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1.
Molecules ; 29(17)2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39274923

RESUMEN

The present study explores the synthesis and bio-safety evaluation of gadolinium-doped carbon quantum dots (GCQDs) as a potential dual-contrast agent for diagnostic imaging. GCQDs exhibit both fluorescent and magnetic properties, making them suitable for UV-Vis and magnetic resonance imaging (MRI). The synthesis of GCQDs was achieved via hydrothermal treatment, incorporating gadolinium into the carbon quantum dot matrix. The magnetic properties of GCQDs were analyzed, showing significantly enhanced values compared to gadobutrol, a common MRI contrast agent. However, synthesis constraints limit the gadolinium content achievable in nanodots. To assess the safety of GCQDs, their effects on the embryonic development of zebrafish (Danio rerio) were examined. Various concentrations of GCQDs were tested, observing mortality rates, hatchability, malformations, heartbeats, spontaneous movement, and GCQDs uptake. Dialysis studies indicated that gadolinium ions are incorporated into the internal structure of the carbon nanodots. Zebrafish toxicity tests revealed that while survival rates were comparable to control groups, hatchability decreased significantly with higher gadolinium concentrations in GCQDs. Fluorescence microscopy showed no statistical differences in the fluorescence intensity between groups. These findings suggest that GCQDs could serve as an effective dual-contrast agent, combining the optical imaging capabilities of CQDs with the enhanced MRI contrast provided by gadolinium. This study underscores the need for further research on the synthesis methods and biological interactions of GCQDs to ensure their safety and efficacy in medical applications.


Asunto(s)
Carbono , Medios de Contraste , Gadolinio , Imagen por Resonancia Magnética , Puntos Cuánticos , Pez Cebra , Puntos Cuánticos/química , Puntos Cuánticos/toxicidad , Gadolinio/química , Medios de Contraste/química , Medios de Contraste/síntesis química , Animales , Pez Cebra/embriología , Carbono/química , Imagen por Resonancia Magnética/métodos , Diagnóstico por Imagen/métodos
2.
Langmuir ; 40(33): 17337-17347, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39113429

RESUMEN

Advanced methodologies, such as hyperthermia and modulation of reactive oxygen species (ROS), exhibit considerable promise in the therapeutic landscape of cancer. These strategies offer a targeted paradigm for combating malignant cells while mitigating damage to healthy tissue. Noteworthy among these approaches is the utilization of superparamagnetic iron oxide nanoparticles, which are renowned for their ability to enhance both hyperthermia and ROS generation specifically within tumor microenvironments. The objective of this investigation is to scrutinize the relationship between the reaction duration and the characteristics of carbon-doped silica core-shell iron oxide nanoparticles (CSIONPs). Specifically, we focus on CSIONP-12, CSIONP-24, and CSIONP-36, synthesized by using varying reaction periods. Through a comprehensive analysis, we primarily evaluate the impact of these formulations on T1 and T2 magnetic resonance imaging (MRI), aiming to elucidate their mechanisms and therapeutic potential in promoting hyperthermia and ROS-mediated cancer therapy. CSIONP-24 emerges as a compelling candidate due to its dual influence on magnetic hyperthermia and ROS generation, suggesting its promise in enhancing cancer treatment outcomes. Furthermore, the findings underscore the exceptional T1-T2 MRI capabilities of this technology, underscoring its versatility and efficacy in the nuanced realm of cancer theranostic.


Asunto(s)
Medios de Contraste , Hipertermia Inducida , Imagen por Resonancia Magnética , Especies Reactivas de Oxígeno , Especies Reactivas de Oxígeno/metabolismo , Imagen por Resonancia Magnética/métodos , Hipertermia Inducida/métodos , Humanos , Medios de Contraste/química , Medios de Contraste/síntesis química , Medios de Contraste/farmacología , Nanopartículas Magnéticas de Óxido de Hierro/química , Dióxido de Silicio/química , Animales
3.
J Med Chem ; 67(17): 15476-15493, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39190821

RESUMEN

Hepatobiliary-specific magnetic resonance imaging contrast agents (MRI CAs) play a crucial role in the early diagnosis of hepatocellular carcinoma (HCC). However, only two acyclic CAs, Gd-BOPTA and Gd-EOB-DTPA, exhibit unfavorable kinetic inertness. Our study focused on the development of superior stable innovative macrocyclic CAs. By introducing a lipophilic benzyloxy group (OBn) into the H4DOTA ring (Gd-L1), we achieved significant enhancement in kinetic inertness. In vivo experiments in mice demonstrated that 40% of the dosage was distributed to the liver at 5 min, providing sustained hepatic enhancement for over 35 min. We also developed an MPO-responsive MRI CA (Gd-L3), which can participate in the "peroxidase cycle" as the substrate, generating oligomers with a 3.8-fold increase in relaxivity, and selectively enhance the lesion in an acute gout mouse model. Overall, our work represents a significant advancement in the field of hepatic and inflammatory MRI, offering promising avenues for early diagnosis and improved imaging outcomes.


