Novel fluorinated curcumin-doped silica nano-photosensitizer (SiO2@F-Cur): Preparation, characterization, and preservation effects of photodynamic inactivation on peeled Paciffc white shrimp

To enhance the stability and the photodynamic inactivation (PDI) preservation effect of curcumin (Cur), this study used the Stöber method to prepare a new fluorinated curcumin (F-Cur) doped silica nano-photosensitizer (SiO 2 @F-Cur) through a covalent coupling strategy. The results showed that the water solubility of SiO 2 @F-Cur was 327.00 ± 4.58 µg/mL, which was 3.65-fold that of Cur. The absorbance retention rate of its aqueous solution after blue-light LED irradiation for 30 min was 42.86% (while that of Cur was only 14.08%). At the same time, SiO 2 @F-Cur exhibited excellent singlet oxygen ( 1 O 2 ) generation ability, with a degradation rate of 1,3-diphenylisobenzofuran (DPBF) of 63% within 60 s (compared to only 19% for Cur). In PDI preservation application for peeled Paciffc white shrimp ( L. vannamei ), compared to the control group and Cur treatment group, SiO 2 @F-Cur-mediated PDI treatment group showed the best sensory acceptance, color stability, and moisture retention ability. On the eighth day of storage, its total volatile basic nitrogen (TVB-N) content, pH value, total viable count (TVC) count, and thiobarbituric acid (TBA) value were 18.53 ± 0.15 mg/100 g, 7.13 ± 0.02, 6.33 ± 0.03 log CFU/g, and 0.79 ± 0.02 mg MDA/kg, respectively, which were significantly lower than those of the control group and Cur treatment group ( P < 0.05). High-throughput sequencing results showed that the SiO 2 @F-Cur-mediated PDI treatment could significantly delay the simplification process of the microbial community in shrimp, and effectively inhibit the growth of spoilage bacteria (such as Shewanella ). Therefore, SiO 2 @F-Cur prepared in this study is a stable and efficient new type of nano-photosensitizer, providing new ideas for guiding the development of new aquatic product preservatives.