Multifunctional nanocomposites have the potential to integrate sensing, diagnostic, and therapeutic functions into a single nanostructure. Herein, we synthesize Fe 3 O 4 @polydopamine core-shell nanocomposites (Fe 3 O 4 @PDA NCs) through an in situ self-polymerization method. Dopamine, a melanin-like mimic of mussel adhesive proteins, can self-polymerize to form surface-adherent polydopamine (PDA) films onto a wide range of materials including Fe 3 O 4 nanoparticles used here. In such nanocomposites, PDA provides a number of advantages, such as near-infrared absorption, high fluorescence quenching efficiency, and a surface for further functionalization with biomolecules. We demonstrate the ability of the Fe 3 O 4 @PDA NCs to act as theranostic agents for intracellular mRNA detection and multimodal imaging-guided photothermal * Address correspondence to hhyang@fio.org.cn, gangliu.cmitm@xmu.edu.cn.. Conflict of Interest:The authors declare no competing financial interest. Supporting Information Available:Additional information as noted in the text. This material is available free of charge via the Internet at http://pubs.acs.org. Messenger RNA (mRNA), a single-stranded ribonucleic acid, is also the blueprint for the cellular production of proteins. Moreover, some mRNAs are disease-relevant and can be utilized as markers to determine the stage of the disease. 22 Recently, several methods such as microarray analysis 23 and real-time polymerase chain reaction (RT-PCR) 24 have been developed for mRNA detection. Although these methods are effective for detecting mRNA expression in bulk samples, they are incapable of identifying cell-to-cell mutations. Significantly, many important biological processes not only are related with bulk mRNA expression, but also rely highly on cell-to-cell variations in mRNA. 25 Thus, it is necessary to develop useful approaches for detecting mRNA in living cells. [26][27][28][29][30][31][32] In this work, we fabricated multifunctional Figure 1a). Furthermore, we demonstrated that PDA can adsorb dye-labeled singlestranded DNA (ssDNA) probe and effectively quench the fluorescence of the dye. In the presence of the target, the specific binding between the dye-labeled ssDNA probe and its Figure 1c). Our results suggest a high potential for the use of PDA in the construction of multifunctional nanocomposites for simultaneous diagnosis and therapy of cancer. HHS Public Access RESULTS AND DISCUSSIONFe 3 O 4 NPs were easily coated with a uniform PDA shell by dispersing them in an alkaline DA solution and mildly shaking at room temperature for 4 h. Transmission electron microscopy (TEM) revealed that approximately a 4 nm thick PDA shell was wrapped on the surface of the Fe 3 O 4 NPs after self-polymerization of the DA ( Figure 2a). The dynamic light scattering (DLS) data showed that the hydrodynamic diameter of the Fe 3 O 4 NPs was increased after the PDA coating (Supporting Information Figure S1), which is consistent with the TEM results. Moreover, the Fe 3 O 4 @PDA NCs exhibited excelle...

A new theranostic platform is developed based on biocompatible poly(acrylic acid) (PAA)‐Co9 Se8 nanoplates. These PAA‐Co9 Se8 nanoplates are successfully utilized for photoacoustic imaging (PAI)/magnetic resonance imaging (MRI) dual‐modal imaging. Moreover, the PAA‐Co9 Se8‐DOX shows pH‐responsive chemotherapy and enables the combination of photothermal therapy and chemotherapy to receive superior antitumor efficacy. This work promises further exploration of 2D nanoplatforms for theranostic applications.

Novel luminescent "nano-bombs" based on a self-assembled system of carbon-nanodots, termed supra-CDs, are developed. The luminescence of these luminescent "nano-bombs" depends strongly on water contact; they show weak emission in toluene and decompose in contact with water, resulting in strong photoluminescence. Paper coated with these "nano-bombs" is successfully applied for water-jet printing of luminescence patterns and the mapping of human sweat-pore patterns.