Asunto(s)
Medios de Contraste , Hígado , Imagen por Resonancia Magnética , Compuestos Organometálicos , Medios de Contraste/química , Medios de Contraste/síntesis química , Animales , Imagen por Resonancia Magnética/métodos , Ratones , Compuestos Organometálicos/química , Compuestos Organometálicos/síntesis química , Hígado/diagnóstico por imagen , Hígado/metabolismo , Diseño de Fármacos , Humanos , Inflamación/diagnóstico por imagen , Masculino , Neoplasias Hepáticas/diagnóstico por imagen , Carcinoma Hepatocelular/diagnóstico por imagen , Compuestos Heterocíclicos
4.
Org Biomol Chem ; 22(31): 6308-6320, 2024 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-39037740

RESUMEN

Amide bonds are one of the most prevalent phenomena in nature and are utilized frequently in drug and material design. However, forming amide bonds is not always efficient or high yielding, particularly when the amine used to conjugate to a carboxylic acid is a weak nucleophile. This limitation precludes many useful amino compounds from participating in conjugation reactions to form amides. A particularly valuable amino compound, which is also a very weak nucleophile, is the amino porphyrin, valued for its role as a photosensitizer, fluorescent agent, catalyst, or, upon metalation, even a very efficient contrast agent for magnetic resonance imaging (MRI). In this work, we propose fast and high-yield coupling of an unreactive amine - the amino porphyrin - to carboxylic acid via isothiocyanate conjugation. Reactions can be achieved in one step at room temperature in one hour, achieving quantitative conversion and near perfect selectivity. Both metalated and unmetalated porphyrin, as well as fluorescein isothiocyanate (FITC), demonstrated efficient conjugation. To illustrate the value of the proposed method, we created a new blood-pool MRI contrast agent that reversibly binds to serum albumin. This new blood-pool agent, known as MITC-Deox (MRI isothiocyanate that links with deoxycholic acid), substantially reduced T1 relaxation times in blood vessels in mice, remained stable for 1 hour, cleared from blood by 24 hours, and was eliminated from the body after 4 days. The proposed method for efficient amide formation is a superior alternative to existing coupling methods, opening a door to novel synthesis of MRI contrast agents and beyond.


Asunto(s)
Amidas , Medios de Contraste , Porfirinas , Porfirinas/química , Porfirinas/síntesis química , Amidas/química , Amidas/síntesis química , Animales , Ratones , Medios de Contraste/química , Medios de Contraste/síntesis química , Imagen por Resonancia Magnética , Estructura Molecular , Isotiocianatos/química , Fluoresceína-5-Isotiocianato/química
5.
J Mater Chem B ; 12(29): 7090-7102, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38984662

RESUMEN

Magnetic resonance imaging (MRI) has emerged as a pivotal tool in contemporary medical diagnostics, offering non-invasive and high-resolution visualization of internal structures. Contrast agents are essential for enhancing MRI resolution, accurate lesion detection, and early pathology identification. While gadolinium-based contrast agents are widely used in clinics, safety concerns have prompted exploration of metal-free alternatives, including fluorine and nitroxide radical-based MRI contrast agents. Fluorine-containing compounds exhibit excellent MRI capabilities, with 19F MRI providing enhanced resolution and quantitative assessment. Nitroxide radicals, such as PROXYL and TEMPO, offer paramagnetic properties for MRI contrast. Despite their versatility, nitroxide radicals suffer from lower relaxivity values (r1) compared to gadolinium. Dual-modal imaging, combining 1H and 19F MRI, has gained prominence for its comprehensive insights into biological processes and disease states. However, existing dual-modal agents predominantly utilize gadolinium-organic ligands without incorporating nitroxide radicals. Here, we introduce a novel dual-modal MRI contrast agent (J-CA) featuring a Janus asymmetric nanostructure synthesized via seeded emulsion polymerization and post-modification. J-CA demonstrates excellent in vitro and in vivo performance in both 19F and 1H MRI, with a T2 relaxation time of 5 ms and an r1 value of 0.31 mM-1 s-1, ensuring dual-modal imaging capability. Moreover, J-CA exhibits superior biocompatibility and organ targeting, making it a promising candidate for precise lesion imaging and disease diagnosis. This work introduces a new avenue for metal-free dual-modal MRI, addressing safety concerns associated with traditional contrast agents.


