scholarly journals Polypyrrole-Coated Magnetite Vortex Nanoring for Hyperthermia-Boosted Photothermal/Magnetothermal Tumor Ablation Under Photoacoustic/Magnetic Resonance Guidance

Author(s):  
Jianfeng Bao ◽  
Shuangshuang Guo ◽  
Xiangyang Zu ◽  
Yuchuan Zhuang ◽  
Dandan Fan ◽  
...  

Photothermal/magnetothermal-based hyperthermia cancer therapy techniques have been widely investigated, and associated nanotechnology-assisted treatments have shown promising clinical potentials. However, each method has some limitations, which have impeded extensive applications. For example, the penetration ability of the photothermal is not satisfactory, while the heating efficiency of the magnetothermal is very poor. In this study, a novel magnetite vortex nanoring nanoparticle-coated with polypyrrole (denoted as nanoring Fe3O4@PPy-PEG) was first synthesized and well-characterized. By combining photothermal and magnetothermal effects, the performance of the dual-enhanced hyperthermia was significantly improved, and was thoroughly examined in this study. Benefiting from the magnetite vortex nanoring and polypyrrole, Fe3O4@PPy-PEG showed excellent hyperthermia effects (SAR = 1,648 Wg–1) when simultaneously exposed to the alternating magnetic field (300 kHz, 45 A) and near-infrared (808 nm, 1 W cm–2) laser. What is more, nanoring Fe3O4@PPy-PEG showed a much faster heating rate, which can further augment the antitumor effect by incurring vascular disorder. Besides, Fe3O4@PPy-PEG exhibited a high transverse relaxation rate [60.61 mM–1 S–1 (Fe)] at a very low B0 field (0.35 T) and good photoacoustic effect. We believe that the results obtained herein can significantly promote the development of multifunctional nanoparticle-mediated magnetic and photo induced efficient hyperthermia therapy.

P. m. r. relaxation times ( T 1 and T 2 ) have been measured as a function of regain and temperature for water sorbed by lyophilized methaemoglobin. The purpose of the work was to gain information regarding the nature and extent of water binding by the protein molecules. The T 1 results are interpreted in terms of an exchange between the sixth ligand position of the Fe (III) and other adsorption sites on the protein. At high temperatures the relaxation rate at a given regain reaches a limiting value which allows the fraction of ferric ions hydrated to be calculated. Above 16% regain all the Fe (III) is hydrated. At 21 and 35% regains a maximum appears in the relaxation rate at about -46 °C indicating a contribution from a more mobile phase which produces a T 1 minimum at that temperature. The T 2 data are consistent with a model in which the main contribution to the transverse relaxation rate comes from a tightly bound fraction of the water with ω 0 Ƭ c ≫1. The temperature dependence of T 2 exhibits three different regions: ( a ) a low temperature region where lg T 2 ∝ T -1 ; ( b ) an intermediate region with a steeper increase of T 2 with temperature; and ( c ) a high temperature where T 2 levels off.


Author(s):  
Yinghui Wang ◽  
Ying Zhao ◽  
Yang Liu ◽  
Qishun Wang ◽  
Jianhua Liu ◽  
...  

Photothermal therapy (PTT) stimulated by the lights in the second near-infrared (NIR-II) biowindow shows great superiorities in penetration ability of tissue and maximum permissible exposure (MPE). Exploring new photothermal agents...


2007 ◽  
Vol 58 (5) ◽  
pp. 1054-1060 ◽  
Author(s):  
Fumiyuki Mitsumori ◽  
Hidehiro Watanabe ◽  
Nobuhiro Takaya ◽  
Michael Garwood

2018 ◽  
Vol 148 ◽  
pp. 501-507 ◽  
Author(s):  
Liaoliao Li ◽  
Dong Wang ◽  
Lei Wang ◽  
Daniele Ramella ◽  
Hao Wang ◽  
...  

Nanomedicine ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 219-234 ◽  
Author(s):  
Isabel Ortiz de Solorzano ◽  
Martin Prieto ◽  
Gracia Mendoza ◽  
Victor Sebastian ◽  
Manuel Arruebo

Aim: Developing hybrid poly(N-isopropylacrylamide)-based nanogels decorated with plasmonic hollow gold nanoparticles for on-demand drug delivery and their physico-chemical characterization, bupivacaine loading and release ability upon light irradiation, and in vitro cell viability. Materials & methods: Hollow gold nanoparticles were prepared by galvanic replacement reaction; poly(N-isopropylacrylamide)-based nanogels were synthesized via precipitation polymerization and their electrostatic coupling was accomplished using poly(allylamine hydrochloride) as cationic polyelectrolyte linker. Results & conclusion: Colloidal stability of the resulted hybrid nanovectors was demonstrated under physiological conditions together with their fast response and excellent heating efficiency after light stimulation, indicating their potential use as triggered drug-delivery vectors. Moreover, their influence on cell metabolism and cell cycle under subcytotoxic doses were studied showing excellent cytocompatibility.


2015 ◽  
Vol 5 ◽  
pp. 1 ◽  
Author(s):  
Grigorios Gotzamanis ◽  
Roman Kocian ◽  
Pinar S. Özbay ◽  
Manuel Redle ◽  
Spyridon Kollias ◽  
...  

