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1.
Cureus ; 16(7): e64490, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39139334

RESUMO

White spot lesions (WSLs) and demineralized enamel surfaces are common dental issues that can lead to further complications if untreated. The potential of various remineralizing agents has been extensively studied, but the efficacy of polyamidoamine (PAMAM) dendrimers in promoting enamel remineralization remains to be fully elucidated. This systematic review aims to evaluate the remineralizing potential of PAMAM on WSLs and demineralized enamel surfaces. To identify relevant studies, a comprehensive literature search was conducted across multiple databases, including PubMed, Scopus, and Cochrane Library. Inclusion criteria comprised in vitro and in vivo studies that assessed the effects of PAMAM on WSLs or demineralized enamel. Data extraction and quality assessment were performed independently by two reviewers. The primary outcomes measured were changes in enamel microhardness, surface morphology, and mineral content. Five studies met the inclusion criteria, comprising in vitro studies. The results indicated that PAMAM demonstrated a significant remineralizing effect on demineralized enamel surfaces, as evidenced by increased microhardness and improved surface morphology. The studies varied in their methodological approaches but collectively supported the potential of PAMAM in enamel remineralization. PAMAM dendrimers exhibit promising remineralizing properties for treating WSLs and demineralized enamel surfaces.

2.
Adv Healthc Mater ; : e2401462, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39101311

RESUMO

The development of new multi-target combination treatment strategies to tackle ischemic stroke (IS) remains to be challenging. Herein, a proof-of-concept demonstration of an advanced nanomedicine formulation composed of macrophage membrane (MM)-camouflaged phosphorous dendrimer (termed as AK137)/fibronectin (FN) nanocomplexes (NCs) loaded with antioxidant edaravone (EDV) to modulate both microglia and neurons for effective IS therapy is showcased. The created MM@AK137-FN/EDV (M@A-F/E) NCs with a mean size of 260 nm possess good colloidal stability, sustained EDV release kinetics, and desired cytocompatibility. By virtue of MM decoration, the M@A-F/E NCs can cross blood-brain barrier, act on microglia to exert the anti-inflammatory (AK137 and FN) and antioxidative (FN and EDV) effects in vitro for oxidative stress alleviation, microglia M2 polarization, and reduction of pro-inflammatory cytokine secretion, and act on neuron cells to be anti-apoptotic. In a transient middle cerebral artery occlusion rat model, the developed M@A-F/E NCs can exert enhanced antioxidant/anti-inflammatory/anti-apoptotic therapeutic effects to comprehensively regulate the brain microenvironment and promote vascular regeneration to collaboratively restore the blood flow after ischemia-reperfusion. The designed MM-coated NCs composed of all-active ingredients of phosphorous dendrimers, FN, and EDV that can fully regulate the brain inflammatory microenvironment may expand their application scope in other neurodegenerative diseases.

3.
Angew Chem Int Ed Engl ; : e202412720, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39082148

RESUMO

Thermally activated delayed fluorescence (TADF) emitters with a high horizontal orientation are highly essential for improving the external quantum efficiency (EQE) of organic light-emitting diodes; however, pivotal molecular design strategies to improve the horizontal orientation of solution processable TADF emitters are still scarce and challenging. Herein, a phenyl bridge is adopted to connect the double TADF units, and a dimerized TADF dendrimer, D4CzBNPh-SF, is successfully constructed. Compared to counterpart with single TADF unit, the proof-of-the-concept molecule not only exhibits an improved horizontal dipole ratio (78%) due to the π-delocalization-induced extended molecular conjugation, but also displays a faster reversed intersystem crossing rate constant (6.08×106 s-1) and a high photoluminescence quantum yield of 95% in neat film. Consequently, the non-doped solution-processed device with D4CzBNPh-SF as the emitter, achieves an ultra-high maximum EQE of 32.6%, which remains at 26.6% under a luminance of 1000 cd/m2. Furthermore, using D4CzBNPh-SF as a sensitizer, the TADF-sensitized fluorescence device exhibits a high maximum EQE of 30.7% at a luminance of 575 cd/m2 and a full width at half maximum of 36 nm.

