Ag2S nano dots have already bee n dem onstrated as promisi ng n ear-i nfrared (NIR-II, 1.0-1.45 pm) emitting nan oprobes with low toxicity, high penetration and high resolution for in vivo imaging of, for example, tum...Ag2S nano dots have already bee n dem onstrated as promisi ng n ear-i nfrared (NIR-II, 1.0-1.45 pm) emitting nan oprobes with low toxicity, high penetration and high resolution for in vivo imaging of, for example, tumors and vasculature. In this work, we have systematically investigated the pote ntial applicati on of function alized Ag2S nano dots for accurate imaging of damaged myocardium tissues after a myocardial in farction in duced by either partial or global ischemia. Ag2S nano dots surface-function alized with the an giote nsin II peptide (ATI I) have show n over 10-fold enhanced binding efficiency to damaged tissues than non-specifically (PEG) functionalized Ag2S nanodots due to their interaction with the upregulated angiotensin II receptor type I (AT1R). It is demonstrated how the NIR-II images generated by ATII-functionalized Ag2S nanodots contain valuable information about the location and extension of damaged tissue in the myocardium allowing for a proper identification of the occluded artery as well as an in direct evaluati on of the damage level. The pote ntial applicati on of Ag2S nano dots in the n ear future for in vivo imaging of myocardial infarction was also corroborated by performing proof of concept whole body imaging experiments.展开更多
Optical coherence tomography （OCT） has gained considerable attention in interventional cardiovascular medicine and is currently used in clinical settings to assess atherosclerotic lesions and to optimize stent place...Optical coherence tomography （OCT） has gained considerable attention in interventional cardiovascular medicine and is currently used in clinical settings to assess atherosclerotic lesions and to optimize stent placement. Artery imaging at the cellular level constitutes the first step towards cardiovascular molecular imaging, which represents a major advance in the development of personalized noninvasive therapies. In this work we demonstrate that cardiovascular OCT can be used to detect individual cells suspended in biocompatible fluids. Importantly, the combination of this catheter-based clinical technique with gold nanoshells （GNSs） as intracellular contrast agents led to a substantial enhancement in the backscattered signal produced by individual cells. This cellular contrast enhancement was attributed to the large backscattering cross-section of GNSs at the OCT laser wavelength （1,300 nm）. A simple intensity analysis of OCT cross-sectional images of suspended cells makes it possible to identify the sub-population of living cells that successfully incorporated GNSs. The generalizability of this method was demonstrated using two different cell lines （HeLa and Jurkat cells）. This work provides novel insights into cardiovascular molecular imaging using specifically modified GNSs.展开更多
Novel approaches for high contrast, deep tissue, in vivo fluorescence biomedical imaging are based on infrared-emitting nanoparticles working in the so-called second biological window （1,000-1,400 nm）. This allows f...Novel approaches for high contrast, deep tissue, in vivo fluorescence biomedical imaging are based on infrared-emitting nanoparticles working in the so-called second biological window （1,000-1,400 nm）. This allows for the acquisition of high resolution, deep tissue images due to the partial transparency of tissues in this particular spectral range. In addition, the optical excitation with low energy （infrared） photons also leads to a drastic reduction in the contribution of autofluorescence to the in vivo image. Nevertheless, as is demonstrated here, working solely in this biological window does not ensure a complete removal of autofluorescence as the specimens diet shows a remarkable infrared fluorescence that extends up to 1,100 nm. In this work, we show how the 1,340 nm emission band of Nd3. ions embedded in SrF2 nanoparticles can be used to produce autofluorescence free, high contrast in vivo fluorescence images. It is also dem- onstrated that the complete removal of the food-related infrared autofluorescence is imperative for the development of reliable biodistribution studies.展开更多
文摘Ag2S nano dots have already bee n dem onstrated as promisi ng n ear-i nfrared (NIR-II, 1.0-1.45 pm) emitting nan oprobes with low toxicity, high penetration and high resolution for in vivo imaging of, for example, tumors and vasculature. In this work, we have systematically investigated the pote ntial applicati on of function alized Ag2S nano dots for accurate imaging of damaged myocardium tissues after a myocardial in farction in duced by either partial or global ischemia. Ag2S nano dots surface-function alized with the an giote nsin II peptide (ATI I) have show n over 10-fold enhanced binding efficiency to damaged tissues than non-specifically (PEG) functionalized Ag2S nanodots due to their interaction with the upregulated angiotensin II receptor type I (AT1R). It is demonstrated how the NIR-II images generated by ATII-functionalized Ag2S nanodots contain valuable information about the location and extension of damaged tissue in the myocardium allowing for a proper identification of the occluded artery as well as an in direct evaluati on of the damage level. The pote ntial applicati on of Ag2S nano dots in the n ear future for in vivo imaging of myocardial infarction was also corroborated by performing proof of concept whole body imaging experiments.
文摘Optical coherence tomography （OCT） has gained considerable attention in interventional cardiovascular medicine and is currently used in clinical settings to assess atherosclerotic lesions and to optimize stent placement. Artery imaging at the cellular level constitutes the first step towards cardiovascular molecular imaging, which represents a major advance in the development of personalized noninvasive therapies. In this work we demonstrate that cardiovascular OCT can be used to detect individual cells suspended in biocompatible fluids. Importantly, the combination of this catheter-based clinical technique with gold nanoshells （GNSs） as intracellular contrast agents led to a substantial enhancement in the backscattered signal produced by individual cells. This cellular contrast enhancement was attributed to the large backscattering cross-section of GNSs at the OCT laser wavelength （1,300 nm）. A simple intensity analysis of OCT cross-sectional images of suspended cells makes it possible to identify the sub-population of living cells that successfully incorporated GNSs. The generalizability of this method was demonstrated using two different cell lines （HeLa and Jurkat cells）. This work provides novel insights into cardiovascular molecular imaging using specifically modified GNSs.
文摘Novel approaches for high contrast, deep tissue, in vivo fluorescence biomedical imaging are based on infrared-emitting nanoparticles working in the so-called second biological window （1,000-1,400 nm）. This allows for the acquisition of high resolution, deep tissue images due to the partial transparency of tissues in this particular spectral range. In addition, the optical excitation with low energy （infrared） photons also leads to a drastic reduction in the contribution of autofluorescence to the in vivo image. Nevertheless, as is demonstrated here, working solely in this biological window does not ensure a complete removal of autofluorescence as the specimens diet shows a remarkable infrared fluorescence that extends up to 1,100 nm. In this work, we show how the 1,340 nm emission band of Nd3. ions embedded in SrF2 nanoparticles can be used to produce autofluorescence free, high contrast in vivo fluorescence images. It is also dem- onstrated that the complete removal of the food-related infrared autofluorescence is imperative for the development of reliable biodistribution studies.
