查找使用阿拉丁产品的科研文献

SPION@Cu2−xS nanoclusters for highly sensitive MRI and targeted photothermal therapy of hepatocellular carcinoma

Xiaolong Liu,Xinyi Lin,Ming Wu,Ruhui Lin,Buhong Li,Jingfeng Liu

Considerable efforts have been made to incorporate both diagnostic and therapeutic functions into a single nanoplatform for biomedical applications. Herein, we report the synthesis and characterization of magnetite-loaded polymeric micelles (referred as SCDP-LA) for targeted magnetic resonance imaging (MRI) and photothermal therapy of hepatocellular carcinoma (HCC), by using an amphiphilic biocompatible polymer of lactobionic acid-modified 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (DSPE-PEG-LA) for the micelle formation. A cluster of SPION@Cu2−xS is densely encapsulated inside the hydrophobic core of the micelles, which offers both highly sensitive MRI and an excellent photothermal effect. The LA-modified PEG outlayer makes this micelle stable in aqueous solution. Due to the targeting ligand of LA, the SCDP-LA clusters could be selectively internalized into the hepatocellular cell line (HepG2 cells) but not into HeLa cells. In addition, the targeted ability of the SCDP-LA aqueous solution was further confirmed by enhanced MRI with a shorter T2 relaxation time in HepG2 cells. Meanwhile, it also demonstrates excellent performance to produce significantly enhanced local photothermal killing efficiency against HepG2 cells under NIR laser irradiation. In summary, the present multifunctional nanoplatform based on SPION@Cu2−xS nanoclusters will be a promising theranostic platform for targeted MRI-guided photothermal therapy.

Exploring a new SPION-based MRI contrast agent with excellent water-dispersibility, high specificity to cancer cells and strong MR imaging efficacy

Xuehua Ma,An Gong,Bin Chen,Jianjun Zheng,Tianxiang Chen,Zheyu Shen,Aiguo Wu

Advances in contrast agents have greatly enhanced the sensitivity of magnetic resonance imaging (MRI) technique for early diagnosis of cancer. However, the commercial superparamagnetic iron oxide nanoparticles (SPION)-based contrast agents synthesized by co-precipitation method are not monodisperse with irregular morphologies and ununiform sizes. Other reported SPION-based contrast agents synthesized by solvothermal method or thermal decomposition method are limited by the bad water-dispersibility and low specificity to cancer cells. Herein, we propose a new strategy for exploring SPION-based MRI contrast agents with excellent water-dispersibility and high specificity to cancer cells. The SPION was synthesized by a polyol method and then entrapped into albumin nanospheres (AN). After that, a ligand folic acid (FA) was conjugated onto the surface of the AN to construct a SPION-AN-FA composite. The transmission electron microscope (TEM) and dynamic light scattering (DLS) results indicate that the SPION-AN-FA has a spherical shape, a uniform size and an excellent water-dispersibility (polydispersity index (PDI) <0.05). The results of laser scanning confocal microscope (LSCM) and flow cytometry demonstrate that the SPION-AN-FA nanoparticles are highly specific to MCF-7 and SPC-A-1 cells due to the recognition of ligand FA and folate receptor α (FRα). The r 2 / r 1 value of SPION-AN-FA is around 40, which is much higher than that of Resovist ® indicating that our SPION-AN-FA has a stronger T 2 shortening effect. The T 2 -weighted images of MCF-7 cells incubated with SPION-AN-FA are significantly darker than those of MCF-7 cells incubated with AN, indicating that our SPION-AN-FA has a strong MR imaging efficacy. In view of the excellent water-dispersibility, the high specificity to cancer cells and the strong MR imaging efficacy, our SPION-AN-FA can be used as a negative MR contrast agent.

