Supporting - Nature

Supplementary Table 2. Elements present as impurities in CNT-2 were determined by ICP-MS (unit: µg/g). Supplementary Figure 1. The hydroxyl radical formation from carbon nanotubes containing different metal contents in different pHs with different reducing agents. Samples contain 0.5 mg/ml CNT-2, 0.1 mM H2O2 and 50 mM DMPO. ................
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