Objectives: This study aims to quantify the response of the transverse relaxation rate of the magnetic resonance (MR) signal of the cerebral tissue in healthy volunteers to the administration of air with step-wise increasing percentage of oxygen. Materials and Methods: The transverse relaxation rate (R2*) of the MR signal was quantified in seven volunteers under respiratory intake of normobaric gas mixtures containing 21, 50, 75, and 100% oxygen, respectively. End-tidal breath composition, arterial blood saturation (SaO2), and heart pulse rate were monitored during the challenge. R2* maps were computed from multi-echo, gradient-echo magnetic resonance imaging (MRI) data, acquired at 3.0T. The average values in the segmented white matter (WM) and gray matter (GM) were tested by the analysis of variance (ANOVA), with Bonferroni post-hoc correction. The GM R2*-reactivity to hyperoxia was modeled using the Hill's equation. Results: Graded hyperoxia resulted in a progressive and significant (P < 0.05) decrease of the R2* in GM. Under normoxia the GM-R2* was 17.2 ± 1.1 s-1. At 75% O2 supply, the R2* had reached a saturation level, with 16.4 ± 0.7 s-1 (P = 0.02), without a significant further decrease for 100% O2. The R2*-response of GM correlated positively with CO2 partial pressure (R = 0.69 ± 0.19) and negatively with SaO2 (R = -0.74 ± 0.17). The WM showed a similar progressive, but non-significant, decrease in the relaxation rates, with an increase in oxygen intake (P = 0.055). The Hill's model predicted a maximum R2* response of the GM, of 3.5%, with half the maximum at 68% oxygen concentration. Conclusions: The GM-R2* responds to hyperoxia in a concentration-dependent manner, suggesting that monitoring and modeling of the R2*-response may provide new oxygenation biomarkers for tumor therapy or assessment of cerebrovascular reactivity in patients.


2018 ◽  
Vol 6 (9) ◽  
pp. 2460-2471 ◽  
Author(s):  
Xiuhua Wang ◽  
Lei Tan ◽  
Xiangmei Liu ◽  
Zhenduo Cui ◽  
Xianjin Yang ◽  
...  

Near infrared (NIR) light induced photodynamic antibacterial therapy (PDAT) is a promising antibacterial technique in rapidin situdisinfection of bacterially infected artificial implants due to its penetration ability into tissues.


2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi174-vi175
Author(s):  
Jingwen Yao ◽  
David Nathanson ◽  
William H Yong ◽  
Noriko Salamon ◽  
Albert Lai ◽  
...  

Abstract 1p/19q co-deleted gliomas are known to have slower growth rates and are more sensitive to chemotherapy and radiotherapy. This may be partially explained by the lower tumor acidosis compared to non-co-deleted gliomas, as extracellular acidosis is one of the driving forces toward tumor invasion and resistance to treatments. Amine CEST-EPI is a fast chemical exchange saturation transfer (CEST) imaging technique sensitive to decreased extracellular pH, transverse relaxation rate, and amino acid concentration. In the current study, we demonstrated that 1p/19q co-deleted gliomas are less acidic than non-co-deleted gliomas, using a combination of pH-sensitive amineCEST-EPI, T2 relaxometry, and 18F-FDOPA (18[F] fluorodopa) amino acid PET. 70 histologically-confirmed glioma patients (World Health Organization WHO grade II, N=35; grade III, N=35) received amine CEST-EPI scans. Among them, 16 patients received 18F-FDOPA PET scan and 45 patients received T2 relaxometry quantification. Mann-Whitney u-test is performed to evaluate the differences. Median MTRasym at 3ppm (magnetization transfer ratio asymmetry at amine proton resonance frequency) within T2 hyperintense lesions was significantly lower in 1p/19q co-deleted gliomas compared to non-co-deleted ones (co-deleted 1.19±0.31%; non-co-deleted 1.66±0.45%; p< 0.0001). The significantly lower MTRasym persists when comparing within grade II (p=0.003), grade III (p=0.031), IDH1 mutated gliomas (p=0.002), and gliomas exhibiting classical oligodendroglial histology (p=0.0007). The ROC analysis shows that the prediction of 1p/19q status using MTRasym has area under the curve (AUC) of 0.80 (sensitivity 75.6%. specificity 72.7%). Median FDOPA and T2 in T2-hyperintense lesions were not different between 1p/19q co-deleted and non-co-deleted tumors (FDOPA p=0.84; T2 p=0.63). Results suggest 1p/19q co-deleted gliomas have notably lower acidity compared with non-co-deleted gliomas, as indicated by lower MTRasym and no differences in amino acid concentration or transverse relaxation rate. Further, data indicate the 1p/19q co-deleted gliomas may have distinct metabolic characteristics and tumor microenvironment that can be measured using pH-sensitive amineCEST-MRI at 3T.


2019 ◽  
Vol 164 ◽  
pp. 182-187 ◽  
Author(s):  
ZhiHao Zhao ◽  
Dong Wang ◽  
Hong Gao ◽  
Zhou Yang ◽  
Hui Cao ◽  
...  

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