TY - JOUR
T1 - Ultrabright Red-Emitting Photostable Perylene Bisimide Dyes
T2 - New Indicators for Ratiometric Sensing of High pH or Carbon Dioxide
AU - Pfeifer, David
AU - Klimant, Ingo
AU - Borisov, Sergey M.
PY - 2018/7/25
Y1 - 2018/7/25
N2 - New pH-sensitive perylene bisimide indicator dyes were synthesized and used for fabrication of optical sensors. The highly photostable dyes show absorption/emission bands in the red/near-infrared (NIR) region of the electromagnetic spectrum, high molar absorption coefficients (up to 100 000 m−1 cm−1), and fluorescence quantum yields close to unity. The absorption and emission spectra show strong bathochromic shifts upon deprotonation of the imidazole nitrogen atom, which makes the dyes promising as ratiometric fluorescent indicators. Physical entrapment of the indicators into a polyurethane hydrogel enables pH determination at alkaline pH values. It is also shown that a plastic carbon dioxide solid-state sensor can be manufactured by immobilization of the pH indicator in a hydrophilic polymer, along with a quaternary ammonium base. The influences of the plasticizer, different lipophilic bases, and humidity on the sensitivity of the sensor material are systematically investigated. The disubstituted perylene, particularly, features two deprotonation equilibria, enabling sensing over a very broad pCO2 range of 0.5 to 1000 hPa.
AB - New pH-sensitive perylene bisimide indicator dyes were synthesized and used for fabrication of optical sensors. The highly photostable dyes show absorption/emission bands in the red/near-infrared (NIR) region of the electromagnetic spectrum, high molar absorption coefficients (up to 100 000 m−1 cm−1), and fluorescence quantum yields close to unity. The absorption and emission spectra show strong bathochromic shifts upon deprotonation of the imidazole nitrogen atom, which makes the dyes promising as ratiometric fluorescent indicators. Physical entrapment of the indicators into a polyurethane hydrogel enables pH determination at alkaline pH values. It is also shown that a plastic carbon dioxide solid-state sensor can be manufactured by immobilization of the pH indicator in a hydrophilic polymer, along with a quaternary ammonium base. The influences of the plasticizer, different lipophilic bases, and humidity on the sensitivity of the sensor material are systematically investigated. The disubstituted perylene, particularly, features two deprotonation equilibria, enabling sensing over a very broad pCO2 range of 0.5 to 1000 hPa.
KW - carbon dioxide
KW - dyes/pigments
KW - fluorescence
KW - ratiometry
KW - sensors
UR - http://www.scopus.com/inward/record.url?scp=85050585906&partnerID=8YFLogxK
U2 - 10.1002/chem.201800867
DO - 10.1002/chem.201800867
M3 - Article
AN - SCOPUS:85050585906
SN - 0947-6539
VL - 24
SP - 10711
EP - 10720
JO - Chemistry - a European Journal
JF - Chemistry - a European Journal
IS - 42
ER -