Early detection and treatment of cancer depends on developing highly sensitive and specific methods for targeting cancer cells. To do this, aptamers, which are generated by a novel technique caUed ceU-SELEX （systematic evolution of ligands by exponential enrichment）, have been widely applied in cancer cell targeting based on such merits as high target affinity and specificity, small size, minimal immunogenicity, and ease of chemical modification. Furthermore, aptamers can gain more flexibility as cancer cell targeting tools when conjugated to nanomaterials, including metallic nanoparticles, quantum dots, silica nanoparticles, and carbon nanomaterials, among others. In this review, we discuss the use of cell-SELEX-based aptamer-nanomaterials conjugates as novel molecular tools for enhanced targeting of cancer cells.
KONG RongMei, CHEN Zhuo, YE Mao, ZHANG XiaoBing & TAN WeiHong State Key Laboratory for Chemo/Biosensing and Chemometrics
In this paper,we proposed a facile and accurate way for controlling multiplex fluorescent logic gates through changing the exciting and the observing wavelengths.As proof-of-principle,a Pb2+-specific DNAzyme probe and a thymine(T)-rich DNA probe were introduced to a double-stranded(ds-)DNA.The addition style of the two ions served as the four inputs by changing the distance of the three fluorophores,6-carboxyfluorescein(FAM),ALEXA 532(ALEXA)and carboxytetramethylrhodamine(TAMRA),all of which were modified on the dsDNA probe.Compared with the previous methods,the present approach needed neither different inputs nor the change of sequence of the probe to achieve multiplex logic gates.Furthermore,the modularity of the strategy may allow it to be extended to other types of logic gates.
TAO JiaZHENG JingLI JiShanZHAO PengLI JuanPingMA ChengYI MeiYANG RongHua
As professional antigen presenting cells, dendritic cells(DCs) greatly determine the quality of the innate and adaptive immunities. Therefore, DC-based immunotherapy has been one of the hotspots in cancer immunotherapy in recent years. Although this unique therapeutic strategy has been approved by U.S. Food and Drug Administration for prostate cancer treatment, the efficacy of DC-based immunotherapy remains to be further improved. Moreover, it is still not completely clear about the immunological basis of DCs, which is another hurdle for the progress of DC-based immunotherapy. Due to their unique physicochemical properties, nanomaterials have shown potentials in addressing these above mentioned problems and have provided important guidelines for optimizing DC-based immunotherapy. However, it is still at the starting stage for this emerging field and there are many critical questions in the rational design of this therapeutic strategy to be answered. Therefore, it is greatly necessary to review and analyze recent progresses in this field. In this review, we mainly focus on the development of various types nanoparticles for DC-based immunotherapy. The existed challenges in this field are also discussed.
To develop the high-performance fluorescent bio-sensors, the metal nanoparticles were employed as nanoquenchers and at- tracted reasonable attention in the design of fluorescent biosensors. In this work, silver nanoparticles （AgNPs） were obtained via reduction of Ag＋ on FAM-labeled DNA template. For the tight binding between AgNPs and DNA, the tem- plate-synthesized AgNPs turned out high quenching efficiency and could be applied as super nanoquenchers to establish the biosensing platform for fluorescent detection. As an example, the template-synthesized DNA-AgNPs conjugates were em- ployed in sensing thiols. By forming S-Ag bonds, thiols interact intensely with AgNPs and replace the FAM-labeled DNA off from the surface of AgNPs, resulting in a fluorescence enhancement. Besides the advantages of lower background and higher signal-to-background ratio （S/B）, the conjugates present better stability, making them applicable in complicated biological fluids. To further evidence the feasibility of sensing thiols in real samples, the thiols in human urine were detected. The total amount of free thiols found in human urine was ranging from 229 μM to 302μM with the proposed sensor. To conclude the reliability, low content of Cys was added and the recovery was 98%-103%.
JIN JianYuOUYANG XiangYuanLI JiShanJIANG JianHuiWANG HaoWANG YongXiangYANG RongHua
