DNAzymes hold promise for gene-silencing therapy, but the lack of sufficient cofactors in the cell cytoplasm, poor membrane permeability, and poor biostability have limited the use of DNAzymes in therapeutics. We report a DNAzyme-MnO2 nanosystem for gene-silencing therapy. MnO2 nanosheets adsorb chlorin e6-labelled DNAzymes (Ce6), protect them from enzymatic digestion, and efficiently deliver them into cells. The nanosystem can also inhibit ¹O2 generation by Ce6 in the circulatory system. In the presence of intracellular glutathione (GSH), MnO2 is reduced to Mn²⁺ ions, which serve as cofactors of 10-23 DNAzyme for gene silencing. The release of Ce6 generates ¹O2 for more efficient photodynamic therapy. The Mn²⁺ ions also enhance magnetic resonance contrast, providing GSH-activated magnetic resonance imaging (MRI) of tumor cells. The integration of fluorescence recovery and MRI activation provides fluorescence/MRI bimodality for monitoring the delivery of DNAzymes.

Fan Huanhuan    Zilong Zhao    Yan Guobei    Xiaobing Zhang    Yang Chao    Hongmin Meng    陈卓    Liu Hui    谭蔚泓    

Angewandte Chemie - International Edition

2015

In this work, we fabricate an efficient and stable photocatalyst system which has superior recyclability even under concentrated acidic conditions. The photocatalyst is prepared by assembling magnetic graphitic nanocapsules, titania (TiO2) and graphene oxide (GO) into a complex system through π-π stacking and electrostatic interactions. Such catalytic complex demonstrates very high stability. Even after dispersal into a concentrated acidic solution for one month, this photocatalyst could still be recycled and maintain its catalytic activity. With methyl orange as the model molecule, the photocatalyst was demonstrated to rapidly decompose the molecules with very high photocatalytic activity under both concentrated acidic and neutral condition. Moreover, this photocatalyst retains approximately 100 wt% of its original photocatalytic activity even after multiple experimental runs, of magnetic recycling. Finally, using different samples from natural water sources and different dyes, this GO/magnetic graphitic nanocapsule/TiO2 system also demonstrates its high efficiency and recyclability for practical application.

Cheng Zhen-Qian    Ding Ding    Nie Xiang-Kun    Xu Yi-Ting    Song Zhi-Ling    Ting Fu    陈卓    谭蔚泓    

Science China Chemistry

2015

Background: Human menopausal gonadotropin (hMG) has contributed many improvements to human assisted reproduction. However, effects of hMG on oocyte development and clinical results remain controversial. Objective: This study was conducted to investigate the effects of hMG on the zona pellucida of oocytes, as well as clinical results in superovulation treatment. Materials and Methods: This retrospective study was performed with 150 cycles of long-protocol treatment using recombinant follicle-stimulating hormone (r-FSH) with or without hMG. The number of retrieved oocytes, fertilization rate, implantation rate, pregnancy rate, and birefringence and thickness of the zona pellucida of oocytes were investigated. Results: No significant differences were existed in r-FSH +hMG, and r-FSH groups in the number of retrieved oocytes (11.99±0.75 vs. 13.9±0.73, p=0.06), maturation rate (84.76% vs. 83.32%, p=0.42), pregnancy rate (37.31% vs. 37.66%, p=0.96), and embryo implantation rate (28.97% vs. 23.26%, p=0.30). However, fertilization rate (82.95% vs. 78.75%; p=0.02) was different. Zona pellucida birefringence was lower in the r-FSH +hMG group than in the r-FSH group (6.70±0.50 vs. 7.04±0.31; p=0.53). Thickness values of the metaphase-II zona pellucida of the r-FSH +hMG group on the first (19.20±0.14 vs. 18.75±0.10; p=0.01) and second (18.69±0.12 vs. 18.17±0.14; p=0.00) days of insemination were both higher than those of the r-FSH group. Conclusion: hMG positively influenced the improvement of oocyte fertilization, as well as the birefringence and thickness of zona pellucida.

