Multi-functional Graphene as a New Theranostic Agent in Biomedicine and an Effective Adsorbent for Safe Drinking Water

干尼(Ganesh Gollavelli)

指導教授 ： 凌永健

國立清華大學/理學院/化學系/博士(2012年)

摘要

Designing multi-functional nanomaterials with emerging properties is a challenging task. There is every concern to employ nanomaterials for the potential breakthrough in biomedical applications such as cellular imaging, diagnosis, and therapeutics. Modern therapeutics preferentially require some specialized delivery systems in order to maximize their therapeutic efficacy of water insoluble drugs, imaging them at cellular level and also to monitor or manipulate with an external magnetic force.
Graphene, a fascinating material has recently emerged with many intriguing properties including electrical, thermal, optical, sensing, high surface area and biocompatibility. The single or fewer layered structure of graphene provides richness for diversified surface chemistry on both sides of the sheet including edges. By considering the advantage of these properties, we synthesized multifunctional graphene (MFG) / smart magnetic graphene (SMG) with multi functions such as magnetic, water-dispersibility, and fluorescent properties using microwave-heated and sonication-assisted process within one minute. The MFG has been demonstrated as a potential fluorescent marker with lower cytotoxicity for both in vitro and in vivo imaging. Further, it was also non-covalently functionalized with near infrared light absorbing photo sensitizer (PS), SiNc4, to impart MFG-PS. The MFG-PS hybrids have shown excellent phototoxicities in killing the cancer cells through less invasive therapeutic treatments, such as, photodynamic and photothermal therapies. In the clinical diagnosis, MFG-PS is capable to locate the diseased area (fluorescence from MFG) as well as employed for photodiagnosis and molecular imaging, known as, photosensitizer fluorescence detection (PFD).
Among many globally pervasive and emerging risks such as, microbial infections, environmental impact of engineered nanomaterials (NM), and inorganic / organic contaminants, incessant supply of potable and safe drinking water is on the top notch. Many efforts have been driven to decontaminate the potable waters. The need for an efficient, cost-effective, robust, and handy technology for the decontamination of downstream water without endangering human health is still tremendous. We tackle these challenges by SMG in a single roof. The SMG possesses increased active adsorption sites with tunable superparamagnetic property, facilitating the adsorption and magnetic separation of aqueous Cr (VI), As (V) and Pb (II) with ~99% removal efficiencies down to 1 ppb level and decontaminant the organic pollutants. In addition to the efficient adsorption capability, SMG also exhibits better disinfecting action towards E. coli bacteria with 100% killing efficacy and low toxicity towards zebrafish without inducing any abnormalities.
Therefore, the discovery of MFG / SMG provides new opportunities in the biomedical field with diversified potential applications such as in biomedical diagnostics, magnetically guided drug / gene delivery, and photothermal / photodynamic therapies as well as in supplying the safe drinking water.

關鍵字

石墨，飲用水和生物醫學

並列摘要

多功能納米材料的設計與新興物業，是一項艱鉅的任務。是每一個關注採用納米材料在醫學領域的應用，如細胞成像，診斷和治療的潛在突破。現代療法的優先需要一些專門的輸送系統，以最大限度地發揮其療效不溶於水的藥物，成像在細胞水平上，他們還監視或與外部的磁力操縱。
石墨，一個迷人的材料最近出現了許多有趣的性質，包括電學，熱學，光學，遙感，高比表面積和生物相容性。石墨的層狀結構的單一或較少提供多元化的表面化學在紙張的兩面，包括邊緣豐富。考慮到這些屬性的優勢，我們合成多功能石墨（MFG）/智能磁性石墨（SMG）的磁性，水分散性，熒光特性，如多在一分鐘之內使用微波加熱和超聲波輔助進程的功能。已被證明在體外和體內成像的細胞毒性較低作為一個潛在的熒光標記的工業。此外，它也是非共價與近紅外光吸收光敏劑（PS），SINC4，傳授MFG-聚苯乙烯功能。股份有限公司-PS的雜交已通過微創的治療方法，如光動力和光熱療法，在殺死癌細胞的優秀phototoxicities。在臨床診斷，MFG-PS是能夠找到病變區域（從工業熒光）以及就業photodiagnosis和分子成像，作為光敏劑，熒光檢測器（PFD）。
在眾多全球範圍內普及和新興的風險，如微生物感染，納米材料對環境的影響（新墨西哥州），無機/有機污染物，飲用水和安全的飲用水供應不斷，是頂尖的。帶動了許多努力來淨化飲水。下游水不危害人體健康的去污效率，成本效益，穩健，和方便的技術的需求仍然是巨大的。我們面對這些挑戰，通過在一個單一的屋頂衝鋒槍。 SMG的具有增加主動可調的超順磁性吸附位，促進水溶液中Cr（VI）的吸附和磁分離，（五），鉛（二）〜99％的去除率下降到1 ppb級和去污劑中的有機污染物。除了高效的吸附能力，SMG也表現出較好的消毒對大腸桿菌的行動，殺害100％，沒有引發任何異常的療效和毒性低，對斑馬魚。
因此，發現了MFG /衝鋒槍在生物醫學領域提供了新的機遇與多元化的應用潛力，如在生物醫學診斷，藥物/基因傳遞磁導，光熱/光動力療法，以及提供安全飲用水。

並列關鍵字

Graphene, Drinking water and Biomedicine

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