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Yang Li, Huabing Zhang, Yilin Chen, Jinyuan Ma, Jinyan Lin, Yinying Zhang, Zhongxiong Fan, Guanghao Su, Liya Xie, Xuan Zhu, Zhenqing Hou
Combinational cancer therapy has been considered as a promising strategy to achieve synergetic therapeutic effects and suppression of multidrug resistance. Herein, we adopted a combination of methotrexate (MTX), an antimetabolite acting on cytoplasm, and 10-hydroxycamptothecin (HCPT), an alkaloid acting on nuclei, to treat cancer. Given the different solubilities, membrane permeabilities, and anticancer mechanisms of both drugs, we developed a dual-targeting delivery system based on 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-hyaluronic acid (a principal ligand of CD44 receptors)-MTX (a selective ligand of folate receptors) nanoparticles, which was exploited to carry HCPT-MTX conjugate for synergistically boosting dual-drug co-delivery...
May 22, 2018: Biomaterials Science
Jinyoung Kang, Dokyoung Kim, Junxin Wang, Yunho Han, Jonathan M Zuidema, Ali Hariri, Ji-Ho Park, Jesse V Jokerst, Michael J Sailor
Photoacoustic (PA) imaging allows visualization of the physiology and pathology of tissues with good spatial resolution and relatively deep tissue penetration. The method converts near-infrared (NIR) laser excitation into thermal expansion, generating pressure transients that are detected with an acoustic transducer. Here, we find that the response of the PA contrast agent indocyanine green (ICG) can be enhanced 17-fold when it is sealed within a rigid nanoparticle. ICG encapsulated in particles composed of porous silicon (pSiNP), porous silica, or calcium silicate all show greater PA contrast relative to equivalent quantities of free ICG, with the pSiNPs showing the strongest enhancement...
May 21, 2018: Advanced Materials
Mei Chen, Zhide Guo, Qinghua Chen, Jingping Wei, Jingchao Li, Changrong Shi, Duo Xu, Dawang Zhou, Xianzhong Zhang, Nanfeng Zheng
Radiolabeled nanoparticles (NPs), taking advantage of nanotechnology and nuclear medicine, have shown attractive potential for cancer diagnosis and therapy. However, the high background signal in the liver and long-term toxic effects of radioisotopes caused by the nonselective accumulation of radiolabeled nanoparticles in organs have become the major challenges. Here, we report a pH-sensitive multifunctional theranostic platform with radiolabeled Pd nanosheets through a simple mixture of ultra-small Pd nanosheets and radioisotopes utilizing the strong adsorption of 131 I and 125 I on their surfaces (denoted as 131 I-Pd-PEG or 125 I-Pd-PEG)...
May 14, 2018: Chemical Science
Paolo Armanetti, Salvador Pocoví-Martínez, Alessandra Flori, Cinzia Avigo, Domenico Cassano, Luca Menichetti, Valerio Voliani
Ultrasound (US) imaging is a well-established diagnostic technique to image soft tissues in real time, while photoacoustic (PA) is an emerging imaging technique employed to collect molecular information. Integration of PA and US imaging provides complementary information enhancing diagnostic accuracy without employing ionizing radiations. The development of contrast agents able to combine PA and US features is pivotal to improve the significance of PAUS imaging and for PAUS-guided treatment of neoplasms. Here, we demonstrate in relevant ex-vivo models that disassembling passion fruit-like nano-architectures (pfNAs) can be employed in PAUS imaging...
May 17, 2018: Nanomedicine: Nanotechnology, Biology, and Medicine
Thomas Kirchner, Janek Gröhl, Lena Maier-Hein
Real-time monitoring of functional tissue parameters, such as local blood oxygenation, based on optical imaging could provide groundbreaking advances in the diagnosis and interventional therapy of various diseases. Although photoacoustic (PA) imaging is a modality with great potential to measure optical absorption deep inside tissue, quantification of the measurements remains a major challenge. We introduce the first machine learning-based approach to quantitative PA imaging (qPAI), which relies on learning the fluence in a voxel to deduce the corresponding optical absorption...
May 2018: Journal of Biomedical Optics
Duyang Gao, Yubin Liu, Yating Wang, Zhen Yuan
Background: Construction of nanoprobes for dual-modal fluorescence/photoacoustic imaging (PAI) is of great importance for the detection of disease pathology and the development of innovative therapeutics. Previously ultra-small gold clusters were designed and used as contrast agents for fluorescence imaging (FLI). However, it is not clear whether they can also serve as promising probes for PAI. In this study, protein-modified ultra-small gold clusters are produced and examined quantitatively as enhanced contrast agents for dual-modal in vivo fluorescence and PAI...
