Biosynthesis of gold nanoparticles by using gelatin as reducing and stabilizing agent under ultrasound irradiation: Application of its catalytic activity and for ameliorating motor recovery after spinal cord injury in the Wistar rat’s model

Abstract

The current project describes the facile preparation of Au nanoparticles mediated by gelatin as a natural capping and reducing agent in mild condition. The formation of Au nanoparticles stabilized by gelatin (Au NPs/Gelatin) and structural characteristics were studied via UV–Vis, FT-IR, TEM, FE-SEM, EDX and elemental mapping techniques. The evidence shown that gelatin-capped gold nanoparticles resulted in the lowest average particle sizes of 15–25 nm and spherical shapes nanoparticles. Further, newly synthesized Au NPs/Gelatin are used as a nanocatalyst for the reduction of 4-nitrophenol (4-NP) dyes. A UV–Vis spectrophotometer is employed to track the effectiveness of the reduction process. Recyclability in six further degradation cycles is used to assess the sustainability of this catalyst, and the results show a steady and notable degradation activity. In the in vivo experiment, 60 male rats were classified into four groups: control, intact, sham, and Au NPs/Gelatin nanocatalyst (20 µg/kg) groups. The Hematoxylin and eosin staining was conducted to examine the post-injury lesions. Additionally, somatosensory evoked potential experiments were conducted to assess the recovery of neural conduction. The expression of GFAP was evaluated to determine the extent of astrogliosis. Furthermore, the behavioral outcomes of the rats were evaluated using the BBB scores on a weekly basis after the spinal cord injury onset. The results of the research demonstrated that the neuroprotective effects of Au NPs/Gelatin nanocatalyst led to an amelioration in the rat’s model. Electromyography (EMG) data revealed a remarkable amelioration in hindlimb function in the Au NPs/Gelatin nanocatalyst (20 µg/kg) group. The ventral motor neurons number significantly raised, while the cavity areas significantly decreased in the Au NPs/Gelatin group. Moreover, the expression of GFAP was notably reduced in the Au NPs/Gelatin nanocatalyst group. The Au NPs/Gelatin nanocatalyst group exhibited a significant reduction in delayed responses and a significant increase in BBB scores during sensory tests.