Preparation and evaluation of LA-PEG-SPION, a targeted MRI contrast agent for liver cancer

Lei Xia,Xiaowei Song,Guanghai Yan,Jishan Quan,Guangyu Jin

This study aims to synthesize a magnetic resonance imaging (MRI) contrast agent that can specifically target the asialoglycoprotein receptor of liver cancer cells and evaluate its ability as a targeted MRI contrast agent. Lactobionic acid (LA) and polyethylene glycol (PEG) were used to modify superparamagnetic iron oxide nanoparticles (SPION) to obtain LA-PEG-SPION. LA-PEG-SPION was uniformly spherical under the electron microscope, with regular morphology and good dispersion. The particle size of LA-PEG-SPION was about 30 ± 4.5 nm, and its surface potential was about 31 ± 1.5 mV. LA-PEG-SPION had no toxicity or low toxicity to HepG2 cells and HeLa cells, even at 400 μg/mL. The uptake of LA-PEG-SPION by HepG2 cells was higher than that of SPION, with increased blue-stained particles. The fluorescent labeling rate of HepG2 cells reached 68.8%, which was higher than that of the control group. In vitro, MRI showed that the T2-weighted signal intensity of HepG2 cells was lower than that of the control group. Conclusively, LA-PEG-SPION nanoparticles are synthesized in a simple and efficient way. They are successfully applied to the T2-weighted contrast-enhanced MRI in liver cancer in vitro , and they have the potential to be used for in vivo research and clinical studies.

A rheumatoid arthritis magnetic resonance imaging contrast agent based on folic acid conjugated PEG-b-PAA@SPION

Yanqi Zhong,Fengying Dai,Heng Deng,Meihong Du,Xiaoning Zhang,Qingjun Liu,Xin Zhang

Superparamagnetic iron oxide nanoparticles (SPIONs) offer unique properties for magnetic resonance imaging (MRI). Targeting imaging of rheumatoid arthritis in vivo requires a specific, magnetic sensitive and ultra-stable MRI contrast agent. In this study, SPIONs with a preferable colloid stability and optimized size were obtained by using an in situ polyol method with the diblock copolymer PEG-b-PAA acting as a surface ligand. Increasing the degree of polymerization (DP) of PAA from 18 to 36 to 57 led to the decreasing size of the iron oxide nanoparticles from 52 nm to 17 nm to 9 nm, respectively. Folic acid was conjugated onto PEG-PAAx@SPION as a specific targeting molecule for activated macrophages in a rheumatoid arthritis joint. To evaluate the stability and magnetic properties of the particle, a series of tests were conducted to evaluate and optimize the nanoparticles. In vitro endocytosis experiments confirmed the better performance of the folic acid conjugated SPIONs than the non-folic acid modified SPIONs. In vivo MRI clearly demonstrated the significant signal diminishment of the arthritis joint in antigen induced arthritis (AIA) rats by intravenous injection of the optimized nanoparticles FA–PEG-b-PAA36@SPION. These results indicated that FA–PEG-b-PAA36@SPION could serve as a promising candidate for the MRI of rheumatoid arthritis.

Controlled SPION-Exosomes Loaded with Quercetin Preserves Pancreatic Beta Cell Survival and Function in Type 2 Diabetes Mellitus

Manjiao Zhuang,Lei Rao,Yadi Chen,Shangying Xiao,Haishan Xia,Jiangyong Yang,Xiaohua Lv,Dongyun Qin,Chunjie Zhu

A Supersensitive CTC Analysis System Based on Triangular Silver Nanoprisms and SPION with Function of Capture, Enrichment, Detection, and Release

Huimin Ruan,Xiaoxia Wu,Chengcheng Yang,Zihou Li,Yuanzhi Xia,Ting Xue,Zheyu Shen,Aiguo Wu