4.
Polymers (Basel) ; 16(14)2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39065339

RESUMO

Glioma is the most common primary intracranial tumor, which is formed by the malignant transformation of glial cells in the brain and spinal cord. It has the characteristics of high incidence, high recurrence rate, high mortality and low cure rate. The treatments for glioma include surgical removal, chemotherapy and radiotherapy. Due to the obstruction of the biological barrier of brain tissue, it is difficult to achieve the desired therapeutic effects. To address the limitations imposed by the brain's natural barriers and enhance the treatment efficacy, researchers have effectively used brain-targeted drug delivery systems (DDSs) in glioma therapy. Polyamidoamine (PAMAM) dendrimers, as branched macromolecular architectures, represent promising candidates for studies in glioma therapy. This review focuses on PAMAM-based DDSs in the treatment of glioma, highlighting their physicochemical characteristics, structural properties as well as an overview of the toxicity and safety profiles.

5.
Res Sq ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39041040

RESUMO

Current clinical strategies for the delivery of pulmonary therapeutics to the lung are primarily targeted to the upper portions of the airways. However, targeted delivery to the lower regions of the lung is necessary for the treatment of parenchymal lung injury and disease. Here, we have developed an mRNA therapeutic for the lower lung using one-component Ionizable Amphiphilic Janus Dendrimers (IAJDs) as a delivery vehicle. We deliver an anti-inflammatory cytokine mRNA, transforming growth factor-beta (TGF-ß), to produce transient protein expression in the lower regions of the lung. This study highlights IAJD's potential for precise, effective, and safe delivery of TGF-ß mRNA to the lung. This delivery system offers a promising approach for targeting therapeutics to the specific tissues, a strategy necessary to fill the current clinical gap in treating parenchymal lung injury and disease.

6.
Int J Mol Sci ; 25(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-39000306

RESUMO

The unique structure of G4.0 PAMAM dendrimers allows a drug to be enclosed in internal spaces or immobilized on the surface. In the conducted research, the conditions for the formation of the active G4.0 PAMAM complex with doxorubicin hydrochloride (DOX) were optimized. The physicochemical properties of the system were monitored using dynamic light scattering (DLS), circular dichroism (CD), and fluorescence spectroscopy. The Quartz Crystal Microbalance with Dissipation Monitoring (QCM-D) method was chosen to determine the preferential conditions for the complex formation. The highest binding efficiency of the drug to the cationic dendrimer was observed under basic conditions when the DOX molecule was deprotonated. The decrease in the zeta potential of the complex confirms that DOX immobilizes through electrostatic interaction with the carrier's surface amine groups. The binding constants were determined from the fluorescence quenching of the DOX molecule in the presence of G4.0 PAMAM. The two-fold way of binding doxorubicin in the structure of dendrimers was visible in the Isothermal calorimetry (ITC) isotherm. Fluorescence spectra and release curves identified the reversible binding of DOX to the nanocarrier. Among the selected cancer cells, the most promising anticancer activity of the G4.0-DOX complex was observed in A375 malignant melanoma cells. Moreover, the preferred intracellular location of the complexes concerning the free drug was found, which is essential from a therapeutic point of view.


Assuntos
Dendrímeros , Doxorrubicina , Dendrímeros/química , Doxorrubicina/química , Doxorrubicina/farmacologia , Humanos , Linhagem Celular Tumoral , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Sobrevivência Celular/efeitos dos fármacos
7.
Top Curr Chem (Cham) ; 382(3): 27, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39033235

