Physical Sciences and Mathematics Commons^™

In a Comment on our recent paper on network glasses (Phys. Rev. Lett., 2003, 90, 085505), Micoulaut and Boolchand (MB) compare our predictions on glass transitions in network systems for the ratios of the transition temperatures TA/TG and TK/TG with experimental data. They claim significant differences between experiment and theory are seen and claim the lack of agreement is due to flaws in our theory. Their comparison of TA/TG is incorrect as they do not measure the same quantity that our theory predicts. The TK/TG comparison shows remarkable agreement between theory and experiment.

The combination of 27Al high-field solid-state NMR (19.6 T) with rapid spinning speeds (17.8 kHz) is used to acquire 27Al NMR spectra of total RNA human brain temporal lobe tissues exposed to 0.10 mM Al3+ (as AlCl3) and of human retinal pigment epithelial cells (ARPE-19), grown in 0.10 mM AlCl3. The spectra of these model systems show multiple Al3+ binding sites, good signal/noise ratios and apparent chemical shift dispersions. A single broad peak (−3 to 11 ppm) is seen for the aluminated ARPE-19 cells, consistent with reported solution-state NMR chemical shifts of Al-transferrin. The aluminated brain tissue has a considerably …