Bing He    Cheng Junping    Li Huang    谭蔚泓     Xue Lintao    Wang Shikai   

Iranian Journal of Reproductive Medicine

2015

Aptamers, which can be screened via systematic evolution of ligands by exponential enrichment (SELEX), are superior ligands for molecular recognition due to their high selectivity and affinity. The interest in the use of aptamers as ligands for targeted drug delivery has been increasing due to their unique advantages. Based on their different OPEN ACCESS compositions and preparation methods, aptamer-functionalized targeted drug delivery systems can be divided into two main categories: aptamer-small molecule conjugated systems and aptamer-nanomaterial conjugated systems. In this review, we not only summarize recent progress in aptamer selection and the application of aptamers in these targeted drug delivery systems but also discuss the advantages, challenges and new perspectives associated with these delivery systems.

Jiang Feng    Liu Biao    Jun Lü    Li Fangfei    Defang Li.    Liang Chao    Lei Dang    Liu Jin    Bing He    Badshah Shaikh Atik    Cheng Lü    Xiaojuan He    Baosheng Guo    Xiaobing Zhang    谭蔚泓     Aiping Lü    Ge Zhang   

International Journal of Molecular Sciences

2015

Here, we propose an efficient strategy for enzyme- and hairpin-free nucleic acid detection called an entropy beacon (abbreviated as Ebeacon). Different from previously reported DNA hybridization/displacement-based strategies, Ebeacon is driven forward by increases in the entropy of the system, instead of free energy released from new base-pair formation. Ebeacon shows high sensitivity, with a detection limit of 5 pM target DNA in buffer and 50 pM in cellular homogenate. Ebeacon also benefits from the hairpin-free amplification strategy and zero-background, excellent thermostability from 20 °C to 50 °C, as well as good resistance to complex environments. In particular, based on the huge difference between the breathing rate of a single base pair and two adjacent base pairs, Ebeacon also shows high selectivity toward base mutations, such as substitution, insertion, and deletion and, therefore, is an efficient nucleic acid detection method, comparable to most reported enzyme-free strategies.

Lv Yifan    Cui Liang    Peng Ruizi    Zilong Zhao    Liping Qiu    Chen Huapei    Jin Cheng    Xiaobing Zhang    谭蔚泓    

Analytical Chemistry

2015

Cell types, both healthy and diseased, can be classified by inventories of their cell-surface markers. Programmable analysis of multiple markers would enable clinicians to develop a comprehensive disease profile, leading to more accurate diagnosis and intervention. As a first step to accomplish this, we have designed a DNA-based device, called "Nano-Claw". Combining the special structure-switching properties of DNA aptamers with toehold-mediated strand displacement reactions, this claw is capable of performing autonomous logic-based analysis of multiple cancer cell-surface markers and, in response, producing a diagnostic signal and/or targeted photodynamic therapy. We anticipate that this design can be widely applied in facilitating basic biomedical research, accurate disease diagnosis, and effective therapy. © 2013 American Chemical Society.

Mingxu You    Lu Peng    Shao Na    Liqin Zhang    Liping Qiu    Cui Cheng    谭蔚泓    

Journal of the American Chemical Society

2014

The development of nanomaterials that combine diagnostic and therapeutic functions within a single nanoplatform is extremely important for molecular medicine. Molecular imaging with simultaneous diagnosis and therapy will provide the multimodality needed for accurate diagnosis and targeted therapy. Here, gold-coated iron oxide (FeO@Au) nanoroses with five distinct functions are demonstrated, integrating aptamer-based targeting, magnetic resonance imaging (MRI), optical imaging, photothermal therapy. and chemotherapy into one single probe. The inner FeO core functions as an MRI agent, while the photothermal effect is achieved through near-infrared absorption by the gold shell, causing a rapid rise in temperature and also resulting in a facilitated release of the anticancer drug doxorubicin carried by the nanoroses. Where the doxorubicin is released, it is monitored by its fluorescence. Aptamers immobilized on the surfaces of the nanoroses enable efficient and selective drug delivery, imaging, and photothermal effect with high specificity. The five-function-embedded nanoroses show great advantages in multimodality. Five functions in one probe: A gold-coated iron oxide (Fe O@Au) nanorose with five distinct functions, which integrate aptamer-based targeting, magnetic resonance imaging (MRI), optical imaging, photothermal and chemotherapy into one single probe is developed. This multifunctional nanoplatform is used for cancer cell targeting, dual molecular imaging, and dual therapy, with enhanced specific binding, improved cellular uptake, minimum nonspecific toxicity, and side effects. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Li Chunmei    Tao Chen    Ismail Öçsoy I    Guizhi Zhu    Yasun Emir    Mingxu You    Cuichen Wu.    Jing Zheng    Erqun Song    Cheng zhi Huang    谭蔚泓    

