of analytes in vivo for diagnostic sensing
This technology allows for long-time in vivo detection of analytes.
The current device presents a photoluminescent single-walled carbon nanotube based nanosensor, embedded in a hydrogel, which can be used for detection of analytes. Nitric oxide (NO) presents an interesting case study for such a sensor. NO is an important cellular signaling molecule, critical for maintaining vascular physiology and regulating immune defense. In addition, its paradoxical roles in carcinogenesis remain unclear, with experimental results that suggest both pro- and anticancer effects. It has been established that there are two fundamental factors complicating the biological effects of NO in vivo: its concentration and its location of production. Accurate detection of NO is essential to understanding its diverse biological roles. Difficulties arise mainly due to its rapid diffusivity and high reactivity with endogenous molecules, including oxygen, exposed thiols, other free radicals, and heme proteins. In many cases, both the resultant short lifetime and its cellular reaction by products affect the accuracy of detection. Chemical approaches to the detection of nitric oxide or its reaction products have been a constant focus of research in recent years, most commonly the design and synthesis of organic fluorophores or quantum dots that modulate fluorescence upon exposure to NO. In this technology, the first fluorescence-based SWNT sensing array is made of single-stranded d(AT)15 DNA oligonucleotide-wrapped SWNTs (AT15-SWNT). This 30-base oligomer imparts SWNTs with the capability of directly, and selectively, quantifying NO concentrations. It is found that the AT -SWNT15 complex is unique in its high selectivity toward NO when compared with a library of other DNA sequences and polymers. The ability to detect nitric oxide quantitatively at the single-molecule level may find applications in new cellular assays for the study of nitric oxide carcinogenesis and chemical signaling, as well as medical diagnostics for inflammation.
In vivo detection
Single-molecule level detection
New cellular assays for the study of
nitric oxide carcinogenesis and chemical signaling
tool for medical diagnostics
Implantable platform for in vivo sensing