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The emphasis of this study lies in that we present a novel fluorescence scanning approach to evaluate the antioxidant capacity of Fritillaria ussuriensis polysaccharide-zinc (FUP-Zn) complex. FUP was extracted successfully, and the corresponding FUP-Zn complexes with different substitution degrees were obtained after modified chemically with ZnCl2. The physiochemical characteristics of the as-prepared samples were determined by ultraviolet-visible spectroscopy, infrared spectroscopy, X-ray powder diffraction, scanning electron microscope, energy dispersive spectrum, thermo gravimetric-differential thermal analyses and etc., and these characterization results confirmed the successful synthesis of FUP-Zn complexes with good stability. The scavenging ability investigation of FUP-Zn complexes towards hydroxyl radicals and superoxide anion radicals carried out by us has revealed that the integration of FUP and Zn greatly enhanced the antioxidant activity due to the synergistic effect and larger pore size of FUP-Zn complexes, and the antioxidant activity of FUP-Zn complex with different substitution degrees is heavily dependent on the amount of Zn. This study indeed provides vital theoretical basis for the promising antioxidant and zinc supplement evaluation from more novel polysaccharide-zinc complexes with suited Zn amount.

In situ hydrogel has attracted widely attention in hemostasis due to its ability to match irregular defects, but its application is limited by insufficient mechanical strength and long gelation time. Although some specifical in situ chemically cross-linked hydrogels could be fast formed and exhibit high mechanical strength, they unable to absorb blood. Hence their applications were further limited in emergency hemostasis usage. In this study, a robust hydrogel formed by hydration of powders was developed using multiple hydrogen bonds crosslinking. Here, catechol groups modified e-polylysine (PL-CAT) and polyacrylamide (PAAM) were used to construct the PL-CAT/PAAM hydrogel. This hydrogel could be formed within 7 s to adhere and seal bleeding sites. The catechol groups endowed the hydrogel outstanding adhesive strength, which was 3.5 times of fibrin glue. Besides, the mechanical performance of in-situ PL-CAT/PAAM hydrogel was explored and the results showed that the hydrogel exhibited high compressive strength (0.47 MPa at 85% strain). Most importantly, the blood loss of wound treated with PL-CAT/PAAM hydrogel powders was 1/7 of untreated group, indicating the hydrogel's excellent hemostatic effect. And the cytotoxicity studies indicated that the PL-CAT/PAAM hydrogel had low toxicity. To summarize, this hydrogel could be a potential hemostatic material in emergency situations.