研究目的
To examine the 1O2 sensing efficiency of a fluorescence sensor based on a coumarin–anthracene conjugate and compare it with that of 9-methylanthracene, focusing on the roles of substituents on sensing efficiency.
研究成果
The coumarin–anthracene conjugate sensor shows an order of magnitude lower reactivity to singlet oxygen compared to 9-methylanthracene, attributed to steric effects of the coumarin substituent. This highlights the importance of considering substituent effects, including electronic and steric interactions, in designing efficient fluorogenic sensors for singlet oxygen. Future studies should focus on the roles of exciplex stability and reactivity.
研究不足
The study is limited to specific sensors (coumarin–anthracene conjugate and 9-methylanthracene) and conditions (DMF solvent, Rose Bengal photosensitizer). The role of exciplex intermediates in the reaction kinetics is not fully explored and requires further investigation. Potential optimization could involve testing other substituents or solvents.
1：Experimental Design and Method Selection:
The study uses steady-state absorption and fluorescence measurements to monitor the reaction of sensors with singlet oxygen generated by photosensitization of Rose Bengal. A second-order kinetic model is applied to estimate reaction rates.
2：Sample Selection and Data Sources:
Solutions of the sensor (coumarin–anthracene conjugate, 1) and 9-methylanthracene (2) in dimethylformamide (DMF) are prepared with Rose Bengal as the photosensitizer. Control samples include sodium azide to scavenge singlet oxygen.
3：List of Experimental Equipment and Materials:
UV-Visible spectrophotometer (Evolution 220, ThermoFisher Scientific), fluorescence spectrophotometer (Spectrofluorometer FL4500, Hitachi), DPSS 532 nm Green laser (Shanghai Dream Laser Technology). Chemicals include 9-methylanthracene, Rose Bengal, 7-amino-4-methyl coumarin, 9-chloromethyl anthracene, DBU, sodium azide, and solvents from various suppliers.
4：Experimental Procedures and Operational Workflow:
Samples are irradiated with a 532 nm laser at 50 mW cm?2 for specific time intervals. Absorption and fluorescence spectra are recorded before and after irradiation. Synthesis of a model compound (3) is performed for comparison.
5：Data Analysis Methods:
The rate of reaction is determined using the integral form of the second-order rate equation, with linear fitting of kinetic plots to estimate rate constants.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容-
UV-Visible spectrophotometer
Evolution 220
ThermoFisher Scientific
Recording absorption spectra of samples during the reaction with singlet oxygen.
-
Fluorescence spectrophotometer
Spectrofluorometer FL4500
Hitachi
Recording fluorescence spectra to monitor fluorescence enhancement or depletion during singlet oxygen sensing.
-
DPSS Green laser
Not specified
Shanghai Dream Laser Technology
Photoirradiation of samples at 532 nm to generate singlet oxygen via photosensitization of Rose Bengal.
-
Rose Bengal
Not specified
Tokyo Chemical Industries (TCI)
Photosensitizer for generating singlet oxygen upon irradiation with 532 nm light.
-
9-Methylanthracene
Not specified
Tokyo Chemical Industries (TCI)
Standard compound for comparison of singlet oxygen sensing rates.
-
7-Amino-4-methyl coumarin
Not specified
Tokyo Chemical Industries (TCI)
Precursor for synthesizing the model compound and part of the sensor conjugate.
-
9-Chloromethyl anthracene
Not specified
Merck
Chemical used in synthesis processes, possibly for derivatization.
-
DBU
Not specified
Merck
Catalyst in the synthesis of model compound 3.
-
Sodium azide
Not specified
Merck
Singlet oxygen scavenger in control experiments to confirm specificity of reactions.
-
Dimethylformamide
Not specified
FUJIFILM Wako Pure Chemical Corporation
Solvent for preparing sample solutions.
-
登录查看剩余8件设备及参数对照表
查看全部