Detection of circulating tumor cells (CTCs) may be applied for diagnosis of early tumors like a liquid biopsy. However, the sensitivity remains a challenge because CTCs are extremely rare in peripheral blood. In this study, we developed a supersensitive CTC analysis system based on triangular silver nanoprisms (AgNPR) and superparamagnetic iron oxide nanoparticles (SPION) with function of capture, enrichment, detection, and release. The AgNPR was encoded with MBA (i.e., 4-mercaptobenzoic acid) and modified with rBSA (i.e., reductive bovine serum albumin) and FA (i.e., folic acid) generating organic/inorganic composite nanoparticle MBA-AgNPR-rBSA-FA, which has the function of surface-enhanced Raman scattering (SERS). The optimized SERS nanoparticles (i.e., MBA3-AgNPR-rBSA4-FA2) can be utilized for CTC detection in blood samples with high sensitivity and specificity, and the LOD (i.e., limit of detection) reaches to five cells per milliliter. In addition, the SPION was also modified with rBSA and FA generating magnetic nanoparticle SPION-rBSA-FA. Our supersensitive CTC analysis system is composed of MBA3-AgNPR-rBSA4-FA2 and SPION-rBSA-FA nanoparticles, which were applied for capture (via interaction between FA and FRα), enrichment (via magnet), and detection (via SERS) of cancer cells from blood samples. The results demonstrate that our supersensitive CTC analysis system has a better sensitivity and specificity than the SERS nanoparticles alone, and the LOD is up to 1 cell/mL. The flow cytometry and LSCM (i.e., laser scanning confocal microscope) results indicate the CTCs captured, enriched, and isolated by our supersensitive CTC analysis system can also be further released (via adding excessive free FA) for further cell expansion and phenotype identification.

A three-dimensional-printed SPION/PLGA scaffold for enhanced palate-bone regeneration and concurrent alteration of the oral microbiota in rats

Lu Jia,Zukun Yang,Liuxu Sun,Qian Zhang,Yu Guo,Yulian Chen,Yang Dai,Yang Xia

Scaffold implantation for the repair of oral bone defects involves an interplay between the scaffold biomaterial and the microenvironment. However, previous studies on this subject have only considered the effects of the immune system and largely ignored those of the oral microbiota. Accordingly, in the present study, we prepared composite scaffolds comprising a three-dimensional poly( l -lactide- co -glycolide) matrix with a superparamagnetic iron oxide nanoparticle (SPION) coating and used a rat model to evaluate their palate-bone-regenerating effects and their interaction with the oral microbiota. It was found that the SPION coated scaffold induced better bone regeneration than that achieved by the controls. Furthermore, it significantly decreased the operational taxonomic units (OTU) numbers as determined by 16 s rRNA gene sequencing, and also resulted in decreased Chao and ACE alpha diversity indexes compared with those of the controls. However, it had no effect on beta diversity. SPION coated scaffolds caused a shift in oral bacterial composition characterized by a decrease in the Clostridium spp. population, and the dominant flora being Proteobacteria . Furthermore, SPION coated scaffolds upregulated the concentration of serum iron, hepcidin, and P1NP. Thus, SPION coated scaffolds enhanced bone regeneration, and this effect was partly related to alteration of the oral microbiota by the antibacterial effects of SPION. Our findings provide a better understanding of the role of oral microbiota in oral bone regeneration and how SPION coated scaffolds can be used to enhance it.

A Contrast-Enhanced Tri-Modal MRI Technique for High-Performance Hypoxia Imaging of Breast Cancer

Quanliang Mao,Mengyin Gu,Chengyuan Hong,Huiying Wang,Xinzhong Ruan,Zhusheng Liu,Bo Yuan,Mengting Xu,Chen Dong,Lei Mou,Xiang Gao,Guangyu Tang,Tianxiang Chen,Aiguo Wu,Yuning Pan