Asunto(s)
Medios de Contraste , Imagen por Resonancia Magnética , Nanoestructuras , Polímeros , Medios de Contraste/química , Medios de Contraste/síntesis química , Imagen por Resonancia Magnética/métodos , Animales , Ratones , Nanoestructuras/química , Polímeros/química , Humanos , Flúor/química , Tamaño de la Partícula
6.
J Mater Chem B ; 12(26): 6371-6383, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38864345

RESUMEN

The self-assembly of peptides and peptide analogues may be exploited to develop platforms for different biomedical applications, among which CEST-MRI (chemical exchange saturation transfer magnetic resonance imaging) represents one of the most attractive techniques to be explored as a novel metal-free contrast approach in imaging acquisitions. A lysine-containing peptide sequence (LIVAGK-NH2, named K2) was thus modified by insertion, at the N-terminus, of a peptide nucleic acid (PNA) base, leading to a primary amine suitable for the signal generation. a-K2, c-K2, g-K2 and t-K2 peptides were synthesized and characterized. The c-K2 sequence displayed gelling properties and the Watson and Crick pairing, arising from its combination with g-K2, allowed a significant increase in the mechanical responsivity of the hydrogel. These matrices were able to generate a CEST signal around 2.5 ppm from water and, after assessing their cytocompatibility on GL261 (murine glioma), TS/a (murine breast carcinoma), and 3T3-NIH (murine fibroblasts) cell lines, their capability to work as implants for in vivo detection, was proved by intratumor injection in Balb/c mice inoculated with TS/a murine breast cancer cells.


Asunto(s)
Medios de Contraste , Hidrogeles , Imagen por Resonancia Magnética , Ratones Endogámicos BALB C , Ácidos Nucleicos de Péptidos , Péptidos , Animales , Hidrogeles/química , Hidrogeles/síntesis química , Ratones , Ácidos Nucleicos de Péptidos/química , Péptidos/química , Péptidos/síntesis química , Medios de Contraste/química , Medios de Contraste/síntesis química , Femenino , Células 3T3 NIH , Línea Celular Tumoral
7.
J Med Chem ; 67(11): 8630-8641, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38747630

RESUMEN

A novel Fe(III) complex, Fe-tBPCDTA, was synthesized and explored as a potential contrast agent for MRI. Compared to established agents like Fe-EDTA and Fe-tCDTA, Fe-tBPCDTA exhibited moderate relaxivity (r1 = 1.17 s-1·mmol-1) due to its enhanced second-sphere mechanism. It also displayed improved kinetic inertness, lower cytotoxicity, and enhanced redox stability. In vivo studies demonstrated its function as an extracellular fluid agent, providing tumor contrast comparable to that of Gd-DTPA at a higher dosage. Complete renal clearance occurred within 24 h. These findings suggest Fe-tBPCDTA as a promising candidate for further development as a safe and effective extracellular MRI contrast agent.


Asunto(s)
Medios de Contraste , Quelantes del Hierro , Imagen por Resonancia Magnética , Organofosfonatos , Medios de Contraste/química , Medios de Contraste/síntesis química , Imagen por Resonancia Magnética/métodos , Animales , Humanos , Organofosfonatos/química , Organofosfonatos/síntesis química , Quelantes del Hierro/química , Quelantes del Hierro/farmacología , Quelantes del Hierro/síntesis química , Compuestos Férricos/química , Ratones , Línea Celular Tumoral , Quelantes/química , Quelantes/síntesis química
8.
Bioconjug Chem ; 35(5): 703-714, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38708860