Advanced Functional Materials

2014

An artificial nucleic acid analogue capable of self-assembly into a duplex merely through hydrophobic interactions is presented. The replacement of Watson-Crick hydrogen bonding with strictly hydrophobic interactions has the potential to confer new properties and facilitate the construction of complex DNA nanodevices. To study how the hydrophobic effect works during the self-assembly of nucleic acid bases, we have designed and synthesized a series of fluorinated nucleic acids (FNA) containing 3,5-bis(trifluoromethyl)benzene (F) and nucleic acids incorporating 3,5-dimethylbenzene (M) as hydrophobic base surrogates. Our experiments illustrate that two single-stranded nucleic acid oligomers could spontaneously organize into a duplex entirely by hydrophobic base pairing if the bases were size-complementary and the intermolecular forces were sufficiently strong. © 2014 the Partner Organisations.

Ruowen Wang    Wang Chunming    曹洋    Zhi Zhu    Chaoyong james Yang    Chen Jianzhong    卿凤翎    谭蔚泓    

Chemical Science

2014

The water-soluble CP was conjugated with a rhodamine spirolactam for the first time to develop a new FRET-based ratiometric fluorescence sensing platform (CP 1) for intracellular metal-ion probing. CP 1 exhibits excellent water-solubility with two well-resolved emission peaks, which benefit ratiometric intracellular imaging applications. © 2014 The Royal Society of Chemistry.

Wu Yong-Xiang    Li Jun-Bin    Liang Li-Hui    Lu Dan-Qing    Jing Zhang    Guojiang Mao    Liyi Zhou    Xiaobing Zhang    谭蔚泓     沈国励    俞汝勤   

Chemical Communications

2014

The post-genomics era has brought about new Omics biotechnologies, such as proteomics and metabolomics, as well as their novel applications to personal genomics and the quantified self. These advances are now also catalyzing other and newer post-genomics innovations, leading to convergences between Omics and nanotechnology. In this work, we systematically contextualize and exemplify an emerging strand of post-genomics life sciences, namely, nanoproteomics and its applications in health and integrative biological systems. Nanotechnology has been utilized as a complementary component to revolutionize proteomics through different kinds of nanotechnology applications, including nanoporous structures, functionalized nanoparticles, quantum dots, and polymeric nanostructures. Those applications, though still in their infancy, have led to several highly sensitive diagnostics and new methods of drug delivery and targeted therapy for clinical use. The present article differs from previous analyses of nanoproteomics in that it offers an in-depth and comparative evaluation of the attendant biotechnology portfolio and their applications as seen through the lens of post-genomics life sciences and biomedicine. These include: (1) immunosensors for inflammatory, pathogenic, and autoimmune markers for infectious and autoimmune diseases, (2) amplified immunoassays for detection of cancer biomarkers, and (3) methods for targeted therapy and automatically adjusted drug delivery such as in experimental stroke and brain injury studies. As nanoproteomics becomes available both to the clinician at the bedside and the citizens who are increasingly interested in access to novel post-genomics diagnostics through initiatives such as the quantified self, we anticipate further breakthroughs in personalized and targeted medicine. © Copyright 2014, Mary Ann Liebert, Inc. 2014.

Kobeissy Firas H.    Gulbakan Basri    Alawieh Ali    Karam Pierre    ZHANG ZHIQUN    Guingab-Cagmat Joy D.    Stefania Mondello    谭蔚泓     Anagli John    Kevin Wang   

OMICS A Journal of Integrative Biology

2014