Nanomaterials For Multimodal Bioimaging And Its Application

Nanotechnology gets popularity in recent years.Nanomaterials are widely used in our daily life and play a key role in the field of materials science,energy resources,food additives and medical technologies.Especially,in biomedical realm,the newly synthesized nanomaterials are utilized in drug delivery system,diagnosis and therapy of various diseases including cancer,cardiovascular and cerebrovascular diseases.In this contribution chloroauric acid?HAuCl4?and ferrous ions?FeCl2?are innovatively used to in situ biosynthesize the Au-Fe nanocomposites within tumor by utilizing the unique neoplastic microenvironment.The MTT assay method is used to evaluate the cytotoxicity of the materials,whereas in vivo bioimaging,blood-serum biomarkers and histological sections are used to find adverse effects of in situ biosynthesized materials on circulatory and excretory system.All results demonstrate Au-Fe nanocomposite with excellent biocompatibility with almost no adverse effects to vital organs.The biosynthesized Au NCs can be used as nano probe for fluorescence and CT imaging,whereas Fe NCs can significantly enhance the MR signal.The synergistic effect of both?Au-Fe NCs?can achieve the early multimodal bioimaging of tumor and raise the possibility of nanoprobes in vivo biosynthesis for multimodal bioimaging to early diagnose the deep seated tumors.Similarly,the zinc gluconate has excellent biocompatibility and was used as precursor for nanoprobes biosynthesized to detect the cerebral ischemic stroke.It is found that zinc ions can pass through the blood-brain barrier and accumulate in the ischemic hypoxic inflammatory lesions,and then in situ biosynthesis zinc nanoclusters for fluorescence bioimaging.The relavant detection method is simple and effective,which can be used for early diagnosis and rapid bioimaging of cerebral ischcmic stroke.Furthermore,we also utilize the TiO₂ nanowhiskers potential as delivery vehicle that adsorbe TSPP?Tetra Sulphonatophenyl porphyrin?and deliver it to the target tissue without any toxic effects.The protection and controlled release of TSPP by TiO₂ nanowhiskers is demonstrated by both in vitro and in vivo findings.Based on these observations,a new method for RA diagnosis and treatment is reported,which is comprised of TSPP and TiO₂ nanowhiskers as excellent biological probe and photodynamic therapy reagent.It is found that TSPP-TiO₂ nanocomposite based PDT can significantly reduce the level IL-17 and TNF-?,and affect other blood parameters associated to inflammation,which ultimately lead to alleviation of RA symptoms.Meanwhile,the TSPP-TiO₂ nanocomposite with good fluorescence properties can also realize the early detection and diagnosis through fluorescence bioimaging of CIA model before the onset of clinical signs.In addition,after the photoactivation of TSPP-TiO₂ nanocomposite in vivo,we found changes in miRNA levels of RA infected joints isolated BMSC.The results show that the expression level of rno-mir-375-3p and rno-mir-196-3p is upregulated more than 100 times when compared with control group;meanwhile,miRNAs which are closely associated with RA pathogenesis,are also found to have significant upregulation.In addition to theranostics affect,this study can help us to understand the role of BMSC in the pathogenesis of RA.Moreover,for the first time the miRNA expression in BMSC was exploited after photoactivation of TSPP-TiO₂ in RA murine models...