Article

QSPR Study of Fluorescence Wavelengths (λex/λem) Based on the Heuristic Method and Radial Basis Function Neural Networks

QSAR & Combinatorial Science (Impact Factor: 1.55). 10/2005; 25(2):147 - 155. DOI: 10.1002/qsar.200510142

ABSTRACT The Quantitative Structure–Property Relationship (QSPR) method was performed to study the fluorescence excitation wavelengths (λex) and emission wavelengths (λem) of 64 fluorescent probes. The probes included the derivatives of dansyl, bimane, pyrene, benzofurazan, nonaphthalene, coumarin, anthracene and fluorescein, with the wavelength ranging from 300 nm to 600 nm. The Heuristic Method (HM) and Radial Basis Function Neural Networks (RBFNNs) were employed to construct linear and nonlinear prediction models, respectively. The proposed linear models for λex and λem contain five descriptors with the squared correlation coefficients R2 of 0.888 and 0.897, respectively. Better prediction results were obtained from RBFNN model, with the squared correlation coefficients R2 of 0.948 and 0.939 for λex and λem, respectively. The descriptors used in the models were discussed in detail too.

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