Microscope observation of PC12 cells after treated with NGFP membranes containing different NGF layers for 1, 3, 5 days.

<p>NGF at a concentration of 25 ng/mL was used as the positive control. The arrows indicate neuritis associating with differentiation of PC12 cells. The scale bar is 50 μm.</p

Characteristics of TP membranes.

<p>Characteristics of TP membranes.</p

SEM images of NGF membrane.

<p><b>PCL membrane is used as a control</b>. a) PCL membrane; b) NGFP membrane.</p

Surface sulfur content of NGFP nanofiber membrane by energy disperse.

<p>Surface sulfur content of NGFP nanofiber membrane by energy disperse.</p

SEM images of TP membranes and their diameter distribution analysis.

<p><b>PCL membrane is used as a control</b>. a) TP7, b)TP9; c) TP11; d) PCL; e-h) size distribution of TP7, TP9 TP11 and PCL, respectively.</p

Anti-tumor effect of TP7-NGFP-TP7 device against C6 cells.

<p><b>TP7 and PCL membrane were used as controls</b>. The blank indicates the cells without treatment. <b>(*P<0.01; **P<0.001)</b>.</p

<i>In vitro</i> TMZ and protein release profile of TP7-IgGP-TP7 device constructed with TP7.

<p><i>In vitro</i> TMZ and protein release profile of TP7-IgGP-TP7 device constructed with TP7.</p

Contact angle test of nanofiber membranes.

<p>a) PCL membrane and b) NGFP membrane.</p

An illustration of dual-function device designed for dual-stage release of TMZ and NGF.

<p>Notes: TP means TMZ-doped PCL membrane; A means sodium alginate hydrogel; NGFP means NGF-coated PCL membrane.</p