Biocompatible NIR-silica Nanoparticles With Strong Brightness For Lymphoma Imaging

Optical imaging as a promising molecular imaging approach is widely used in brain function imaging, drug deliver, tumor targeting, photo thermal therapy, imaging-guided surgery and lymph nodes mapping. As one of the most important tools in optical imaging technique, the fluorescent probes and labels are developed fast recent years.Myriad inorganic and organic near infrared(NIR) fluorescence, loaded into some nanostructures as NIR contrast agents for animal in vivo optical imaging, which have been investigated in recent years due to their negligible absorption and auto-fluorescence in this NIR window. However, it can be limited in its effectiveness due to low stability and fast photo-bleaching, although they have excellent quantum yield and low toxicity.The biocompatible near infrared silica nanoparticles(NIR-silica NPs) with strong brightness for Lymphoma imaging to achieve a higher signal-to-noise ratio and short the exposure time can speed up the signal detection. The size of the NIR-silica NPs was around 50 nm, which provides higher cellular uptake efficiency. We incorporated the IR-780 dye into the NIR-silica NPs to achieve a highly efficient fluorescent contrast agent with good solubility and metabolic stability for in vitro and in vivo Lymphoma imaging.In the long term imaging study, the tumor targeting imaging was performed through the construction of the Lymphoma-bearing nude mice model. The NIR-silica NPs with inherent size passive targeted the tumor by enhanced permeability and retention(EPR) effect. The detectable fluorescent signal, remained in the tumor, could last at least 10 days, which may cause by that NIR-silica NPs prevent the dye from the degradation and shows the strong capability of long circulation time for long term in vivo Lymphoma imaging.