Evaluation of Multitransducer Arrays for the Determination of Organic Vapor Mixtures

Abstract

A study of vapor recognition and quantification by polymer-coated multitransducer (MT) arrays is described. The primary data set consists of experimentally derived sensitivities for 11 organic vapors obtained from 15 microsensors comprising five cantilever, capacitor, and calorimeter devices coated with five different sorptive-polymer films. These are used in Monte Carlo simulations coupled with principal component regression models to assess expected performance. Recognition rates for individual vapors and for vapor mixtures of up to four components are estimated for single-transducer (ST) arrays of up to five sensors and MT arrays of up to 15 sensors. Recognition rates are not significantly improved by including more than five sensors in an MT array for any specific analysis, regardless of difficulty. Optimal MT arrays consistently outperform optimal ST arrays of similar size, and with judiciously selected 5-sensor MT arrays, one-third of all possible ternary vapor mixtures are reliably discriminated from their individual components and binary component mixtures, whereas none are reliably determined with any of the ST arrays. Quaternary mixtures could not be analyzed effectively with any of the arrays. A "universal" MT array consisting of eight sensors is defined, which provides the best possible performance for all analytical scenarios. Accurate quantification is predicted for correctly identified vapors.

Molecular recognition using receptor-free nanomechanical infrared spectroscopy based on a quantum cascade laser

“…Therefore, achieving chemical selectivity in a mixture of unknown chemical vapors is extremely difficult without resorting to molecular separation. Even approaches based on sensor arrays immobilized with unique chemical interfaces and subsequent analysis of array response using pattern recognition algorithms fail when it comes to ternary mixtures23456.…”

Chemiresistive Sensing of Volatile Organic Compounds with Films of Surfactant-Stabilized Gold and Gold−Silver Alloy Nanoparticles

“…Discrimination between vapors is possible using sensor arrays comprising MPCs containing different functionalities and principle component analysis, 14 but this is more challenging in complex samples. MPCs have also been used as chemiresistive detectors for GC, 24 which allows multianalyte detection by separation of the sample into the individual components prior to analysis, 66 and with quartz crystal microbalance (QCM) sensors. 13,29,47 This paper describes the first use of films of surfactant-stabilized Au and AuAg nanoparticles (NPs) for chemiresistive sensing of VOCs.…”

Sensor Array Design for Complex Sensing Tasks

“…For example, Grate and colleagues (18,19,(48)(49)(50)(51) have reported extensively on the use of SAW and other sorption-based sensor arrays in detection of chemical vapors. Zellers and colleagues (52)(53)(54)(55) have reported microfabricated arrays of chemiresistor and hybrid arrays applied to binary and ternary chemical mixtures. Suslick and colleagues (56)(57)(58)(59)(60) have reported colorimetric sensor arrays applied to many complex chemical sensing problems.…”