Preparation of brushite cements with improved properties by adding graphene oxide

Figures & data

Figure 1 XRD pattern of beta-tricalcium phosphate and hydroxyapatite.

Figure 2 FTIR pattern of beta-tricalcium phosphate and hydroxyapatite.

Abbreviation: FTIR, Fourier Transform Infrared Spectroscopy.

Figure 3 Structural and morphological characterization of synthesized GO: XRD (A) and AFM (B) of graphene.

Abbreviations: XRD, x-ray diffraction; AFM, Atomic Force Microscopy.

Table 1 Calcium phosphate cement setting time

Sample name	Setting time (min)
CPC	30±0.8
CPC +0.5% GO	26±1.4
CPC +2% GO	23±0.9
CPC +5% GO	17±1.0

Abbreviations: CPC, Calcium Phosphate Cement; GO, graphene oxide.

Table 2 Compressive strength and young modulus of composite cement

CPC/GO	Comperssion Strength (MPa)	Young Modul (GPa)
0%	12	0.4
0.5%	40	0.8
2%	42	0.8
5%	2	0.04

Abbreviations: CPC, Calcium Phosphate Cement; GO, graphene oxide.

Figure 4 Stress-strain curve of composite cement.

Figure 5 XRD patterns of 0.5% (A) and 0% (B) CPC/GO composite.

Abbreviations: CPC, calcium phosphate cement CPC/GO scaffold; XRD, x-ray diffraction.

Figure 6 FTIR patterns of 0% and 0.5% CPC/GO composite.

Abbreviations: CPC, calcium phosphate cement CPC/GO scaffold; FTIR, Fourier Transform Infrared Spectroscopy.

Table 3 pH changes of cements

Sample name	pH	Solution	Time	Temperature
CPC	6.3	PBS	24 h	37 °C
CPC +0.5% GO	6.3	PBS	24 h	37 °C
CPC +2% GO	6.3	PBS	24 h	37 °C
CPC +5% GO	6.3	PBS	24 h	37 °C

Abbreviations: CPC, calcium phosphate cement CPC/GO scaffold; PBS, Phosphate buffered saline.

Table 4 Porosity of cements

Sample name	Porosity %
CPC	61
CPC +0.5% GO	61
CPC +2% GO	62
CPC +5% GO	63

Abbreviation: CPC, calcium phosphate cement CPC/GO scaffold.

Figure 7 FESEM pictures of 0%, 0.5%, 2% and 5% cements after soaking for 7 days.

Abbreviation: FESEM, Emission scanning electron microscopy.

Figure 8 FESEM pictures of 0%, 0.5%, 2% and 5% cements after soaking for 14 days.

Abbreviation: FESEM, Emission scanning electron microscopy.

Figure 9 The cytotoxicity graph of the composite cement extract at intervals of 1, 3 and 7 days (⩽0.05).

Figure 10 FESEM of cements cell attachment after 1 day.

Abbreviation: FESEM, Emission scanning electron microscopy.

Figure 11 ALP activity of the MG63 cells cultured on specimens for 3 and 7 days.

Abbreviations: ALP, Alkaline phosphatase activity; GO, graphene oxide.