Facile synthesis and characterization of Au nanoparticles-loaded kaolin mediated by Thymbra spicata extract and its application on bone regeneration in a rat calvaria defect model and screening system

Figures & data

Figure 1. TEM images of (a) kaolin and (b–d) Au NPs-kaolin nanocomposite.

Figure 2. FE-SEM image of Au NPs-kaolin nanocomposite.

Figure 3. EDX profile of the Au NPs-kaolin nanocomposite.

Figure 4. FE-SEM image of Au NPs-kaolin nanocomposite with its elemental mapping.

Figure 5. X-ray diffraction study of Au NPs-kaolin nanocomposite.

Figure 6. The cytotoxicity effects of HAuCl₄ and Au NPs-kaolin nanocomposite against normal (HUVEC) cell line.

Figure 7. Representative H&E sections depicting the new bone formation (H&E staining, A-P: ×200, inset: ×1000).

Table 1. Histopathological findings related to the foreign body reaction and osteoblastic rimming at 5, 7, 10 and 12 weeks for Au NPs-kaolin nanocomposite, collagen and control groups.

	Weeks	Foreign body reaction	Osteoblastic rimming
Au NPs-kaolin nanocomposite	5	−	+
	7	+	+
	10	+	+
	12	+	+
Collagen	5	−	+
	7	−	+
	10	−	+
	12	−	−
Control	5	−	+
	7	−	+
	10	−	−
	12	−	−

Table 2. Histopathological findings related to the mineralized bone and osteoid at 5, 7, 10 and 12 weeks for Au NPs-kaolin nanocomposite, collagen and control groups.

	Weeks	Mineralized bone	Osteoid
Au NPs-kaolin nanocomposite	5	+	+
	7	+	+
	10	+	+
	12	+	+
Collagen	5	+	+
	7	+	+
	10	+	−
	12	+	−
Control	5	+	+
	7	+	+
	10	+	−
	12	+	−

Table 3. Histopathological findings related to the granulation tissue and inflammation at 5, 7, 10 and 12 weeks for Au NPs-kaolin nanocomposite, collagen and control groups.

	Weeks	Granulation tissue	Inflammation
Au NPs − kaolin nanocomposite	5	+	+
	7	+	+
	10	+	+
	12	+	+
Collagen	5	+	+
	7	+	+
	10	−	−
	12	−	−
Control	5	+	+
	7	+	+
	10	−	−
	12	−	−