RESUMO

Supramolecular polymers are polymeric materials of monomeric fragments, held jointly by reversible and directional non-covalent interactions such as multiple hydrogen-bonding, charge transfer effects, host-guest interactions, metal coordination, and aromatic stacking. This review article on the Hamilton-based supramolecular polymers aims to shed light on the molecular recognition achievements by the Hamilton-based polymeric systems, evaluate Hamilton receptor's future prospects, and capitalize its potential applications in supramolecular chemistry. To the best of our knowledge, this is the first elaborative and sole manuscript in which polymeric Hamilton receptors are being exposed in detail. The first portion of this manuscript is related to the importance and urgency of polymers along with the historic background of Hamilton receptors. The middle section discloses the potential applications of Hamilton-type receptors in various fields, e.g., dendrimers, mechanically polymeric rotaxanes, and self-assemblies. The final section of the manuscript discloses the future aspects and the importance of novel polymer-based Hamilton-type receptors in the modern era. We believe that this first review in this emerging yet immature field will be useful to inspire scientists around the world to find the unseen future prospects, thereby boosting the field related to this valued artificial receptor in the province of supramolecular chemistry and also in other domains of scientific fields and technology, as well.


Assuntos
Polímeros , Polímeros/química , Substâncias Macromoleculares/química , Rotaxanos/química , Dendrímeros/química , Estrutura Molecular , Receptores Artificiais/química , Receptores Artificiais/metabolismo , Ligação de Hidrogênio
8.
J Pharm Pharmacol ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39045860

RESUMO

OBJECTIVES: Poly(amidoamine) dendrimers have been widely investigated as potential nanomaterials that can enhance the skin permeation of topically applied drugs. This article reviews the studies that have used dendrimers as penetration enhancers and examines the mechanisms by which enhancement is claimed. KEY FINDINGS: A wide range of studies have demonstrated that, in certain circumstances and for certain drugs, the incorporation of dendrimers into a topically applied formulation can significantly increase the amount of drug passing into and through the skin. In some cases, dendrimers offered little or no enhancement of skin permeation, suggesting that the drug-dendrimer interaction and the selection of a specific dendrimer were central to ensuring optimal enhancement of skin permeation. Significant interactions between dendrimers and other formulation components were also reported in some cases. SUMMARY: Dendrimers offer substantial potential for enhancing drug delivery into and across the skin, putatively by mechanisms that include occlusion and changes to surface tension. However, most of these studies are conducted in vitro and limited progress has been made beyond such laboratory studies, some of which are conducted using membranes of limited relevance to humans, such as rodent skin. Thus, the outcomes and claims of such studies should be treated with caution.

9.
Cell Biochem Biophys ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39023679

RESUMO

The escalating global threat of antibiotic resistance underscores the urgent need for innovative antimicrobial strategies. This review explores the cutting-edge applications of nanotechnology in combating bacterial infections, addressing a critical healthcare challenge. We critically assess the antimicrobial properties and mechanisms of diverse nanoparticle systems, including liposomes, polymeric micelles, solid lipid nanoparticles, dendrimers, zinc oxide, silver, and gold nanoparticles, as well as nanoencapsulated essential oils. These nanomaterials offer distinct advantages, such as enhanced drug delivery, improved bioavailability, and efficacy against antibiotic-resistant strains. Recent advancements in nanoparticle synthesis, functionalization, and their synergistic interactions with conventional antibiotics are highlighted. The review emphasizes biocompatibility considerations, stressing the need for rigorous safety assessments in nanomaterial applications. By synthesizing current knowledge and identifying emerging trends, this review provides crucial insights for researchers and clinicians aiming to leverage nanotechnology for next-generation antimicrobial therapies. The integration of nanotechnology represents a promising frontier in combating infectious diseases, underscoring the timeliness and imperative of this comprehensive analysis.

