Synergistic effects of polyaniline and pulsed electromagnetic field to stem cells osteogenic differentiation on polyvinylidene fluoride scaffold

Figures & data

Table 1. Sequence of the primers used in the real-time RT-PCR analysis at the present study.

Gene	Primer sequences	Size (bp)
β-2-Micro globulin (β 2M)	TGGAAAGAAGATACCAAATATCGA	201
	GATGATTCAGAGCTCCATAGAGCT
Collagen I (Col-I)	TGGAGCAAGAGGCGAGAG	121
	CACCAGCATCACCCTTAGC
Runx2	GCCTTCAAGGTGGTAGCCC	66
	CGTTACCCGCCATGACAGTA
Osteonectin (OSN)	AGGTATCTGTGGGAGCTAATC	224
	ATTGCTGCACACCTTCTC
Osteocalcin (OSC)	GCAAAGGTGCAGCCTTTGTG	80
	GGCTCCCAGCCATTGATACAG
Osteopontin (SSP1)	GACCTGACATCCAGTACCC	183
	GTTTCAGCACTCTGGTCATC

Figure 1. SEM was applied to morphological study of the fabricated PVDF (A) and PVDF-PANI (B) nanofibrous scaffold.

TABLE 2. Tensile results: mechanical properties of the PVDF nanofibrous scaffolds before and after composite with PANI.

Group	Peak stress	Peak strain (%)	Tensile strength	Tensile strain (%)	Tensile modulus
PVDF	1.93 MPa	15.23	1.57 MPa	5.3	48.26 MPa
PVDF-PANI	1.29 MPa	29.56	0.9 MPa	3.25	33.75 MPa

Figure 2. Optical micrographs of the dental pulp stem cells (DPSCs) (A), SEM images of the DPSCs-seeded electrospun PVDF scaffold in the absence (B) and presence of the PEMF exposure (ELF + PVDF) (C), DPSCs-seeded electrospun PVDF-PANI scaffold in the absence (D) and presence of the PEMF exposure (ELF + PVDF) (E) at day 14 while cultured under osteogenic medium.

Figure 3. Cell attachment (A) and protein adsorption (B) assays of the fabricated PVDF and PVDF-PANI nanofibrous scaffold at the presence and absence of the PEMF exposure. The viability and proliferation rate of the DPSCs during 10 days to display non-toxicity and biocompatibility of the PVDF and PVDF-PANI scaffolds and PEMF exposure under basal medium. The significant differences (p<.05) between groups are indicated with star sign.

Figure 4. The ALP activity (A) and calcium content (B) assays of the differentiated DPSCs while cultured on the PVDF and PVDF-PANI under osteogenic medium at the absence and presence of the PEMF at days 7 and 14 after cell seeding. The significant differences (p<.05) between groups are indicated with star sign.

Figure 5. Relative expression of Runt-related transcription factor 2 (Runx2), Collagen type-1 (Col-I), Osteonectin (OSN), Osteocalcin (OSC) and Osteopontin (SPP1) at days 7 and 14 for DPSCs cultured on the PVDF and PVDF-PANI under osteogenic medium at the absence and presence of the PEMF. The significant differences (p<.05) between groups are indicated with star sign.

Figure 6. Immunocytochemistry (ICC) staining for osteocalcin protein in the differentiated DPSCs cultured on the PVDF (B) and PVDF-PANI under osteogenic medium and PEMF (D). DAPI stained of the DPSCs cultured on the PVDF (A) and PVDF-PANI (C).