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oe1(光电查) - 科学论文

65 条数据
?? 中文(中国)
  • Ultrafast synthesis of gold nanosphere cluster coated by graphene quantum dot for active targeting PA/CT imaging and near-infrared laser/pH-triggered chemo-photothermal synergistic tumor therapy

    摘要: In this work, simple raw materials and reaction conditions were used to synthesize a versatile nanoprobe using a one-step method. Graphene quantum dot (GQD) and gold chloride were mixed and irradiated with ultra-violet (UV) radiation for 1 min. Then, the gold nanosphere cluster with the diameter of 50 nm and coated using GQD was formed using a facile one-step approach. GQD played the roles of reducing agent, stabilizer and drug carrier instead of a harmful reducing agent or stabilizer. The nanoprobe had good dispersion, stability, excellent photoacoustic imaging (PAI) and computed tomography (CT) imaging performance, low cytotoxicity and photothermal conversion e?ciency of up to 51.31%. The results for cell and animal experiments showed that targeted PAI/CT imaging of tumor after modi?cation of folic acid (FA) could be obtained using the probe. Meanwhile, after the adsorption of doxorubicin, the chemo-photothermal combined therapy for tumor could be carried out through controlled drug release from GQD under heated and acidic environment of tumor. Additionally, the treatment e?ect was signi?cantly superior to single modes. The body weight, Hematoxylin and Eeosin (H&E) staining of main organs and blood biochemical indicators showed that the probe had good biological safety after injection. The current work proposes a new dual-mode bio-imaging and chemo-photothermal combined therapy nanoprobe, which presents good application prospect for tumor theragnostic.

    关键词: CT imaging,One-step synthesis,Drug release,Photoacoustic imaging,Chemo-photothermal therapy

    更新于2025-11-25 10:30:42

  • Polydopamine-functionalized black phosphorus quantum dots for cancer theranostics

    摘要: Black phosphorus (BP) is a promising theranostic agent owing to its excellent photothermal property, biocompatibility and biodegradability. However, the rapid degradation of BP with oxygen and moisture causes the innate instability that is the Achilles’ heel of BP, hindering its further applications in cancer theranostics. Herein, a facile surface passivation strategy was developed to prepare polydopamine (PDA) coated BP quantum dots (QDs) (denoted as BP@PDA) through self-polymerization method. PDA with enriched phenol groups plays as a scavenger of reactive oxygen, which can efficiently prevent the oxidation of BP quantum dots and make them much stable in water (~90% for BP@PDA vs. only 10% for pure BP QDs after 10 days storage). Furthermore, PDA with strong near-infrared (NIR) absorption could greatly improve the photothermal conversion efficiency (PCE) of BP QDs from 22.6% to 64.2% (~2.84-fold higher). Considering the excellent biodegradability and good biocompability of both BP QDs and PDA, the as-prepared BP@PDA hold great potential for cancer theranostics.

    关键词: Photoacoustic imaging,Black phosphorus,Photothermal therapy,Cancer theranostics,Polydopamine

    更新于2025-11-19 16:56:42

  • <p>A multifunctional-targeted nanoagent for dual-mode image-guided therapeutic effects on ovarian cancer cells</p>

    摘要: Nanomedicine has emerged as a novel therapeutic modality for cancer treatment and diagnosis. Lipid–polymer hybrid nanoparticles (LPHNPs) are core–shell nanoparticle (NP) structures comprising polymer cores and lipid shells, which exhibit complementary characteristics of both polymeric NPs and liposomes. However, it is difficult to wrap perfluoropentane (PFP) into core–shell NPs in the existing preparation process, which limits its application in the integration of diagnosis and treatment. Methods: The folate-targeted LPHNPs-loaded indocyanine green/PFP-carrying oxygen (TOI_HNPs) using a combination of two-step method and solution evaporation technique for the first time. The essential properties and dual-mode imaging characteristics of developed NPs were determined. The cellular uptake of TOI_HNPs was detected by confocal microscopy and flow cytometry. The SKOV3 cell viability and apoptosis rate were evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay and flow cytometry. The ROS was demonstrated by fluorescence microplate reader and the expression of hypoxia-inducible factor 1-alpha (HIF-1α) and IL-6 was detected by Western blot. Results: TOI_HNPs showed spherical morphology with particle size about (166.83±5.54) nm and zeta potential at -(30.57±1.36) mV. It exhibited better stability than lipid NPs and higher encapsulation efficiency as well as active targeting ability than poly (lactic-co-glycolic acid) (PLGA) NPs. In addition, the novel NPs could also act as the contrast agents for ultrasound and photoacoustic imaging, providing precision guidance and monitoring. Furthermore, TOI_HNPs-mediated photo–sonodynamic therapy (PSDT) caused more serious cell damage and more obvious cell apoptosis, compared with other groups. The PSDT mediated by TOI_HNPs induced generation of intracellular ROS and downregulated the expression of HIF-1α and IL-6 in SKOV3 cells. Conclusion: This kind of multifunctional-targeted nanoagent may provide an ideal strategy for combination of high therapeutic efficacy and dual-mode imaging guidance.