10.
ACS Appl Mater Interfaces ; 16(32): 41907-41915, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39083440

RESUMO

Polyamidoamine (PAMAM) dendrimers are nanoparticles that have a wide scope in the field of biomedicine. Previous evidence shows that the generation 4 (G4) dendrimers with a 100% amine surface (G4-NH2) are highly toxic to cells in vitro and in vivo due to their positively charged amine groups. To reduce the toxicity, we modified the surface of the dendrimers to have more neutral functional groups, with 10% of the surface covered with -NH2 and 90% of the surface covered with hydroxyl groups (-OH; G4-90/10). Our previous in vitro data show that these modified dendrimers are taken up by cells, neurons, and different types of stem cells in vitro and neurons and glial cells in vivo. The toxicity assay shows that these modified dendrimers are less toxic compared with G4-NH2 dendrimers. Moreover, prolonged dendrimer exposure (G1-90/10 and G4-90/10), up to 3 weeks following unilateral intrastriatal injections into the striatum of mice, showed that dendrimers have the tendency to migrate within the brain via corpus callosum at different rates depending on their size. We also found that there is a difference in migration between the G1 and G4 dendrimers based on their size differences. The G4 dendrimers migrate in the anterior and posterior directions as well as more laterally from the site of injection in the striatum compared to the G1 dendrimers. Moreover, the G4 dendrimers have unique projections from the site of injection to the cortical areas.


Assuntos
Dendrímeros , Dendrímeros/química , Dendrímeros/toxicidade , Animais , Camundongos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Masculino , Propriedades de Superfície
11.
Bioorg Chem ; 150: 107567, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38936047

RESUMO

Di-branched and tetra-branched versions of a previously reported analogue of the lipopeptide battacin were successfully synthesised using thiol-maleimide click and 1, 2, 3-triazole click chemistry. Antimicrobial studies against drug resistant clinical isolates of Escherichia coli (ESBL E. coli Ctx-M14), Pseudomonas aeruginosa (P. aeruginosa Q502), and Methicillin resistant Staphylococcus aureus (MRSA ATCC 33593), as well as clinically isolated Acinetobacter baumannii (A. baumannii ATCC 19606), and P. aeruginosa (ATCC 27853), revealed that the dendrimeric peptides have antimicrobial activity in the low micromolar range (0.5 -- 4 µM) which was 10 times more potent than the monomer peptides. Under high salt concentrations (150 mM NaCl, 2 mM MgCl2, and 2.5 mM CaCl2) the di-branched lipopeptides retained their antimicrobial activity while the monomer peptides were not active (>100 µM). The di-branched triazole click lipopeptide, Peptide 12, was membrane lytic, showed faster killing kinetics, and exhibited antibiofilm activity against A. baumannii and MRSA and eradicated > 85 % preformed biofilms at low micromolar concentrations. The di-branched analogues were > 30-fold potent than the monomers against Candida albicans. Peptide 12 was not haemolytic (HC10 = 932.12 µM) and showed up to 40-fold higher selectivity against bacteria and fungi than the monomer peptide. Peptide 12 exhibited strong proteolytic stability (>80 % not degraded) in rat serum over 24 h whereas > 95 % of the thiol-maleimide analogue (Peptide 10) was degraded. The tetra-branched peptides showed comparable antibacterial potency to the di-branched analogues. These findings indicate that dual branching using triazole click chemistry is a promising strategy to improve the antimicrobial activity and proteolytic stability of battacin based lipopeptides. The information gathered can be used to build effective antimicrobial dendrimeric peptides as new peptide antibiotics.


Assuntos
Antibacterianos , Dendrímeros , Lipopeptídeos , Testes de Sensibilidade Microbiana , Humanos , Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Química Click , Dendrímeros/química , Dendrímeros/farmacologia , Dendrímeros/síntese química , Relação Dose-Resposta a Droga , Escherichia coli/efeitos dos fármacos , Lipopeptídeos/farmacologia , Lipopeptídeos/síntese química , Lipopeptídeos/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Estrutura Molecular , Pseudomonas aeruginosa/efeitos dos fármacos , Relação Estrutura-Atividade , Peptídeos/química , Peptídeos/farmacologia
12.
Adv Sci (Weinh) ; 11(30): e2401935, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38837626

RESUMO

Lipidic nanocarriers are a broad class of lipid-based vectors with proven potential for packaging and delivering emerging nucleic acid therapeutics. An important early step in the clinical development cycle is large-scale screening of diverse formulation libraries to assess particle quality and payload delivery efficiency. Due to the size of the screening space, this process can be both costly and time-consuming. To address this, computational models capable of predicting clinically relevant physio-chemical properties of dendrimer-lipid nanocarriers, along with their mRNA payload delivery efficiency in human cells are developed. The models are then deployed on a large theoretical nanocarrier pool consisting of over 4.5 million formulations. Top predictions are synthesised for validation using cell-based assays, leading to the discovery of a high quality, high performing, candidate. The methods reported here enable rapid, high-throughput, in silico pre-screening for high-quality candidates, and have great potential to reduce the cost and time required to bring mRNA therapies to the clinic.


