Objective       To evaluate the tensile strength and biocompatibility of a novel nanoscale iron traction suture for ureteral stent.       Methods       The tensile strength of the suture and the resistance of removing common ureteral stent by cystoscopy were measured and compared. Then the nanoscale iron traction suture was implanted into the muscle tissue on the right side of the spine on the back of SD rats (as experimental group)

while the common surgical suture was implanted on the left side (as control group). Specimens were taken at 1

2

4

6

8 and 12 weeks after implantation

stained with hematoxylin and eosin

and observed by light microscopy. A histological grading scale was used to evaluate the tissue reaction to the 2 implants by examining the thickness and quality of the reaction capsule surrounding the implants

and the quality of the interface. The results were analyzed between the 2 groups.       Results       The tensile strength of the nanoscale iron traction suture was significant greater than the resistance of removing ureteral stent (P0.05). The surrounding tissues of the both implants showed a typical chronic inflammatory reaction caused by foreign body. The 2 implants were surrounded by mononuclear phagocyte infiltration

and some foreign body giant cells were seen which had devoured the suture or the nanoscale iron suture. The histological grading showed there was statistical different between the 2 groups on the thickness of the reaction capsule surrounding the implants and the quality of the interface at 1 week after implantation (P0.05)

but no significant differences were seen in the histological score between the 2 groups at the other periods (P0.05).       Conclusion       The nanoscale iron traction suture possesses good tensile strength and biocompatibility.