, ANG-GO, and ANG-GO-PEG at 10, 50, and 100 μg mL–1 for 24 and 72 h. Dimethyl sulfoxide (DMSO) was used as a positive control. The cytotoxicity result from the mLDH assay is shown in Fig. 4. No significant effect on cell viability was observed in GO, CO-N3, and Click2 GO. Lower viability was observed in ANG-GO at 50 and 100 μg mL–1 at 72 h (p < 0.001). The viability of GO-ANG was restored when PEGylated (ANG-GO-PEG).


Synthesis of double-clickable functionalised graphene oxide for biological applications.

Mei KC, Rubio N, Costa PM, Kafa H, Abbate V, Festy F, Bansal SS, Hider RC, Al-Jamal KT - Chem. Commun. (Camb.) (2015)

Modified LDH assay of A549 cells incubated with GO, GO-N3, Click2 GO, ANG-GO, and ANG-GO-PEG. The toxicity was assessed using the modified LDH assay. No significant effect on cell viability was observed in GO, CO-N3, and Click2 GO. Lower viability was observed in ANG-GO at 50 and 100 μg mL–1 at 72 h (p < 0.001). (*p < 0.05; ***p < 0.001). The viability was recovered in ANG-GO-PEG.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4594119&req=5

fig4: Modified LDH assay of A549 cells incubated with GO, GO-N3, Click2 GO, ANG-GO, and ANG-GO-PEG. The toxicity was assessed using the modified LDH assay. No significant effect on cell viability was observed in GO, CO-N3, and Click2 GO. Lower viability was observed in ANG-GO at 50 and 100 μg mL–1 at 72 h (p < 0.001). (*p < 0.05; ***p < 0.001). The viability was recovered in ANG-GO-PEG.
Mentions: Optical microscopy images of A549 incubated with GO, GO-N3, Click2 GO, ANG-GO, and ANG-GO-PEG were taken at 24 and 72 h time points. Cells incubated with functionalised GO showed normal morphology at all concentrations tested, while cells treated with DMSO appeared unhealthy and detached from the plate (Fig. S13, ESI†). Click2 GO then GO-N3 appeared to interact better with cells compared to plain GO sheets, as shown by the dark signals localised to cells. The extent of GO uptake was concentration and time-dependent (Fig. S14 and S15, ESI†). This interaction was further enhanced in both ANG-GO and ANG-GO-PEG (Fig. S16 and 17, ESI†). The modified lactate dehydrogenase (LDH) assay was used to assess the cytotoxicity of all GO derivatives on A549 cells (adenocarcinoma human alveolar basal epithelial cells) using the method described in SI.46 Cells were incubated with GO, GO-N3, Click2 GO, ANG-GO, and ANG-GO-PEG at 10, 50, and 100 μg mL–1 for 24 and 72 h. Dimethyl sulfoxide (DMSO) was used as a positive control. The cytotoxicity result from the mLDH assay is shown in Fig. 4. No significant effect on cell viability was observed in GO, CO-N3, and Click2 GO. Lower viability was observed in ANG-GO at 50 and 100 μg mL–1 at 72 h (p < 0.001). The viability of GO-ANG was restored when PEGylated (ANG-GO-PEG).

Bottom Line: Fourteen-percentage increase in azide content was found, after pre-treatment of GO with meta-chloroperoxybenzoic acid (mCPBA), determined with elemental analysis.No effect on A549 cell viability was found, up to 100 μg mL(-1) and 72 h of incubation, determined with the modified lactate dehydrogenase (mLDH) assay.The final conjugate was characterised with ATR-FTIR and TGA.

View Article: PubMed Central - PubMed

Affiliation: Institute of Pharmaceutical Science, King's College London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NH, UK. khuloud.al-jamal@kcl.ac.uk.

ABSTRACT
Azide- and alkyne-double functionalised graphene oxide (Click(2) GO) was synthesised and characterised with attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), thermogravimetric analysis (TGA) and Raman spectroscopy. Fourteen-percentage increase in azide content was found, after pre-treatment of GO with meta-chloroperoxybenzoic acid (mCPBA), determined with elemental analysis. No effect on A549 cell viability was found, up to 100 μg mL(-1) and 72 h of incubation, determined with the modified lactate dehydrogenase (mLDH) assay. Two sequential copper(i) catalysed azide-alkyne cycloaddition (CuAAC) reactions were performed to conjugate the propargyl-modified blood-brain barrier targeting peptide Angiopep-2, and a bis-azide polyethylene glycol (MW = 3500), to the Click(2) GO. The final conjugate was characterised with ATR-FTIR and TGA.

No MeSH data available.


Related in: MedlinePlus