Bell Nia C, Doyle Samantha J, Battistelli Giulia, LeGuyader Clare L M, Thompson Matthew P, Poe Ambata M, Rheingold Arnold, Moore Curtis, Montalti Marco, Thayumanavan S, Tauber Michael J, Gianneschi Nathan C
Department of Chemistry & Biochemistry, University of California, San Diego , 9500 Gilman Drive, MC 0343, La Jolla, California 92093, United States.
Department of Chemistry "G. Ciamician", University of Bologna , Via Selmi 2, Bologna, Italy.
Langmuir. 2015 Sep 8;31(35):9707-17. doi: 10.1021/acs.langmuir.5b01822. Epub 2015 Aug 25.
The encapsulation efficiency of high-Tg polynorbornene micelles was probed with a hydrophobic dye 2,6-diiodoboron-dipyrromethene (BODIPY). Changes in the visible absorption spectra of aggregated versus monomeric dye molecules provided a probe for assessing encapsulation. Polynorbornene micelles are found to be capable of loading up to one BODIPY dye per ten polymers. As the hydrophilic block size increased in the polymeric amphiphiles, more of the dye was incorporated within the micelles. This result is consistent with the dye associating with the polymer backbone in the shell of the micelles. The encapsulation rate varied significantly with temperature, and a slight dependence on micellar morphology was also noted. Additionally, we report a 740 μs triplet lifetime for the encapsulated BODIPY dye. The lifetime is the longest ever recorded for a BODIPY triplet excited state at room temperature and is attributed to hindered triplet-triplet annihilation in the high-viscosity micellar shell.
采用疏水性染料2,6-二碘硼二吡咯亚甲基（BODIPY）探究了高玻璃化转变温度聚降冰片烯胶束的包封率。聚集态与单体态染料分子可见吸收光谱的变化为评估包封情况提供了一种探针。发现聚降冰片烯胶束每十个聚合物最多能够负载一个BODIPY染料。随着两亲聚合物中亲水嵌段尺寸的增加，更多的染料被纳入胶束中。该结果与染料在胶束壳层中与聚合物主链缔合相一致。包封率随温度变化显著，并且还注意到对胶束形态有轻微依赖性。此外，我们报道了包封的BODIPY染料的三重态寿命为740微秒。该寿命是室温下BODIPY三重态激发态有记录以来最长的，这归因于高粘度胶束壳层中三重态-三重态湮灭受阻。
