A new approach on the use of mass spectrometry direct-insertion and a quadrupole detector for analysis of organic compounds supported in solid phase has been developed. This is a simple and efficient method based on cleavage due to the thermal-instability of the benzylic group of most commercial resins. The cleavage of supported compounds takes place in the spectrometer as a consequence of the high temperature in the instrument's chamber. These compounds are detected using a similar fragmentation pattern and a molecular ion corresponding to the same compound obtained by traditional synthesis. Polymer degradation fragments do not interfere with the spectrum interpretation, because only a few peaks and low intensities are detected. We report here the identification of different types of compounds supported in Merrifield resin, such as bis-o-aminobenzamides and simple aromatic and aliphatic compounds, using this new approach.

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A within-subjects experiment with eye tracking was implemented to test the consistency of preferences over three repeated choice experiments. The empirical results indicate that after changing the position of the same alternatives in the choice set, participants were consistent with their choices 69 per cent of the time. Moreover, after reverting back to the identical original positions of the alternatives but randomising the order of the choice sets, individuals’ choices were consistent 67 per cent of the time. Eye tracking data revealed that subjects’ visual attention towards the product attributes was also consistent over the sequence of choices. The robustness of these results was further demonstrated by using random parameters models with flexible mixing distributions to calculate willingness-to-pay for the product attributes and compare its consistency across choice experiments.