Assuntos
Simulação por Computador , RNA Mensageiro , RNA Mensageiro/genética , Humanos , Nanopartículas/química , Lipídeos/química , Dendrímeros/química , Portadores de Fármacos/química
13.
Int J Pharm ; 661: 124389, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38942185

RESUMO

We have recently witnessed that considerable progresses have been made in the rapid detection and appropriate treatments of COVID-19, but still this virus remains one of the main targets of world research. Based on the knowledge of the complex mechanism of viral infection we designed peptide-dendrimer inhibitors of SARS-CoV-2with the aim to block cell infection through interfering with the host-pathogen interactions. We used two different strategies: i) the first one aims at hindering the virus anchorage to the human cell; ii) the second -strategy points to interfere with the mechanism of virus-cell membrane fusion. We propose the use of different nanosized carriers, formed by several carbosilane dendritic wedges to deliver two different peptides designed to inhibit host interaction or virus entry. The antiviral activity of the peptide-dendrimers, as well as of free peptides and free dendrimers was evaluated through the use of SARS-CoV-2 pseudotyped lentivirus. The results obtained show that peptides designed to block host-pathogen interaction represent a valuable strategy for viral inhibition.


Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , Dendrímeros , Peptídeos , SARS-CoV-2 , Dendrímeros/química , Dendrímeros/farmacologia , Humanos , SARS-CoV-2/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/química , Peptídeos/química , Peptídeos/farmacologia , Internalização do Vírus/efeitos dos fármacos , Desenho de Fármacos , COVID-19/virologia , Silanos/química , Silanos/farmacologia , Interações Hospedeiro-Patógeno
14.
Int J Mol Sci ; 25(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38892071

RESUMO

Peptides displaying antimicrobial properties are being regarded as useful tools to evade and combat antimicrobial resistance, a major public health challenge. Here we have addressed dendrimers, attractive molecules in pharmaceutical innovation and development displaying broad biological activity. Triazine-based dendrimers were fully synthesized in the solid phase, and their antimicrobial activity and some insights into their mechanisms of action were explored. Triazine is present in a large number of compounds with highly diverse biological targets with broad biological activities and could be an excellent branching unit to accommodate peptides. Our results show that the novel peptide dendrimers synthesized have remarkable antimicrobial activity against Gram-negative bacteria (E. coli and P. aeruginosa) and suggest that they may be useful in neutralizing the effect of efflux machinery on resistance.


Assuntos
Dendrímeros , Escherichia coli , Testes de Sensibilidade Microbiana , Triazinas , Dendrímeros/química , Dendrímeros/síntese química , Dendrímeros/farmacologia , Triazinas/química , Triazinas/farmacologia , Triazinas/síntese química , Escherichia coli/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Peptídeos Antimicrobianos/química , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/síntese química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/síntese química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/síntese química
15.
Alzheimers Res Ther ; 16(1): 101, 2024 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711159