April 2018: Quantitative Imaging in Medicine and Surgery
Mengmeng Sun, Jianwen Guo, Hanjun Hao, Tong Tong, Kun Wang, Weiping Gao
Near-infrared (NIR)-absorbing conjugated polymer nanoparticles are interesting for imaging-guided combination therapy, especially for synergistic photothermal therapy and chemotherapy; however, most of them target tumours passively through the enhanced permeability and retention (EPR) effect, leading to low utilization efficiency. To address this problem, we report an active tumour-targeting strategy of tumour-homing chimeric polypeptide-conjugated NIR-absorbing conjugated-polymer nanoparticles as a new class of drug nanocarriers for imaging-guided combination therapy of cancer...
2018: Theranostics
Xiaoxiang Gao, Chao Tao, Rong Zhu, Xiaojun Liu
In this work, photoacoustic eigen-spectrum analysis was proposed for noninvasively characterizing the mechanical properties of materials. We theoretically predicted the relationship between the photoacoustic eigen-spectra of cylindrical optical absorbers and their mechanical properties. Experimental measurements of eigen-spectra extracted from photoacoustic coda waves agreed well with the theoretical predictions. We then applied the photoacoustic eigen-spectrum analysis for contactless monitoring of low-cycle fatigue damage...
May 17, 2018: Scientific Reports
Marcel Niehaus, Jens Soltwisch
Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is widely used for the analysis of large biomolecules in numerous applications. The technique utilizes nanosecond-long laser pulses at various spot sizes to eject and ionize large molecules embedded in a highly absorptive chemical matrix. Despite the methods name, 'molecular desorption' from the matrix crystal surface is not the sole mechanism discussed for material ejection in MALDI, but additional ablation of larger clusters has been reported...
May 17, 2018: Scientific Reports
Zhenhui Zhang, Yujiao Shi, Sihua Yang, Da Xing
We have developed a second harmonic photoacoustic microscopy (SH-PAM) for subdiffraction-limited imaging based on nonlinear thermal diffusion. When a sine-modulated Gaussian temperature field is introduced by a laser beam, the temperature dependence of the thermal diffusivity induces a nonlinear photoacoustic (PA) effect and thus results in the production of second harmonic PA signals. We demonstrate through both simulation and experiment that the second harmonic PA images can be reconstructed with a lateral resolution exceeding that of conventional optical resolution PA microscopy...
May 15, 2018: Optics Letters
David M Egolf, Ryan K W Chee, Roger J Zemp
Delay-and-sum beamforming (DSB) of photoacoustic data does not incorporate a priori spatial sparsity of the imaging target. By incorporating this information into beamforming for limited-view photoacoustic computed tomography, we experimentally obtained enhanced resolution images of wires at a depth of 8.5 mm in a tissue mimicking scattering medium. Using a 21 MHz transducer, we improved the resolution from the 200 to 250 μm achieved by DSB to 75 μm. The sparsity-based technique also generated a cleaner image with a background signal level of roughly -50  dB, much lower than the roughly -18  dB background signal level of DSB...
May 15, 2018: Optics Letters
Yannick Saalberg, Marcus Wolff
We applied a multivariate analysis (MVA) to spectroscopic data of gas mixtures in the mid-IR in order to calculate the concentrations of the single components which exhibit strongly overlapping absorption spectra. This is a common challenge in broadband spectroscopy. Photoacoustic (PA) measurements of different volatile organic compounds (VOCs) in the wavelength region of 3250 nm to 3550 nm served as the exemplary detection technique. Partial least squares regression (PLS) was used to calculate concentrations from the PA spectra...
May 15, 2018: Sensors
Wei Qin, Qian Chen, Lei Xi
The combination of optical resolution photoacoustic microscopy (ORPAM) and optical coherence tomography (OCT) is capable of providing complementary imaging contrasts. Unfortunately, the miniaturization of ORPAM remains a major challenge in the development of a handheld dual-modality imaging microscope with OCT. Here, we report the design and evaluation of an integrated ORPAM and OCT imaging probe using a two-dimensional MEMS (micro-electro-mechanical-system)-based optical scanner. This microscope, weighting 35...
May 1, 2018: Biomedical Optics Express
Josefine Liljeruhm, Saskia K Funk, Sandra Tietscher, Anders D Edlund, Sabri Jamal, Pikkei Wistrand-Yuen, Karl Dyrhage, Arvid Gynnå, Katarina Ivermark, Jessica Lövgren, Viktor Törnblom, Anders Virtanen, Erik R Lundin, Erik Wistrand-Yuen, Anthony C Forster
Background: Coral reefs are colored by eukaryotic chromoproteins (CPs) that are homologous to green fluorescent protein. CPs differ from fluorescent proteins (FPs) by intensely absorbing visible light to give strong colors in ambient light. This endows CPs with certain advantages over FPs, such as instrument-free detection uncomplicated by ultra-violet light damage or background fluorescence, efficient Förster resonance energy transfer (FRET) quenching, and photoacoustic imaging. Thus, CPs have found utility as genetic markers and in teaching, and are attractive for potential cell biosensor applications in the field...
