Reaction rates for both mixtures without S63845 quartz (pure water solution and glycine in water solution) are significantly lower ((3.0 · 10−3[s−1]) and (2.2*10−3[s−1]), respectively). Fig. 2 Kinetics of the

free radicals generation Therefore, the presence of glycine in water does not influence the rate of radical generation as much as the presence of quartz. Additionally, it seems that a combination of both factors enhances the reaction rate significantly – almost twofold. Considerably lower and similar reaction rates of the both tests performed without quartz can be ascribed to free radicals originating only from water hydrolysis (Sahni and Locke 2006). Possibly, additional factors provoke different pathways of radical generation, including initiation and propagation. The mechanism of such reaction can possibly be similar to the one suggested this website by Damm and Peukert (2009). Reaction Products Assessment The time dependent measurements of alanine solution subjected to electric discharge with quartz can be seen in Online Resource 1, S.M. 4, however, the differences observed in the spectrum are possibly attributed mostly to quartz (Apopei et al. 2011; Saikian et al. 2008; Shneider 1978; Bobrowski and Holtzer 2010). It was concluded that under the electric discharge, causing piezoelectric tensions, quartz disintegrates into very small pieces that obscure the analysis of the solutions. Therefore, measurements I-BET151 chemical structure of the crystallites of the whole reaction mixture were

assumed to be more accurate for the reaction interpretation. A blank test of glycine solution without quartz seems to support the thesis that the reaction is mostly quartz dependent—no new bands were visible in the IR spectrum (Online Resource 1, S.M. 5). Despite being the simplest proteinogenic amino acid, glycine is probably one of the most problematic to examine, due to the co-existence

of three different polymorphs (Chernobai et al. 2007; Ferrari et al. 2003). The spectra of glycine—before and after the reaction are represented in Fig. 3, with arrows indicating new visible bands. The full spectrum is presented in Online Resource 1, S.M. 6. However, as the distinction between polymorphic transitions and structural alteration, caused by electric discharge, appears to be unachievable at the current stage of experiment, no further examination of data was attempted. Fig. 3 FTIR-ATR spectra of the glycine—before (red) click here and after the reaction (blue), in different spectral ranges: a 3,300–1,900 cm−1 and b 1,700–400 cm−1. Spectra were offset for clarity For these reasons, the experiment was performed with alanine, as it has only one polymorphic structure. The comparison between spectra before and after the reaction is shown in Fig. 4– again the biggest changes are indicated by arrows and full spectra are presented in Online Resource 1, S.M. 7. It seems that only small amount of alanine underwent the reaction, as the obtained spectrum is largely the spectrum of the substrate.