RESUMEN

Manganese(II)-based contrast agents (MBCAs) are potential candidates for gadolinium-free enhanced magnetic resonance imaging (MRI). In this work, a rigid binuclear MBCA (Mn2-PhDTA2) with a zero-length linker was developed via facile synthetic routes, while the other dimer (Mn2-TPA-PhDTA2) with a longer rigid linker was also synthesized via more complex steps. Although the molecular weight of Mn2-PhDTA2 is lower than that of Mn2-TPA-PhDTA2, their T1 relaxivities are similar, being increased by over 71% compared to the mononuclear Mn-PhDTA. In the presence of serum albumin, the relaxivity of Mn2-PhDTA2 was slightly lower than that of Mn2-TPA-PhDTA2, possibly due to the lower affinity constant. The transmetalation reaction with copper(II) ions confirmed that Mn2-PhDTA2 has an ideal kinetic inertness with a dissociation half-life of approximately 10.4 h under physiological conditions. In the variable-temperature 17O NMR study, both Mn-PhDTA and Mn2-PhDTA2 demonstrated a similar estimated q close to 1, indicating the formation of monohydrated complexes with each manganese(II) ion. In addition, Mn2-PhDTA2 demonstrated a superior contrast enhancement to Mn-PhDTA in in vivo vascular and hepatic MRI and can be rapidly cleared through a dual hepatic and renal excretion pattern. The hepatic uptake mechanism of Mn2-PhDTA2 mediated by SLC39A14 was validated in cellular uptake studies.


Asunto(s)
Medios de Contraste , Hígado , Imagen por Resonancia Magnética , Manganeso , Manganeso/química , Hígado/diagnóstico por imagen , Hígado/metabolismo , Imagen por Resonancia Magnética/métodos , Animales , Medios de Contraste/química , Medios de Contraste/síntesis química , Humanos , Proteínas de Transporte de Catión/metabolismo , Proteínas de Transporte de Catión/química , Ratones , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química
9.
Biomacromolecules ; 25(5): 2740-2748, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38563478

RESUMEN

A self-immolative radiocontrast polymer agent has been newly designed for this study. The polymer agent is composed of a degradable poly(benzyl ether)-based backbone that enables complete and spontaneous depolymerization upon exposure to a specific stimulus, with iodophenyl pendant groups that confer a radiodensity comparable to that of commercial agents. In particular, when incorporated into a biodegradable polycaprolactone matrix, the agent not only reinforces the matrix and provides prolonged radiopacity without leaching but also governs the overall degradation kinetics of the composite under basic aqueous conditions, allowing for X-ray tracking and exhibiting a predictable degradation until the end of its lifespan. Our design would be advanced with various other components to produce synergistic functions and extended for applications in implantable biodegradable devices and theragnostic systems.


Asunto(s)
Medios de Contraste , Poliésteres , Medios de Contraste/química , Medios de Contraste/síntesis química , Poliésteres/química , Poliésteres/síntesis química , Polímeros/química , Rayos X
10.
Biotechnol Appl Biochem ; 71(3): 596-608, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38298147

RESUMEN

The current research article has investigated the synthesis and characterization of novel iron nanoparticles (INPs) from neem and betel leaves extract combination using response surface methodology-central composite design and coated with chitosan-curcumin (CCINPs) as a biocompatible and contrast agent for magnetic resonance imaging (MRI). The coating of INPs with chitosan and curcumin (CCINPs) was carried out using a simple, easy, chemical-free ultrasonication method and characteristics were confirmed by UV-visible (Vis) spectrophotometer (UV-Vis), Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscope, atomic force microscopy, and vibrating sample magnetometer. The biocompatibility of the particles was ensured by conducting hemolytic and cell viability assays. The nanoparticle was found to be nonhemolytic (<5%) up to 150 µg/mL for both INPs and CCINPs. The cell viability was stable (peripheral blood mononuclear cells-PBMCs) till 48 h at 150 µg/mL of INPs and CCINPs. Both the test results produced were found to be biocompatible and additionally, an in vitro MRI study of INPs and CCINPs demonstrated the efficiency of the nanoparticle as a negative contrast agent with enhanced contrast nature in CCINPs. Thus, overall results indicate that the green synthesized chemical-free novel CCINPs could be a potential candidate for a wide range of applications such as MRI, drug delivery, and in magnetic fluid hyperthermia.


