L-半胱氨酸配位合成CdTe量子点的理论研究

Theoretical study on the synthesis of CdTe quantum dots by L-cysteine coordination

摘要:

本文利用密度泛函理论，研究了L-半胱氨酸及L-胱氨酸在CdTe上的吸附特征. 优化之后分别得到了四种稳定的吸附构型，计算了它们的吸附能、电荷密度、前沿分子轨道以及紫外可见吸收光谱等. 研究发现:L-半胱氨酸在CdTe上的吸附能较大、紫外可见光吸收较强，说明L-半胱氨酸在CdTe上的吸附较稳定，容易产生分子荧光，而L-半胱氨酸转化为L-胱氨酸之后，吸附稳定性降低、紫外可见光吸收强度减弱. 该研究为L-半胱氨酸配体合成的CdTe QDs荧光材料用于生物体内H2O2和葡萄糖的检测提供了理论支撑.

Abstract:

In this paper, the adsorption characteristics of L-cysteine and L-cystine on CdTe was studied by using the density functional theory. Four stable adsorption configurations were optimized, and their adsorption energies, charge densities, frontier molecular orbits and UV-Vis spectra were calculated. It is found that, when the L-cysteine is adsorbed on CdTe, the adsorption energy is large and the absorption to UV-Vis light is strong, indicating that the adsorption of L-cysteine on CdTe is stable and easy to produce molecular fluorescence. After L-cysteine is converted into L-cystine, the adsorption stability is decreased and the absorption intensity to UV-Vis light is weakened. This study provides theoretical support for the application of L-cysteine mediated synthesis of CdTe QDs fluorescence material in the detection of H2O2 and glucose in biochemical analysis.