The Optoelectronic Nose: Colorimetric and Fluorometric Sensor Arrays

Area of Science:

• Analytical Chemistry
• Chemical Sensing
• Optical Sensors

Background:

• Chemical sensing detects environmental changes using molecular or ionic species.
• Optical sensor arrays utilize chemoresponsive colorants (dyes, pigments) to probe analyte reactivity.
• These arrays function similarly to the olfactory system, employing pattern recognition for specificity.

Purpose of the Study:

• To review the development and state-of-the-art of colorimetric and fluorometric sensor arrays.
• To discuss the design of sensor arrays and their analytical instrumentation.
• To present and critique chemometric and statistical analyses for high-dimensional sensor data.

Main Methods:

• Utilizing arrays of chemoresponsive colorants to generate high-dimensional data from color/fluorescence changes.
• Employing various chemometric and statistical analyses (HCA, PCA, LDA, SVMs, ANNs) for data interpretation.
• Reviewing sensor array design and instrumentation for gas and liquid phase analysis.

Main Results:

• Sensor arrays achieve high sensitivity (ppb levels) and discriminate between similar analytes.
• They enable exquisite fingerprinting of complex mixtures.
• Applications span environmental monitoring, food quality, biosensing, and disease biomarker detection.

Conclusions:

• Colorimetric and fluorometric sensor arrays provide powerful tools for sensitive and specific chemical detection.
• Pattern recognition analysis of high-dimensional data is key to their performance.
• These arrays have broad applicability across scientific and industrial fields.