    关键词: core-shell nanoparticle,ultrasound,photo-sonodynamic therapy,phase transformation,photoacoustic imaging,laser

    更新于2025-11-14 17:03:37

  • Photoacoustic temperature imaging based on multi-wavelength excitation

    摘要: Building further upon the high spatial resolution offered by ultrasonic imaging and the high optical contrast yielded by laser excitation of photoacoustic imaging, and exploiting the temperature dependence of photoacoustic signal amplitudes, this paper addresses the question whether the rich information given by multispectral optoacoustic tomography (MSOT) allows to obtain 3D temperature images. Numerical simulations and experimental results are reported on agarose phantoms containing gold nanoparticles and the effects of shadowing, reconstruction flaws, etc. on the accuracy are determined.

    关键词: photoacoustic imaging,absorption coefficient,finite difference,multispectral optoacoustic tomography

    更新于2025-11-14 15:30:11

  • Carbon Nanomaterials for Bioimaging, Bioanalysis, and Therapy || Photoacoustic Imaging with Carbon Nanomaterials

    摘要: Photoacoustic imaging is a novel, noninvasive biomedical imaging modality that has evolved considerably over the last few decades. As a label‐free imaging modality using both endogenous and exogenous contrast agent it has shown many advantages to safely and effectively differentiate diseased tissue from healthy tissues at a deeper depth. While endogenous light‐absorbing objects in living subjects such as hemoglobin, melanin, and glucose, have been useful in imaging, the use of exogenous contrast agents can improve the detection sensitivity and specific tissue‐targeting capabilities of photoacoustic imaging modality further. The carbon nanomaterial has been found to be one of the best contrast agents for photoacoustic imaging, which has strong absorption properties and great biocompatibility. This chapter covers the basic introduction of photoacoustic imaging and the application of carbon nanomaterials contrast agent such as imaging‐guided therapy and multimodal imaging in photoacoustic imaging.

    关键词: photoacoustic imaging,contrast agents,photothermal therapy,photodynamic therapy,multimodal imaging,biomedical imaging,carbon nanomaterials

    更新于2025-09-23 15:22:29

  • Ordered assemblies of Fe3O4 and a donor-acceptor-type π-conjugated polymer in nanoparticles for enhanced photoacoustic and magnetic effects

    摘要: We report that the ordered structure in the assemblies of iron oxide nanoparticles in conjugated polymer nanoparticles is the key to achieve better properties to realize multimodal theranostic agents for magnetic resonance and photoacoustic imaging. Hybrid nanoparticles of a conjugated polymer (PCPDTBT), a phospholipid (D8PE) with a primary amine polar head, and iron oxide (Fe3O4) nanoparticles were prepared by a phase-separated film shattering process by varying the iron oxide concentration while maintaining a fixed mixing ratio of PCPDTBT and D8PE. Notably, the hybrid nanoparticles assembled at a molar mixing ratio of 1:1:0.8 (PCPDTBT/D8PE/Fe3O4) exhibited the shortest transversal relaxation time, T2, and a photoacoustic signal 22 times higher than that obtained at the 1:1:0 mixing ratio. Structural analysis by X-ray diffraction together with the measurements of energy transfer by transient absorption spectroscopy confirmed that the structural ordering of these hybrid nanoparticles was responsible for their enhanced photoacoustic and magnetic properties.

    关键词: Conjugated polymers,Photoacoustic imaging,Magnetic resonance imaging,Iron oxides,Hybrid nanoparticles

    更新于2025-09-23 15:22:29

  • Stimuli-Responsive Nanotheranostics for Real-Time Monitoring Drug Release by Photoacoustic Imaging

