Synthesis and optical studies of upconverting fluorescent nanomaterials

尽管在过去的世纪中取得了许多进展，但除非促进重大的科学和技术突破，否则社会将在生物医学、法医和安全（指纹检测、爆炸物标记和证件防伪）方面面临严峻的挑战。这些挑战可能受益于纳米技术，包括确定许多疾病的分子起源和早期检测，这两者对于有效治疗至关重要。许多挑战将取决于理解原子和分子聚集体的性质和行为，这些性质与大尺度上的性质有显着差异，以及新纳米材料的合成。我们的研究计划的首要目标是合成镧系元素掺杂的上转换纳米粒子，并表征其物理，结构和化学性质。上转换磷光体由红外辐射（低能量）直接激发，导致可见光或UV发射（高能量）。使用红外辐射是有利的，因为它对细胞的伤害较小，更大程度地穿透组织，并且实际上消除了自体荧光。因此，使这些材料成为生物成像的理想材料。这些镧系元素掺杂的纳米材料也可能是多模式活动的理想平台，如光学成像，治疗和MRI。这是可能的，因为这些材料可以掺杂有不同的镧系元素离子。

Despite the many advances which have occurred over the past century, society will be faced with daunting challenges in biomedicine, forensic and security (fingerprint detection, tagging of explosives and anti forgery of documents) unless major scientific and technological breakthroughs are fostered. These challenges, may benefit from nanotechnology, including identifying the molecular origins of many disease and early detection, both of which are paramount to effective treatment. Many of the challenges will depend on understanding the properties and behavior of aggregate of atoms and molecules at a scale where properties differ significantly from those at the larger scale and on the synthesis of new nanomaterials. The overriding objective of our research program is the synthesis of lanthanide doped upconverting nanoparticles and to characterize their photophysical, structural and chemical properties. An upconverting phosphor is excited by infra red radiation(low energy) directly, leading to visible or UV emission(high energy). The use of infra red radiation is advantageous since it is less harmful to cells, penetrates tissue to a greater extent and virtually eliminates autofluorescence. Thus, making these materials ideal for bioimaging. These lanthanide doped nanomaterials may also be an ideal platform for multi modal activities such as optical imaging, therapeutics and MRI. This is possible since these materials may be doped with different lanthanide ions.