Cellulose-based fluorescent chemosensor with controllable sensitivity for Fe³⁺ detection.

Area of Science:

• Materials Science
• Polymer Chemistry
• Analytical Chemistry

Background:

• Renewable polymer sensors show promise but suffer from complex preparation and poor sensitivity.
• Existing sensors often utilize organic small molecules, limiting their environmental compatibility and performance.

Purpose of the Study:

• To develop a straightforward and adjustable strategy for fabricating cellulose-based polymer photoluminescence (PL) chemosensors.
• To achieve sensitive and selective detection of Fe3+ ions in aqueous systems using these novel sensors.

Main Methods:

• Fabrication of cellulose-based polymer PL chemosensors via in-situ synthesis of 1,4-dihydropyridine (DHPs) fluorescent rings on cellulose chains using cellulose acetoacetate (CAA).
• Utilized a catalyst-free, room-temperature Hantzsch reaction for DHPs synthesis.
• Investigated the sensing mechanism involving inner filter effect (IFE) and intramolecular charge transfer (ICT).
• Performed theoretical calculations to understand the role of π-conjugated structures in sensitivity.

Main Results:

• The synthesized sensors exhibited bright and stable PL properties due to synergistic conjugation.
• Achieved highly selective, stable, and anti-interference Fe3+ recognition in aqueous solutions.
• Demonstrated a low limit of detection (LOD) of 0.48 μM for Fe3+.
• Confirmed the influence of π-conjugated structure on sensor sensitivity via theoretical calculations.

Conclusions:

• The developed cellulose-based PL chemosensors offer a promising platform for sensitive and selective Fe3+ detection.
• The straightforward Hantzsch reaction strategy facilitates the development of next-generation biomass-based portable sensors.
• This approach holds potential for real-time and on-site detection applications.