Naphthalene based colorimetric sensor for bioactive anions: experimental and DFT study

Area of Science:

• Chemical Sensing
• Anion Detection
• Molecular Design

Background:

• Development of selective and sensitive anion sensors is crucial for environmental and biological monitoring.
• Colorimetric sensors offer a simple and cost-effective method for anion detection.

Purpose of the Study:

• To design and synthesize a novel colorimetric sensor (L) for selective anion detection.
• To investigate the sensing mechanism and performance of sensor L towards various anions.

Main Methods:

• Synthesis of sensor L by combining 2-hydroxy-1-naphthaldehyde and 2-aminothiophenol.
• Colorimetric analysis of sensor L in acetonitrile (CH3CN) upon addition of different anions.
• Determination of selectivity and detection limit for target anions.
• Investigation of anion sensing in mixed aqueous-organic media.
• Spectroscopic studies ((1)H NMR) and computational modeling (B3LYP/6-31G(d,p)) to elucidate interaction mechanisms.

Main Results:

• Sensor L exhibited a distinct color change from light green to red in the presence of acetate (AcO-), fluoride (F-), and dihydrogen phosphate (H2PO4-) anions.
• Sensor L demonstrated high selectivity for AcO- over other tested anions (Cl-, Br-, I-, HSO4-) in a competitive environment.
• A low detection limit of 1.1×10(-7) M for AcO- was achieved.
• The anion sensing capability was also observed in mixed H2O/CH3CN media.
• (1)H NMR and computational studies provided insights into the interaction between sensor L and AcO-.

Conclusions:

• The designed sensor L is effective for the selective colorimetric detection of acetate ions.
• The sensor exhibits good sensitivity and selectivity, making it suitable for practical applications.
• Further studies can explore its application in real-world samples and its potential for other anion detections.