光敏剂对斜纹夜蛾细胞的光活化杀虫活性、单线态氧及稳定性

[目的]提高光敏剂的光稳定性，延长光敏剂在环境中的半衰期。[方法]该研究以典型光敏剂α-三联噻吩为模板，利用生物等排原理，以苯环代替噻吩环，合成了光敏剂2，5-二苯基噻吩和2，5-二乙炔苯基噻吩，并研究了所合成的光敏剂的对斜纹夜蛾细胞的光活化毒力、单线态氧及光稳定性。[结果]光敏剂2，5-二苯基噻吩对斜纹夜蛾细胞的24和48 h的抑制中浓度IC50值分别为0.22和0.16μg/ml，2，5-二乙炔苯基噻吩斜纹夜蛾细胞的24和48 h的抑制中浓度 IC50值分别为0.06和0.04μg/ml；在紫外光照下，光敏剂2，5-二苯基噻吩和2，5-二乙炔苯基噻吩产生的1O2能力分别为1.0475和1.5294μg/mmol；2，5-二苯基噻吩和2，5-二乙炔苯基噻吩在甲醇中降解动力学方程分别为 Ct=5.2271e-0.061t和 Ct=5.0842e-0.0973t，其半衰期分别为111.79和7.12 h。[结论]所合成的光敏剂2，5-二苯基噻吩具有良好的光活化激发产生单线态氧的能力，对斜纹夜蛾SL细胞具有良好的光活化毒杀作用，克服了光活化杀虫剂见光易分解等不足，因此2，5-二苯基噻吩具有开发成光活化杀虫剂的潜力。

Photoactivated Activities on Spodoptera fitura Cell,Singlet Oxygen and Photostability of Photosensitizers

[Objective ]The aim of this study was to improve the photostability of pho-tosensitizers. [Method] 2,5-Diphenylthiophene and 2,5-dithienylethynylthiophene were synthesized by replacing thiophene rings of α-terthienyl （α-T） with benzene rings. Photoactivated activities on Spodoptera litura （SL） cells, singlet oxygen with UV and photostability of photosensitizers were investigated. [Result] The cytotoxicity of pho-tosensitizer 2,5-diphenylthiophene on SL cells was 0.22 and 0.16 μg/ml after treat-ment for 24 and 48 h, respectively, while that of 2,5-dithienylethynylthiophene on SL cells was 0.06 and 0.04 μg/ml. Singlet oxygen of 2,5-diphenylthiophene and 2,5-dithienylethynylthiophene was 1.047 5, 1.529 4 μg/mmol under UV, respectively. Degradation dynamic equations of 2,5-diphenylthiophene and 2,5-dithienylethynylthio-phene in methanol were Ct= 5.227 1e-0.006 1t, Ct= 5.084 2e-0.097 3t and half life was 111.79, 7.12 h. [Conclusion] Photosensitizer 2,5-diphenylthiophene has high singlet oxygen production ability, and high photoactivated cytotoxicity on SL cells under UV. Moreover, 2,5-diphenylthiophene has overcome the deficiency of photoactivated in-secticides, which is not applied directly in field because it degrades quickly in the environment.