    摘要: Molecular photoacoustic imaging (PA) is a promising technology to understand tumor pathology and guide precision therapeutics. Despite the capability of activatable PA probes to image tumor-specific biomarkers, limitations in their molecular structure hamper them from effective drug delivery and the drug release monitoring. Herein, we developed a perylene diimide (PDI) based theranostic platform that provides noninvasive PA imaging signals to monitor tumor-specific pH-responsive drug release. Methods: we first designed and synthesized an acid-responsive amine-substituted PDI derivative. The pH sensitive properties of the PDI was demonstrated by density functional theory (DFT) calculations, UV-vis experiments and PA studies. The theranostic platform (THPDINs) was fabricated by self-assembly of the acid-responsive PDI, a pH irrelevant IR825 dye, and anti-cancer drug doxorubicin (DOX). The PA properties in various pH environment, drug delivery, cytotoxicity, cell uptake, ratiometric PA imaging and anti-tumor efficacy of the THPDINs were investigated in vitro and in vivo by using U87MG glioma cell line and U87MG tumor model. Results: We found that our designed PDI was sensitive to the tumor specific pH environment, reflected by absorbance shift, PA intensity and aggregation morphology changes in aqueous solution. The as-synthesized pH sensitive PDI acted as a molecular switch in the THPDINs, in which the switch can be triggered in the mild acidic tumor microenvironment to accelerate DOX release. Meanwhile, the DOX release could be monitored by ratiometric PA imaging. Conclusions: We developed a multifunctional PDI based theranostic platform for noninvasive real-time ratiometric PA imaging of tumor acidic pH and monitoring of drug release in living mice simultaneously. This strategy will shed light on the development of smart activatable theranostic nanoplatforms and will significantly advance the application of PA theranostics in biology and medicine.

    关键词: photoacoustic imaging,drug delivery,pH-responsive,ratiometric imaging,theranostics

    更新于2025-09-23 15:22:29

  • In Vivo Chemoselective Photoacoustic Imaging of Copper(II) in Plant and Animal Subjects

    摘要: The detection of Cu2+ in living plants and animals is of great importance for environment monitoring and disease diagnosis. Here, a near-infrared (NIR) turn-on photoacoustic (PA) probe (denoted as LET-2) is developed for Cu2+ detection in living subjects, such as soybean sprouts and mice. The absorbance band of LET-2 shifts from 625 to 715 nm after the interaction with Cu2+, thus producing strong PA signal output at 715 nm (PA715) as an indicator. The PA715 value is increased as a function of the concentration of Cu2+ (0 × 10?6–20 × 10?6 m), with a calculated limit of detection of 10.8 × 10?9 m. More importantly, both in vitro and in vivo studies in soybean sprouts and mice indicate that the as-prepared LET-2 PA probe is highly sensitive and selective for Cu2+ detection. These findings provide a solution for in vivo detection of metal ions by using chemoselective PA probes.

    关键词: animals,photoacoustic imaging,copper detection,in vivo,plants

    更新于2025-09-23 15:22:29

  • Quantitative photoacoustic imaging study of tumours in vivo: Baseline variations in quantitative measurements

    摘要: Photoacoustic imaging (PAI) provides information on haemoglobin levels and blood oxygenation (sO2). To facilitate assessment of the variability in sO2 and haemoglobin in tumours, for example in response to therapies, the baseline variability of these parameters was evaluated in subcutaneous head and neck tumours in mice, using a PAI system (MSOTinVision-256TF). Tumours of anaesthetized animals (midazolam-fentanyl-medetomidine) were imaged for 75 min, in varying positions, and repeatedly over 6 days. An increasing linear trend for average tumoural haemoglobin and blood sO2 was observed, when imaging over 75 min. There were no significant differences in these temporal trends, when repositioning tumours. A negative correlation was found between the percent decrease in blood sO2 over 6 days and tumour growth rate. This paper shows the potential of PAI to provide baseline data for assessing the significance of intra- and inter-tumoural variations that may eventually have value for predicting and/or monitoring cancer treatment response.

    关键词: Head and neck subcutaneous tumours,Hemoglobin,Pimonidazole,Blood sO2,Hypoxia,Photoacoustic imaging

    更新于2025-09-23 15:22:29

  • Monitoring neovascularization and integration of decellularized human scaffolds using photoacoustic imaging

    摘要: Tissue engineering is a branch of regenerative medicine that aims to manipulate cells and scaffolds to create bioartificial tissues and organs for patients. A major challenge lies in monitoring the blood supply to the new tissue following transplantation: the integration and neovascularization of scaffolds in vivo is critical to their functionality. Photoacoustic imaging (PAI) is a laser-generated ultrasound-based technique that is particularly well suited to visualising the microvasculature due to the high optical absorption of haemoglobin. Here, we describe an early proof-of-concept study in which PAI in widefield tomography mode is used to image biological, decellularized human tracheal scaffolds. We found that photoacoustic imaging allowed the longitudinal tracking of scaffold integration into subcutaneous murine tissue with high spatial resolution at depth over an extended period of time. The results of the study were consistent with post-imaging histological analyses, demonstrating that photoacoustic imaging can be used to non-invasively monitor the extent of vascularization in biological tissue-engineered scaffolds. We anticipate that this technique could find application in tissue-engineering studies aimed at improving the speed and extent of scaffold neovascularization. With technological development, it could also be used to inform the clinical timing of surgical procedures following heterotopic transplantation to establish vasculature.

    关键词: vascularization,angiogenesis,photoacoustic imaging,transplantation,tissue engineering,trachea

    更新于2025-09-23 15:22:29