Asunto(s)
Medios de Contraste , Tecnología Química Verde , Imagen por Resonancia Magnética , Medios de Contraste/química , Medios de Contraste/síntesis química , Medios de Contraste/farmacología , Humanos , Hierro/química , Curcumina/química , Curcumina/farmacología , Supervivencia Celular/efectos de los fármacos , Nanopartículas del Metal/química , Extractos Vegetales/química , Quitosano/química
11.
J Acoust Soc Am ; 153(4): 2324, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-37092939

RESUMEN

Limited work has been reported on the acoustic and physical characterization of protein-shelled UCAs. This study characterized bovine serum albumin (BSA)-shelled microbubbles filled with perfluorobutane gas, along with SonoVue, a clinically approved contrast agent. Broadband attenuation spectroscopy was performed at room (23 ± 0.5 °C) and physiological (37 ± 0.5 °C) temperatures over the period of 20 min for these agents. Three size distributions of BSA-shelled microbubbles, with mean sizes of 1.86 µm (BSA1), 3.54 µm (BSA2), and 4.24 µm (BSA3) used. Viscous and elastic coefficients for the microbubble shell were assessed by fitting de Jong model to the measured attenuation spectra. Stable cavitation thresholds (SCT) and inertial cavitation thresholds (ICT) were assessed at room and physiological temperatures. At 37 °C, a shift in resonance frequency was observed, and the attenuation coefficient was increased relative to the measurement at room temperature. At physiological temperature, SCT and ICT were lower than the room temperature measurement. The ICT was observed to be higher than SCT at both temperatures. These results enhance our understanding of temperature-dependent properties of protein-shelled UCAs. These findings study may guide the rational design of protein-shelled microbubbles and help choose suitable acoustic parameters for applications in imaging and therapy.


Asunto(s)
Medios de Contraste , Microburbujas , Fosfolípidos , Albúmina Sérica Bovina , Hexafluoruro de Azufre , Ultrasonografía , Albúmina Sérica Bovina/química , Temperatura , Medios de Contraste/síntesis química , Medios de Contraste/química , Fosfolípidos/química , Hexafluoruro de Azufre/química , Acústica , Tamaño de la Partícula
12.
Proc Natl Acad Sci U S A ; 119(29): e2123527119, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35858309

RESUMEN

A promising clinical trial utilizing gold-silica core-shell nanostructures coated with polyethylene glycol (PEG) has been reported for near-infrared (NIR) photothermal therapy (PTT) of prostate cancer. The next critical step for PTT is the visualization of therapeutically relevant nanoshell (NS) concentrations at the tumor site. Here we report the synthesis of PEGylated Gd2O3-mesoporous silica/gold core/shell NSs (Gd2O3-MS NSs) with NIR photothermal properties that also supply sufficient MRI contrast to be visualized at therapeutic doses (≥108 NSs per milliliter). The nanoparticles have r1 relaxivities more than three times larger than those of conventional T1 contrast agents, requiring less concentration of Gd3+ to observe an equivalent signal enhancement in T1-weighted MR images. Furthermore, Gd2O3-MS NS nanoparticles have r2 relaxivities comparable to those of existing T2 contrast agents, observed in agarose phantoms. This highly unusual combination of simultaneous T1 and T2 contrast allows for MRI enhancement through different approaches. As a rudimentary example, we demonstrate T1/T2 ratio MR images with sixfold contrast signal enhancement relative to its T1 MRI and induced temperature increases of 20 to 55 °C under clinical illumination conditions. These nanoparticles facilitate MRI-guided PTT while providing real-time temperature feedback through thermal MRI mapping.


Asunto(s)
Medios de Contraste , Gadolinio , Oro , Imagen por Resonancia Magnética , Nanocáscaras , Terapia Fototérmica , Medios de Contraste/síntesis química , Gadolinio/química , Oro/química , Imagen por Resonancia Magnética/métodos , Nanocáscaras/química , Terapia Fototérmica/métodos , Polietilenglicoles/química , Dióxido de Silicio/química
13.
J Med Chem ; 65(3): 2593-2609, 2022 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-35089713

RESUMEN

Metabotropic glutamate receptor 2 (mGluR2) is a therapeutic target for several neuropsychiatric disorders. An mGluR2 function in etiology could be unveiled by positron emission tomography (PET). In this regard, 5-(2-fluoro-4-[11C]methoxyphenyl)-2,2-dimethyl-3,4-dihydro-2H-pyrano[2,3-b]pyridine-7-carboxamide ([11C]13, [11C]mG2N001), a potent negative allosteric modulator (NAM), was developed to support this endeavor. [11C]13 was synthesized via the O-[11C]methylation of phenol 24 with a high molar activity of 212 ± 76 GBq/µmol (n = 5) and excellent radiochemical purity (>99%). PET imaging of [11C]13 in rats demonstrated its superior brain heterogeneity and reduced accumulation with pretreatment of mGluR2 NAMs, VU6001966 (9) and MNI-137 (26), the extent of which revealed a time-dependent drug effect of the blocking agents. In a nonhuman primate, [11C]13 selectively accumulated in mGluR2-rich regions and resulted in high-contrast brain images. Therefore, [11C]13 is a potential candidate for translational PET imaging of the mGluR2 function.


