Synthesis and characterization of silver substituted strontium phosphate silicate apatite using solid-state reaction for osteoregenerative applications

Figures & data

Table 1. Grain size of samples calculated via the Scherrer equation from diffraction data

Sample	FWHM	FWHM (Radians)	Size (Angstrom)	Size (nm)
Pure	0.18856	0.0032	436.74	43.67
1x	0.18976	0.0033	434.07	43.41
2x	0.20127	0.0035	409.27	40.93
3x	0.20189	0.0035	408.1	40.81
4x	0.23332	0.004	353.18	35.32

Figure 1. XRD Pattern of pure phase and silver substituted strontium phosphate silicate samples sintered at 800°C

Figure 1a: Relative peak shift in diffraction data recorded with substitution of silver in samples sintered at 800°C

Figure 2: FTIR spectra of pure phase and silver substituted samples sintered at 800°C showing characteristic peaks and bands

Figure 3. SEM Micrographs of (a) pure Phase and (b) silver substituted samples

Table 2. Absorbance and hemolytic ratio of pure phase and silver substituted samples calculated with respect to OD values

Sample	Absorbance (545 nm)			Hemolysis Ratio			Mean	Std. Dev.
DD Water	1.056	1.056	1.058	Positive Control			_	_
Saline	0.053	0.053	0.053	Negative Control
Pure	0.067	0.068	0.0067	1.3958	1.4955	1.3958	1.42	0.057
1x	0.07	0.069	0.069	1.6949	1.5952	1.5952	1.63	0.057
2x	0.073	0.072	0.071	1.994	1.8943	1.7946	1.89	0.1
3x	0.077	0.079	0.076	2.3928	2.5922	2.2931	2.42	0.152
4x	0.084	0.087	0.087	3.0907	3.3898	3.3898	3.29	0.172

Figure 4. Optical photographs of the pure phase samples by hemolytic assay

Figure 5a: a) Antibacterial effect generated by silver substituted samples over S. aureus calculated via CFU. b) Antibacterial effect generated by silver substituted samples over E. Ccoli calculated via CFU

Figure 6. Relative cellular density as observed for different release concentrations of pure phase and silver substituted samples with respect to control

Figure 7. Calculated cell viability as observed for different release concentrations of pure phase and silver substituted samples with respect to control

Figure 8. X-ray diffraction pattern of 2x silver substituted samples after simulated body fluid immersion

Figure 9. FT-IR Spectra of 2x silver substituted samples after simulated body fluid immersion

Figure 10. SEM Micrographs of 2x silver substituted samples after simulated body fluid immersion. after 7 days of immersion