A construction strategy for ratiometric fluorescent nanosensors based on water soluble C-dots was developed, which could sense temperature (10-82 °C), pH values (lower than 6.0 or higher than 8.6) and Fe(3+) ions (>0.04 μM) by monitoring the intensity ratios of dual fluorescence bands (Ib/Ig) under 380 nm excitation. Ib/Ig decreased nearly linearly with increasing temperature from 10 to 82 °C. In the pH range from 8.6 to 6.0, the Ib/Ig was nearly constant at 0.75. Ib/Ig gradually decreased from 0.75 to 0.52 in the pH range from 6.0 to 1.9, and increased nearly linearly from 0.52 to 0.75 in the pH range from 1.9 to 1.0. The dual fluorescence behavior was reversible in the pH range from 1.0 to 8.6. As pH increased from 10.6 to 13.0, the green fluorescence band decreased continuously and blue shifted with a nearly linear increase in Ib/Ig from 0.75 to 2.15, while the green fluorescence band cannot be recovered by decreasing the pH value. Ib/Ig was ultrasensitive and selective in presence of Fe(3+) (>0.04 μM) in neutral aqueous environments. The two fluorescence bands of the C-dots were attributed to different surface states that may produce different fluorescent signal responses to external physical or chemical stimuli.

We propose a novel method for object reconstruction of ghost imaging based on Pseudo-Inverse, where the original objects are reconstructed by computing the pseudo-inverse of the matrix constituted by the row vectors of each speckle field. We conduct reconstructions for binary images and gray-scale images. With equal number of measurements, our method presents a satisfying performance on enhancing Peak Signal to Noise Ratio (PSNR) and reducing computing time. Being compared with the other existing methods, its PSNR distinctly exceeds that of the traditional Ghost Imaging (GI) and Differential Ghost Imaging (DGI). In comparison with the Compressive-sensing Ghost Imaging (CGI), the computing time is substantially shortened, and in regard to PSNR our method exceeds CGI on grayscale images and performs as well as CGI visually on binary images. The influence of both the detection noise and the accuracy of measurement matrix on PSNR are also presented.

Aims: This study aims to explore non-invasive imaging of atherosclerotic plaque through magnetic resonance imaging (MRI) and near-infrared fluorescence (NIRF) by using profilin-1 targeted magnetic iron oxide nanoparticles (PF1-Cy5.5-DMSA-Fe3O4-NPs, denoted as PC-NPs) as multimodality molecular imaging probe in murine model of atherosclerosis. Methods and Results: PC-NPs were constructed by conjugating polyclonal profilin-1 antibody and NHS-Cy5.5 fluorescent dye to the surface of DMSA-Fe3O4-nanoparticles via condensation reaction. Murine atherosclerosis model was induced in apoE-/- mice by high fat and cholesterol diet (HFD) for 16 weeks. The plaque areas in aortic artery were detected with Oil Red O staining. Immunofluorescent staining and Western blot analysis were applied respectively to investigate profilin-1 expression. CCK-8 assay and transwell migration experiment were performed to detect vascular smooth muscle cells (VSMCs) proliferation. In vivo MRI and NIRF imaging of atherosclerotic plaque were carried out before and 36 h after intravenous injection of PC-NPs. Oil Red O staining showed that the plaque area was significantly increased in HFD group (p<0.05). Immunofluorescence staining revealed that profilin-1 protein was highly abundant within plaque in HFD group and co-localized with α-smooth muscle actin. Profilin-1 siRNA intervention could inhibit VSMCs proliferation and migration elicited by ox-LDL (p<0.05). In vivo MRI and NIRF imaging revealed that PC-NPs accumulated in atherosclerotic plaque of carotid artery. There was a good correlation between the signals of MRI and ex vivo fluorescence intensities of NIRF imaging in animals with PC-NPs injection. Conclusion: PC-NPs is a promising dual modality imaging probe, which may improve molecular diagnosis of plaque characteristics and evaluation of pharmaceutical interventions for atherosclerosis.

The emergence of photoluminescent carbon-based nanomaterials offers great potential for a wide variety of biomedical applications such as fluorescence imaging and cellular labeling. This report illustrates a novel photonic carbon dot (Cdots) based nanocarrier by using low molecular weight amphiphilic PEI (Alkyl-PEI2k) for surface passivation. The resulting water-dispersible Alkyl-PEI2k-Cdot nanocarrier possesses good stability, monodispersity with narrow size distribution and fluorescence properties. In addition, Alkyl-PEI2k-Cdot nanocarrier has a markedly low toxicity and good gene transfection effect in vitro and in vivo. Considering its low cytotoxicity, high gene delivery efficiency and fluorescence performance, Alkyl-PEI2k-Cdots could serve as a novel imaging-trackable gene-delivery nanocarrier promising for gene therapy and optical molecular imaging.

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