2018: Journal of Biological Engineering
Meirong Hou, Chenggong Yan, Zelong Chen, Qingliang Zhao, Miaomiao Yuan, Yikai Xu, Bingxia Zhao
Ternary copper-based chalcogenide nanomaterials have become rather attractive due to the near-infrared (NIR) response in cancer theranostic fields. However, it is still challenging to further improve the theranostic efficiency of these nanomaterials. Herein, Cu-Sb-S nanoparticles (NPs) around 24 nm are synthesized facilely and functionalized with poly(vinylpyrrolidone) (PVP). Under the NIR irradiation, the resultant PVP-Cu-Sb-S NPs exhibit a relatively high photothermal conversion efficiency of 53.16% and a simultaneous reactive oxygen species (ROS) generation effect...
May 9, 2018: Acta Biomaterialia
Kara Harmatys, Juan Chen, Danielle Charron, Christina MacLaughlin, Gang Zheng
Biomimetics are reconstructions of natural systems in engineered forms to exploit their structural or functional properties. Current biomimetics for medical applications use a single biomimetic approach to imitate natural structures, which can be insufficient for reconstructing structurally complex natural systems. Multi-pronged efforts may resolve these complexities. To achieve interesting nanostructure-driven optical properties, we engineered a dual-biomimetic system contained within a single nanoagent to recapitulate the efficient light-harvesting organelles, chlorosomes, which have unique dye assemblies and tunable photonic properties...
May 11, 2018: Angewandte Chemie
Ji Qi, Chao Chen, Xiaoyan Zhang, Xianglong Hu, Shenglu Ji, Ryan T K Kwok, Jacky W Y Lam, Dan Ding, Ben Zhong Tang
Fluorescence and photoacoustic imaging have different advantages in cancer diagnosis; however, combining effects in one agent normally requires a trade-off as the mechanisms interfere. Here, based on rational molecular design, we introduce a smart organic nanoparticle whose absorbed excitation energy can be photo-switched to the pathway of thermal deactivation for photoacoustic imaging, or to allow opposed routes for fluorescence imaging and photodynamic therapy. The molecule is made of a dithienylethene (DTE) core with two surrounding 2-(1-(4-(1,2,2-triphenylvinyl)phenyl)ethylidene)malononitrile (TPECM) units (DTE-TPECM)...
May 10, 2018: Nature Communications
Qingyan Jia, Xiuli Zheng, Jiechao Ge, Weimin Liu, Haohui Ren, Shiqing Chen, Yongmei Wen, Hongyan Zhang, Jiasheng Wu, Pengfei Wang
As phototheranostic agents, carbon dots (CDs), have recently drawn considerable attention due to their excellent physicochemical properties. However, the complex synthetic route and high-cost of CDs greatly limit their practical application. To address this issue, given their nearly infinite supply from nature, Hypocrella bambusae is used as the precursor for the preparation of CDs in this study. The obtained Hypocrella bambusae CDs (HBCDs) possess good water solubility, broad absorption (350-800 nm), red-light emission (maximum peak at 610 nm), and low biotoxicity...
May 4, 2018: Journal of Colloid and Interface Science
Taeho Kim, Qiangzhe Zhang, Jin Li, Liangfang Zhang, Jesse V Jokerst
Ag+ ions are a well-known antibacterial agent, and Ag nanoparticles act as a reservoir of these Ag+ ions for targeted therapy of bacterial infections. However, there are no tools to effectively trigger and monitor the release of Ag+ ions from Ag nanoparticles. Photoacoustic (PA) imaging is an emerging noninvasive imaging tool, and gold nanorods (AuNRs) are an excellent contrast agent for PA imaging. In this work, we developed Au/Ag hybrid nanoparticles by coating AuNRs with silver (Ag), which decreased their photoacoustic signal...
May 10, 2018: ACS Nano
Yushen Jin, Xin Yang, Jie Tian
Early identification and treatment of hepatocellular carcinoma is very important for improving the prognosis and survival rate of the patient. To enhance the visualization and treatment efficiency of HCC, a theranostic agent has been developed that combines photoacoustic/fluorescence imaging with photothermal therapy for cancer. We report the synthesis of multifunctional theranostic SP94-modified polypyrrole (PPy)-BSA-ICG nanoparticles by a simple method. The multifunctional theranostic agent helped to combine two modes of imaging modalities, i...
May 10, 2018: Nanoscale
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