Asunto(s)
Medios de Contraste/química , Ácidos Picolínicos/química , Piranos/química , Radiofármacos/química , Receptores de Glutamato Metabotrópico/metabolismo , Animales , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Radioisótopos de Carbono , Medios de Contraste/síntesis química , Medios de Contraste/metabolismo , Femenino , Ligandos , Macaca fascicularis , Masculino , Ácidos Picolínicos/síntesis química , Ácidos Picolínicos/metabolismo , Tomografía de Emisión de Positrones , Piranos/síntesis química , Piranos/metabolismo , Radiofármacos/síntesis química , Radiofármacos/metabolismo , Ratas Sprague-Dawley
14.
J Med Chem ; 65(3): 2078-2090, 2022 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-34949094

RESUMEN

Complete excision of the last remaining 1-2% of tumor tissue without collateral damage remains particularly challenging. Herein, we report thiophenthiadiazole (TTD)-derived fluorophores L6-PEGnk (n = 1, 2, 5) as new-generation NIR-II (1000-1700 nm) probes with exceptional nonfouling performance and significantly high fluorescence quantum yields in water. L6-PEG2k can self-assemble into vesicular micelles and exhibited minimal immunogenicity, low binding affinities, ultralong blood circulation (t1/2 = 59.5 h), and a supercontrast ratio in vivo. Most importantly, L6-PEG2k achieved excellent in vivo CT-26 and U87MG tumor targeting and accumulation (>20 d) through intraperitoneal or intravenous injection. A subcutaneous U87MG tumor and orthotopic brain glioma were successfully resected under NIR-II FIGS in our animal model via intraperitoneal injection in an extended time window (48-144 h). This study highlights the potential of using L6-PEG2K as self-assembling molecular probes with long-circulation persistence for routine preoperative tumor assessment and precise intraoperative image-guided resection.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Medios de Contraste/química , Colorantes Fluorescentes/química , Glioma/diagnóstico por imagen , Espectroscopía Infrarroja Corta/métodos , Animales , Neoplasias Encefálicas/terapia , Línea Celular Tumoral , Medios de Contraste/síntesis química , Medios de Contraste/farmacocinética , Diseño de Fármacos , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/farmacocinética , Glioma/terapia , Semivida , Humanos , Ratones , Ratones Endogámicos BALB C , Polietilenglicoles/química , Teoría Cuántica , Cirugía Asistida por Computador , Distribución Tisular , Trasplante Heterólogo
15.
ACS Appl Mater Interfaces ; 13(48): 56923-56930, 2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-34793118

RESUMEN

Silicon particles have garnered attention as promising biomedical probes for hyperpolarized 29Si magnetic resonance imaging and spectroscopy. However, due to the limited levels of hyperpolarization for nanosized silicon particles, microscale silicon particles have primarily been the focus of dynamic nuclear polarization (DNP) applications, including in vivo magnetic resonance imaging (MRI). To address these current challenges, we developed a facile synthetic method for partially 29Si-enriched porous silicon nanoparticles (NPs) (160 nm) and examined their usability in hyperpolarized 29Si MRI agents with enhanced signals in spectroscopy and imaging. Hyperpolarization characteristics, such as the build-up constant, the depolarization time (T1), and the overall enhancement of the 29Si-enriched silicon NPs (10 and 15%), were thoroughly investigated and compared with those of a naturally abundant NP (4.7%). During optimal DNP conditions, the 15% enriched silicon NPs showed more than 16-fold higher enhancements─far beyond the enrichment ratio─than the naturally abundant sample, further improving the signal-to-noise ratio in in vivo 29Si MRI. The 29Si-enriched porous silicon NPs used in this work are potentially capable to serve as drug-delivery vehicles in addition to hyperpolarized 29Si in vivo, further enabling their potential future applicability as a theragnostic platform.