RESUMO

BACKGROUND: In Alzheimer's disease (AD), microglia surround extracellular plaques and mount a sustained inflammatory response, contributing to the pathogenesis of the disease. Identifying approaches to specifically target plaque-associated microglia (PAMs) without interfering in the homeostatic functions of non-plaque associated microglia would afford a powerful tool and potential therapeutic avenue. METHODS: Here, we demonstrated that a systemically administered nanomedicine, hydroxyl dendrimers (HDs), can cross the blood brain barrier and are preferentially taken up by PAMs in a mouse model of AD. As proof of principle, to demonstrate biological effects in PAM function, we treated the 5xFAD mouse model of amyloidosis for 4 weeks via systemic administration (ip, 2x weekly) of HDs conjugated to a colony stimulating factor-1 receptor (CSF1R) inhibitor (D-45113). RESULTS: Treatment resulted in significant reductions in amyloid-beta (Aß) and a stark reduction in the number of microglia and microglia-plaque association in the subiculum and somatosensory cortex, as well as a downregulation in microglial, inflammatory, and synaptic gene expression compared to vehicle treated 5xFAD mice. CONCLUSIONS: This study demonstrates that systemic administration of a dendranib may be utilized to target and modulate PAMs.


Assuntos
Doença de Alzheimer , Dendrímeros , Modelos Animais de Doenças , Camundongos Transgênicos , Microglia , Placa Amiloide , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Placa Amiloide/tratamento farmacológico , Placa Amiloide/patologia , Camundongos , Peptídeos beta-Amiloides/metabolismo , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Humanos
16.
Chempluschem ; : e202400114, 2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38797707

RESUMO

Self-assembly of designed molecules has enabled the construction of a variety of functional nanostructures. Specifically, adaptable self-assembly has demonstrated several advantageous features for smart materials. Here, we demonstrate that an α-helical coiled coil conjugated with a dendrimer can adapt to spatial restriction due to the strong steric repulsion between dendrimer chains. The adaptable transformation of a tetrameric coiled coil to a trimeric coiled coil can be confirmed using analytical ultracentrifugation upon conjugation of the dendrimer to the coiled coil-forming building block. Interestingly, circular dichroism spectroscopy analysis of the dendrimer conjugate revealed an unconventional trend: the multimerization of the coiled coil is inversely dependent on concentration. This result implies that the spatial crowding between the bulky dendritic chains is significantly stronger than that between linear chains, thereby affecting the overall assembly process. We further illustrated the application potential by decorating the surface of gold nanorods (AuNRs) with the adaptable coiled coil. The dendrimer-coiled coil peptide conjugate can be utilized to fabricate organic-inorganic nanohybrids with enhanced colloidal and thermal stabilities. This study demonstrates that the coiled coil can engage in the adaptable mode of self-assembly with the potential to form dynamic peptide-based materials.

17.
Gels ; 10(5)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38786209

RESUMO

This work reports on a novel family of silver metallogels based on discrete coordination complexes. Structurally, they consist of dendrimers containing a trinuclear silver metallacycle at the core, with the general formula [M(µ-pz)]3, and poly(benzyl)ether branched structures with different numbers or terminal alkoxy chains at the periphery. These silver metallodendrimers are able to gel low-polarity solvents such as dodecane or cyclohexane, giving rise to luminescent organogels at room temperature with the property of aggregation-induced emission (AIE). This property means that in solution or the sol state, they are weak emitters, but in the gel state, luminescence is considerably increased. In this particular case, they exhibit blue luminescence. Two different dendritic scaffolds have been studied, finding significant differences in solubility, gel formation and dependence of luminescence on temperature. The results show that properly tailored silver gelators can show luminescence in the gel state.

