Contact printing of a quantum dot and polymer cross-reactive array sensor

Contact printing of Quantum Dot (QD) and organic polymer (OP) composites is explored as an alternate method of fabricating a cross-reactive chemical sensor array. Sensing layers fabricated by inkjet printing and contact printing methods are compared, showing that contact printing methods demonstrate a more uniform distribution of the QDs and higher signal to noise ratios (SNRs) when exposed to chemical vapors. A cross-reactive array was then fabricated with CdSe QDs and five OPs and exposed to the vapor of 15 common laboratory solvents. Principal component analysis (PCA) of the data showed high dimensionality of the sensor array response and linear discriminant analysis (LDA) produced correct classification of the target analytes in 100% of test cases.