Asunto(s)
Materiales Biomiméticos/química , Medios de Contraste/química , Imagen por Resonancia Magnética , Nanopartículas/química , Miembro Fantasma/diagnóstico por imagen , Silicio/química , Animales , Materiales Biomiméticos/administración & dosificación , Materiales Biomiméticos/síntesis química , Medios de Contraste/administración & dosificación , Medios de Contraste/síntesis química , Isótopos , Masculino , Ensayo de Materiales , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Nanopartículas/administración & dosificación , Tamaño de la Partícula , Porosidad , Silicio/administración & dosificación
16.
J Med Chem ; 64(20): 15250-15261, 2021 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-34661390

RESUMEN

Dysfunctional elastin turnover plays a major role in the progression of atherosclerotic plaques. Failure of tropoelastin cross-linking into mature elastin leads to the accumulation of tropoelastin within the growing plaque, increasing its instability. Here we present Gd4-TESMA, an MRI contrast agent specifically designed for molecular imaging of tropoelastin within plaques. Gd4-TESMA is a tetrameric probe composed of a tropoelastin-binding peptide (the VVGS-peptide) conjugated with four Gd(III)-DOTA-monoamide chelates. It shows a relaxivity per molecule of 34.0 ± 0.8 mM-1 s-1 (20 MHz, 298 K, pH 7.2), a good binding affinity to tropoelastin (KD = 41 ± 12 µM), and a serum half-life longer than 2 h. Gd4-TESMA accumulates specifically in atherosclerotic plaques in the ApoE-/- murine model of plaque progression, with 2 h persistence of contrast enhancement. As compared to the monomeric counterpart (Gd-TESMA), the tetrameric Gd4-TESMA probe shows a clear advantage regarding both sensitivity and imaging time window, allowing for a better characterization of atherosclerotic plaques.


Asunto(s)
Aterosclerosis/metabolismo , Medios de Contraste/química , Elastina/metabolismo , Gadolinio/química , Imagen por Resonancia Magnética , Tropoelastina/análisis , Animales , Medios de Contraste/síntesis química , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Estructura Molecular , Resonancia por Plasmón de Superficie
17.
Chem Commun (Camb) ; 57(89): 11799-11802, 2021 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-34676854

RESUMEN

Here, the synthesis of sub-micron MMnF3 (M = Na or K) particles by a rapid microwave-assisted approach is reported. Adjustment of the Na+-to-Mn2+ ratio in the reaction mixture yielded tuneable morphologies, i.e., rods, ribbons, and plates. Relaxometric results indicated that poly(acrylic acid)-capped MMnF3 particles exhibited characteristic magnetic properties, which endows them with potential T1-weighted contrast agent capabilities.


Asunto(s)
Medios de Contraste/síntesis química , Fluoruros/síntesis química , Compuestos de Manganeso/síntesis química , Nanotubos/química , Fenómenos Magnéticos , Microondas
18.
J Mater Chem B ; 9(43): 9055-9066, 2021 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-34673872

RESUMEN

Single-modal magnetic resonance imaging (MRI) contrast agents sometimes cause signal confusion in clinical diagnosis. Utilizing ligands to endow iron oxide nanoparticles (IO NPs) with excellent dual-modal MRI contrast efficiency might be an effective strategy to improve diagnostic accuracy. This work presents the development of a special ligand-assisted one-pot approach for the preparation of super-hydrophilic magnetic NPs with excellent water dispersion, biocompatibility and T1-T2 dual-modal contrast enhancement properties. In addition, the strong binding capacity between the ethylenediamine tetramethylenephosphonic acid (EDTMP) ligand and water molecules induced by the presence of abundant hydrogen bonds significantly improves spin-lattice (T1) and spin-spin (T2) imaging of the IO core. After being modified with the EDTMP ligand, the T2 relaxation rate of the IO core is dramatically increased from 71.78 mM-1 s-1 to 452.38 mM-1 s-1, and a moderate T1 relaxation rate (11.61 mM-1 s-1) is observed simultaneously, implying that the NPs with an average size of 9.7 nm may be potential candidates as high-efficiency T1-T2 MRI contrast agents. This fundamental technique of using super-hydrophilicity ligands to endow IO NPs with dual-modal contrast properties without size change and damage in the T2 contrast effect may provide a useful strategy to facilitate the application of magnetic NPs in the field of medical diagnosis.


