Figure 6 PL spectra of CdTe QDs recorded after reaction 120 min with different reductants. (a) pH = 10.0, nCd2+/nTe2−/nMPA = 1:0.25:2.7 and (b) pH = 10.0, nCd2+/nTe2−/nMPA/nNaBH4 = 1:0.25:2.7:2.7. Conclusions In summary, a facile synthetic route for the preparation of water-soluble CdTe QDs has been proposed using 3-mercaptopropionic acid reduction of TeO2 directly. Since the raw materials are cheap and easy to be obtained, the synthesis process is simple, fast, and mild. The as-synthesized CdTe QDs were highly see more luminescent, which ensures its promising future applications as biological labels. Acknowledgments The authors gratefully acknowledge the support for this research from

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