来啦，JMAT全体成员祝大家“元”气满满，“旦”愿事事都如意！

   虽然步入了崭新的一年，但相信JMAT“粉丝”恒久不变的是对科研事业的热忱之心吧。开启新年第一天最好的方式之一就是欣赏1篇妙文吧！今天为大家奉上：二维材料的光致发光效应和生物传感器应用。下期公众号文章预告：二维材料的光致变色和光电转化。

Luminous composite ultrathin films of CdTe quantum dots/silk fibroin co-assembled with layered doubled hydroxide: Enhanced photoluminescence and biosensor application

CdTe量子点/丝素蛋白与层状双氢氧化物共同组装的超薄发光复合薄膜：光致发光的增强和生物传感器应用

 Authors:  Muhammad Sohail Haroone, Ling Li, Aftab Ahmad, Yaping Huang, Ruili Ma, Ping Zhang, Yuehua Hu, Qari Muhammad Kaleem and Jun Lu*

Volume 4, Issue 2, Pages 165-171

Quantum dots (QDs) luminescent films are extensively applied to optoelectronics and optical devices. However, QDs aggregation results in the quenching of their fluorescence property which limits their practical applications to a greater extent. 

量子点（QDs）发光薄膜广泛应用于光电子和光学器件。然而，QDs聚集导致其荧光性质的猝灭，限制了它们在更大范围的实际应用。

In order to resolvethis issue, 3-mercaptopropionic acid (3-MPA) functionalized Cadmium Tellurium(CdTe) QDs were stabilized by silk fibroin (SF) and co-assembled with layered doubled hydroxide (LDH) to form (QDs@SF/LDH)n ultrathin films (UTFs) viathelayer-by-layer (LBL) technique. 

为了解决这个问题，丝素蛋白（SF）被用于稳定3-巯基丙酸（3-MPA）功能化的碲化镉（CdTe）量子点，并借助逐层（LBL）技术与层状双氢氧化物（LDH）共同组装形成了(QDs @ SF / LDH)n超薄薄膜（UTFs）。

UV-Vis absorption and fluorescence spectroscopy showed a stepwise and normal growth of the films upon increasing the number of deposition cycles. 

UV-Vis吸收和荧光光谱表明，随着逐层沉积循环次数的增加，薄膜逐步正常生长。

XRD and AFM studies confirmed the formation of a periodic layered structure and regular surface morphology of the thin films.

XRD和AFM研究证实了薄膜的周期性层状结构和规则表面形貌。

As compared to (CdTe QDs/LDH)nUTFs, the (CdTeQDs@SF/LDH)nUTFs displayed fluorescence enhancement and longer fluorescent lifetime, both in solid states and aqueous solutions. 

与(CdTe QDs / LDH)nUTFs相比，(CdTe QDs @ SF / LDH)nUTFs在固态和水溶液中均显示出荧光增强和更长的荧光寿命。

Furthermore compared with the solution state, the fluorescence enhancement of SF-RC and SF-β are, respectively, 7 times and 17 times in the (CdTeQDs@SF/LDH)n UTFs, indicating that the LDH nanosheets favor the fluorescence enhancement effect on the CdTeQDs@SF. 

此外，与溶液状态相比，(CdTe QDs @ SF / LDH)nUTFs中SF-RC和SF-β的荧光增强分别为7倍和17倍，表明LDH纳米片有利于CdTe QDs @ SF的荧光增强。

The fabricated materials displayed fluorescence response to abiological molecule such as immuneglobulin, lgG. Thus, the (CdTeQDs@SF/LDH)n UTFs has a potential to be used as biosensor.

所制备的材料对生物分子（例如免疫球蛋白，lgG）显示出荧光响应。因此，(CdTe QDs @ SF / LDH)nUTFs有望被用作生物传感器。

文中部分图片：

紫外-可见光吸收光谱

Fig. 1. (Left) UV–Vis absorption spectra. (Inset) Plots of absorbance at 280 nm and 530 nm versus assembly number n, (Right) Fluorescence spectra of (CdTe QDs@SF/LDH)n (n = 5–30) UTFs. (Inset) Plots of fluorescence intensity at 610 nm versus assembly number n.

形貌和物相结构

Fig. 2. Small-angle XRD pattern for the (CdTe QDs@SF/LDH)40 UTF (inset) tapping-mode AFM topographical image of (CdTe QDs@SF/LDH)5 UTF, with a random scanning area for 5 × 5 μm.

荧光时间

Fig. 3. Fluorescence lifetime of the CdTe QD aqueous solution (QD-H2O) (black) and CdTe QD/SF mixed solution (QD-SF-RC) (red).

丝素蛋白对量子点的发光性能影响

Fig. 4. (A) Plots of fluorescence intensity of the three UTFs versus assembly number n (n = 5–30). (b) Fluorescence spectra of the three kinds of UTFs with 30 assembly layers (inset) Digital photos of three kinds of UTFs under ultraviolet lamp.

对免疫球蛋白lgG的荧光响应

Fig. 5. Fluorescence spectra of (a) (CdTe QD/LDH)30 UTF and (b) (CdTe QD@SF/LDH)30UTF in different concentrations of immunoglobulin (IgG) solution (c) Linear relationship of fluorescence intensity of the two UTFs versus the concentration of immunoglobulin (IgG) for (CdTe QD@LDH)30 UTF and (CdTe QD@SF/LDH)30UTF.

LDH对 (CdTe QD@SF/LDH)30UTF荧光稳定性的影响

Fig. 6. Fluorescence spectra of (a) (CdTe QD@SF/LDH)30 UTF (b) (CdTe QD@SF/PDDA)30UTF after different UV lamp irradiation time (c) fluorescence intensity versus UV lamp irradiation time of the UTFs.

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    最后再向大家介绍一下我们闪亮亮的JMAT期刊。它的全称是Journal of　Materiomics，是由中国硅酸盐学会和Elsevier合作出版的英文期刊,现已在ScienceDirect上发布了第四卷第四期（2018年），点击文末“阅读全文“可自由获取所有论文全文。