Personalized radiotherapy strategies enabled by the construction of hypoxia-guided biological target volumes (BTVs) can overcome hypoxia-induced radioresistance by delivering high-dose radiotherapy to targeted hypoxic areas of the tumor. However, the construction of hypoxia-guided BTVs is difficult owing to lack of precise visualization of hypoxic areas. This study synthesizes a hypoxia-responsive T 1 , T 2 , T 2 mapping tri-modal MRI molecular nanoprobe (SPION@ND) and provides precise imaging of hypoxic tumor areas by utilizing the advantageous features of tri-modal magnetic resonance imaging (MRI). SPION@ND exhibits hypoxia-triggered dispersion-aggregation structural transformation. Dispersed SPION@ND can be used for routine clinical BTV construction using T 1 -contrast MRI. Conversely, aggregated SPION@ND can be used for tumor hypoxia imaging assessment using T 2 -contrast MRI. Moreover, by introducing T 2 mapping, this work designs a novel method (adjustable threshold-based hypoxia assessment) for the precise assessment of tumor hypoxia confidence area and hypoxia level. Eventually this work successfully obtains hypoxia tumor target and accurates hypoxia tumor target, and achieves a one-stop hypoxia-guided BTV construction. Compared to the positron emission tomography-based hypoxia assessment, SPION@ND provides a new method that allows safe and convenient imaging of hypoxic tumor areas in clinical settings.

Advancing the Frontiers of Neuroelectrodes: A Paradigm Shift towards Enhanced Biocompatibility and Electrochemical Performance

Qin Wang,Yiyang Liu,Baolin Zhang,Jianghui Dong,Liping Wang

The aim of this study is the fabrication of unprecedented neuroelectrodes, replete with exceptional biological and electrical attributes. Commencing with the synthesis of polyethylene glycol and polyethyleneimine-modified iron oxide nanoparticles, the grafting of Dimyristoyl phosphatidylcholine was embarked upon to generate DMPC-SPION nanoparticles. Subsequently, the deposition of DMPC-SPIONs onto a nickel–chromium alloy electrode facilitated the inception of an innovative neuroelectrode–DMPC-SPION. A meticulous characterization of DMPC-SPIONs ensued, encompassing zeta potential, infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction analyses. Evaluations pertaining to hemolysis and cytotoxicity were conducted to ascertain the biocompatibility and biosafety of DMPC-SPIONs. Ultimately, a comprehensive assessment of the biocompatibility, electrochemical properties, and electrophysiological signal acquisition capabilities of DMPC-SPION neuroelectrodes was undertaken. These findings conclusively affirm the exemplary biocompatibility, electrochemical capabilities, and outstanding capability in recording electrical signals of DMPC-SPION neuroelectrodes, with an astounding 91.4% augmentation in electrode charge and a noteworthy 13% decline in impedance, with peak potentials reaching as high as 171 μV and an impressive signal-to-noise ratio of 15.92. Intriguingly, the novel DMPC-SPION neuroelectrodes herald an innovative pathway towards injury repair as well as the diagnosis and treatment of neurological disorders.

A SERS-machine learning quantitative detection platform for Pseudomonas aeruginosa based on AuNRs-MBA@Ag-MBA-van SERS tag and SPION-PEI-AuNPs-apt magnetic beads

Clement Yaw Effah,Longlong Tan,Qimeng Zhang,Xinyu Li,Lijun Miao,Xiaolei Zhou,Lihua Ding,Yongjun Wu

Pseudomonas aeruginosa ( PA ) is an opportunistic pathogen that is widely distributed in soil, water, air, food, animal, and human body surfaces, and is also one of the main pathogens of iatrogenic infections which can cause various infections in people with weakened immune systems. The rapid detection of PA in varied environmental and clinical samples is important for hospital infection control, clinical diagnosis, and food and environmental safety monitoring. In this study, we constructed an efficient separation and enrichment surface-enhanced Raman scattering (SERS) platform based on a dual recognition strategy, and supplemented it with a machine learning nonlinear regression model to achieve rapid, highly sensitive, accurate, and specific detection of PA. By combining the SERS platform with support vector machine learning regression model, a detection limit of 15 CFU/mL with a liner range of 50 to 10 8 cells/mL was achieved. The highly sensitive dual-identification tag-type SERS quantitative analysis system established in this study has the advantages of wide detection range, low detection limit, good specificity, high accuracy and short detection time, thereby providing a method for the prevention and clinical diagnosis of PA infection-related diseases as well as food and environmental safety monitoring.

