L-半胱氨酸配位合成CdTe量子点的理论研究

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

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.

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.