Asunto(s)
Materiales Biocompatibles/química , Medios de Contraste/química , Nanopartículas Magnéticas de Óxido de Hierro/química , Imagen por Resonancia Magnética , Compuestos Organofosforados/química , Agua/química , Células 3T3 , Animales , Materiales Biocompatibles/administración & dosificación , Materiales Biocompatibles/síntesis química , Medios de Contraste/administración & dosificación , Medios de Contraste/síntesis química , Hemólisis , Ligandos , Nanopartículas Magnéticas de Óxido de Hierro/administración & dosificación , Ratones , Compuestos Organofosforados/administración & dosificación , Tamaño de la Partícula , Propiedades de Superficie
19.
J Am Chem Soc ; 143(42): 17677-17689, 2021 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-34637304

RESUMEN

Modern polymer science suffers from the curse of multidimensionality. The large chemical space imposed by including combinations of monomers into a statistical copolymer overwhelms polymer synthesis and characterization technology and limits the ability to systematically study structure-property relationships. To tackle this challenge in the context of 19F magnetic resonance imaging (MRI) agents, we pursued a computer-guided materials discovery approach that combines synergistic innovations in automated flow synthesis and machine learning (ML) method development. A software-controlled, continuous polymer synthesis platform was developed to enable iterative experimental-computational cycles that resulted in the synthesis of 397 unique copolymer compositions within a six-variable compositional space. The nonintuitive design criteria identified by ML, which were accomplished by exploring <0.9% of the overall compositional space, lead to the identification of >10 copolymer compositions that outperformed state-of-the-art materials.


Asunto(s)
Medios de Contraste/química , Polímeros/química , Medios de Contraste/síntesis química , Flúor/química , Aprendizaje Automático , Imagen por Resonancia Magnética , Polímeros/síntesis química , Programas Informáticos , Solubilidad
20.
ACS Appl Mater Interfaces ; 13(36): 42473-42485, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34474563

RESUMEN

The particular characteristics of hypoxia, immune suppression in the tumor microenvironment, and the lack of accurate imaging guidance lead to the limited effects of stereotactic body radiotherapy (SBRT) in reducing the recurrence rate and mortality of hepatocellular carcinoma (HCC). This research developed a novel theranostic agent based on Bi/Se nanoparticles (NPs), synthesized by a simple reduction reaction method for in vivo CT image-guided SBRT sensitization in mice. After loading Lenvatinib (Len), the obtained Bi/Se-Len NPs had excellent performance in reversing hypoxia and the immune suppression status of HCC. In vivo CT imaging results uncovered that the radiotherapy (RT) area could be accurately labeled after the injection of Bi/Se-Len NPs. Under Len's unique and robust properties, in vivo treatment was then carried out upon injection of Bi/Se-Len NPs, achieving excellent RT sensitization effects in a mouse HCC model. Comprehensive tests and histological stains revealed that Bi/Se-Len NPs could reshape and normalize tumor blood vessels, reduce the hypoxic situation of the tumor, and upregulate tumor-infiltrating CD4+ and CD8+ T lymphocytes around the tumors. Our work highlights an excellent proposal of Bi/Se-Len NPs as theranostic nanoparticles for image-guided HCC radiotherapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Medios de Contraste/uso terapéutico , Neoplasias Hepáticas/tratamiento farmacológico , Nanopartículas del Metal/uso terapéutico , Microambiente Tumoral/efectos de los fármacos , Animales , Bismuto/química , Bismuto/uso terapéutico , Bismuto/toxicidad , Vasos Sanguíneos/efectos de los fármacos , Carcinoma Hepatocelular/diagnóstico por imagen , Línea Celular Tumoral , Medios de Contraste/síntesis química , Medios de Contraste/toxicidad , Portadores de Fármacos/síntesis química , Portadores de Fármacos/uso terapéutico , Portadores de Fármacos/toxicidad , Femenino , Humanos , Hipoxia/tratamiento farmacológico , Neoplasias Hepáticas/diagnóstico por imagen , Linfocitos/efectos de los fármacos , Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Ratones Endogámicos BALB C , Compuestos de Fenilurea/uso terapéutico , Medicina de Precisión , Puntos Cuánticos/química , Puntos Cuánticos/uso terapéutico , Puntos Cuánticos/toxicidad , Quinolinas/uso terapéutico , Fármacos Sensibilizantes a Radiaciones/síntesis química , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Fármacos Sensibilizantes a Radiaciones/toxicidad , Radiocirugia , Selenio/química , Selenio/uso terapéutico , Selenio/toxicidad , Tomografía Computarizada por Rayos X
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