Water-Stable Magnetic Lipiodol Micro-Droplets as a Miniaturized Robotic Tool for Drug Delivery

En Ren,Jing Hu,Ziyang Mei,Lin Lin,Qian Zhang,Pan He,Junqing Wang,Tao Sheng,Hu Chen,Hongwei Cheng,Tiantian Xu,Shiyao Pang,Yang Zhang,Qixuan Dai,Xing Gao,Hui Liu,Hongjun Li,Yang Zhao,Zhen Gu,Xiaohui Yan,Gang Liu

Magnetic microrobots, designed to navigate the complex environments of the human body, show promise for minimally invasive diagnosis and treatment. However, their clinical adoption faces hurdles such as biocompatibility, precise control, and intelligent tracking. Here a novel formulation (referred to water-stable magnetic lipiodol micro-droplets, MLMD), integrating clinically approved lipiodol, gelatin, and superparamagnetic iron oxide nanoparticles (SPION) with a fundamental understanding of the structure-property relationships is presented. This formulation demonstrates multiple improved properties including flowability, shape adaptability, efficient drug loading, and compatibility with digital subtraction angiography (DSA) imaging in both in vitro and in vivo experiments. This enables the MLMD as a versatile tool for image-guided therapy, supported by a close-looped magnetic navigation system featuring artificial intelligence (AI)-driven visual feedback for autonomous control. The system effectively performs navigational tasks, including pinpointing specific locations of MLMD, recognizing and avoiding obstacles, mapping and following predetermined paths, and utilizing magnetic fields for precise motion planning to achieve visual drug delivery. The MLMD combines magnetic actuation with an AI-directed close-looped navigation, offering a transformative platform for targeted therapeutic delivery.

pH protective Y1 receptor ligand functionalized antiphagocytosis BPLP-WPU micelles for enhanced tumor imaging and therapy with prolonged survival time

Zhenqi Jiang,Yuchen Tian,Dingying Shan,Yinjie Wang,Ethan Gerhard,Jianbi Xia,Rong Huang,Yan He,Aiguo Li,Jianchao Tang,Huimin Ruan,Yong Li,Juan Li,Jian Yang,Aiguo Wu

Nanoparticle-based tumor therapies are extensively studied; however, few are capable of improving patient survival time due to premature drug leakage, off target effects, and poor tissue penetration. Previously, we successfully synthesized a novel family of Y 1 receptor (Y 1 R) ligand modified, photoluminescent BPLP nanobubbles and nanoparticles for targeted breast cancer ultrasound imaging ; however, increased accumulation could also be observed in the liver, kidney, and spleen, suggesting significant interaction of the particles with macrophages in vivo . Herein, for the first time, we imparted antiphagocytosis capability to Y 1 R ligand functionalized BPLP-WPU polymeric micelles through the incorporation of a CD47 human glycoprotein based self-peptide. Application of self-peptide modified, DOX loaded micelles in vivo resulted in a 100% survival rate and complete tumor necrosis over 100 days of treatment. In vivo imaging of SPION loaded, self-peptide modified micelles revealed effective targeting to the tumor site while analysis of iron content demonstrated reduced particle accumulation in the liver and kidney, demonstrating reduced macrophage interaction, as well as a 2-fold increase of particles in the tumor. As these results demonstrate, Y 1 R ligand, self-peptide modified BPLP-WPU micelles are capable of target specific cancer treatment and imaging, making them ideal candidates to improve survival rate and tumor reduction clinically.