Control of the pore architecture in three-dimensional hydroxyapatite-reinforced hydrogel scaffolds

Figures & data

Table 1 Nominal compositions of the scaffolds obtained with agarose.

Scaffold	Polymer	Polymer : nCHA	Composition of hydrated scaffolds
	solution conc.	ratio	(%)^a
	(w/v %)		Water	Ceramic	Agarose
A^b L80-(O/F)^c	2.5	20:80	88.10	9.30	2.6
			[88.88]	[8.88]	[2.22]
AM50-(O/F)	3.5	50:50	93.10	3.45	3.45
			[93.45]	[3.27]	[3.27]
AH20-(O/F)	5.0	80:20	93.30	1.30	5.40
			[94.11]	[1.17]	[4.70]

^aComposition determined by thermogravimetry; theoretical values are indicated in brackets.

^bA or G stands for the type of gelling agent used: agarose or gellan, respectively.

^c-O or -F represents the drying procedure: in an oven or freeze drying, respectively.

Figure 1 XRD patterns of nCHA, GL80-F scaffold and gellan.

Figure 2 FTIR spectra of nCHA, GL80-F scaffold and gellan.

Figure 3 Photographs of the GL80, GM50 and GH20 scaffolds.

Figure 4 Photograph and SEM image of the AH20-F scaffold.

Figure 5 SEM images of the AH20-F, AM50-F and AL80-F scaffolds.

Figure 6 SEM images of the GH20-F scaffold at different magnifications.

Figure 7 SEM images of the AH20-F (freeze-dried) and AH20-O (oven-dried) scaffolds.

Figure 8 (a) Hg cumulative intrusion and (b) pore size distribution of the GH20-F, GM50-F, GM50-O and GL80-F scaffolds and nCHA.

Table 2 Bulk, skeletal and solid densities and porosities of lyophilized and oven-dried agarose scaffolds.

	Bulk		Skeletal	Solid	PSKE	PSOL
	dg	dp	dSKE	dSOL	(%)	(%)
AL80-F	0.14	0.18	2.32	3.20	92.2	94.3
AM50-F	0.08	0.09	1.45	2.70	93.8	96.6
AH20-F	0.07	0.07	1.26	2.04	94.4	96.5
AL80-O	0.67	0.61	1.81	3.10	66.3	80.3
AM50-O	0.82	0.73	1.72	2.57	57.5	71.6
AH20-O	1.19	0.92	–	1.77	–	48.0

The densities d_g, d_p and d_SOL were measured with a micrometer, by Hg porosimetry and He-picnometry, with the standard deviations of 0.02, 0.02 and 0.01, respectively. The porosities P_SKE and P_SOL were calculated using equation (1) (SD=0.1) with d_p placed in the numerator and d_SKE or d_SOL in the denominator, respectively.

Figure 9 Porosities of the different pore size domains in freeze-dried scaffolds.

Figure 10 Water uptake of some 3D scaffolds after 24 h averaged over four measurements.