18.
EJNMMI Radiopharm Chem ; 9(1): 37, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38703297

RESUMO

BACKGROUND: Radiation nanomedicines are nanoparticles labeled with radionuclides that emit α- or ß-particles or Auger electrons for cancer treatment. We describe here our 15 years scientific journey studying locally-administered radiation nanomedicines for cancer treatment. We further present a view of the radiation nanomedicine landscape by reviewing research reported by other groups. MAIN BODY: Gold nanoparticles were studied initially for radiosensitization of breast cancer to X-radiation therapy. These nanoparticles were labeled with 111In to assess their biodistribution after intratumoural vs. intravenous injection. Intravenous injection was limited by high liver and spleen uptake and low tumour uptake, while intratumoural injection provided high tumour uptake but low normal tissue uptake. Further, [111In]In-labeled gold nanoparticles modified with trastuzumab and injected iintratumourally exhibited strong tumour growth inhibition in mice with subcutaneous HER2-positive human breast cancer xenografts. In subsequent studies, strong tumour growth inhibition in mice was achieved without normal tissue toxicity in mice with human breast cancer xenografts injected intratumourally with gold nanoparticles labeled with ß-particle emitting 177Lu and modified with panitumumab or trastuzumab to specifically bind EGFR or HER2, respectively. A nanoparticle depot (nanodepot) was designed to incorporate and deliver radiolabeled gold nanoparticles to tumours using brachytherapy needle insertion techniques. Treatment of mice with s.c. 4T1 murine mammary carcinoma tumours with a nanodepot incorporating [90Y]Y-labeled gold nanoparticles inserted into one tumour arrested tumour growth and caused an abscopal growth-inhibitory effect on a distant second tumour. Convection-enhanced delivery of [177Lu]Lu-AuNPs to orthotopic human glioblastoma multiforme (GBM) tumours in mice arrested tumour growth without normal tissue toxicity. Other groups have explored radiation nanomedicines for cancer treatment in preclinical animal tumour xenograft models using gold nanoparticles, liposomes, block copolymer micelles, dendrimers, carbon nanotubes, cellulose nanocrystals or iron oxide nanoparticles. These nanoparticles were labeled with radionuclides emitting Auger electrons (111In, 99mTc, 125I, 103Pd, 193mPt, 195mPt), ß-particles (177Lu, 186Re, 188Re, 90Y, 198Au, 131I) or α-particles (225Ac, 213Bi, 212Pb, 211At, 223Ra). These studies employed intravenous or intratumoural injection or convection enhanced delivery. Local administration of these radiation nanomedicines was most effective and minimized normal tissue toxicity. CONCLUSIONS: Radiation nanomedicines have shown great promise for treating cancer in preclinical studies. Local intratumoural administration avoids sequestration by the liver and spleen and is most effective for treating tumours, while minimizing normal tissue toxicity.

19.
ADMET DMPK ; 12(2): 239-267, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38720923

RESUMO

Background and purpose: Treatments using antimicrobial agents have faced many difficulties as a result of biofilm formation by pathogenic microorganisms. The biofilm matrix formed by these microorganisms prevents antimicrobial agents from penetrating the interior where they can exact their activity effectively. Additionally, extracellular polymeric molecules associated with biofilm surfaces can absorb antimicrobial compounds, lowering their bioavailability. This problem has resulted in the quest for alternative treatment protocols, and the development of nanomaterials and devices through nanotechnology has recently been on the rise. Research approach: The literature on dendrimers was searched for in databases such as Google Scholar, PubMed, and ScienceDirect. Key results: As a nanomaterial, dendrimers have found useful applications as a drug delivery vehicle for antimicrobial agents against biofilm-mediated infections to circumvent these defense mechanisms. The distinctive properties of dendrimers, such as multi-valency, biocompatibility, high water solubility, non-immunogenicity, and biofilm matrix-/cell membrane fusogenicity (ability to merge with intracellular membrane or other proteins), significantly increase the efficacy of antimicrobial agents and reduce the likelihood of recurring infections. Conclusion: This review outlines the current state of dendrimer carriers for biofilm treatments, provides examples of their real-world uses, and examines potential drawbacks.

20.
Artigo em Inglês | MEDLINE | ID: mdl-38716551

RESUMO

Cancer remains a significant global health challenge, necessitating innovative approaches to enhance the efficacy and specificity of therapeutic interventions while minimizing adverse effects on healthy tissues. Nanotechnology has emerged as a promising avenue in cancer treatment, offering novel strategies for targeted drug delivery. Nanoparticles, liposomes, and polymer-based systems have played pivotal roles in revolutionizing cancer therapy. Nanotechnology possesses unique physicochemical properties, enabling efficient encapsulation of therapeutic agents and controlled and prolonged release at tumour sites. Advancement in formulations using nanotechnology has made it possible to make multifunctional systems that respond to the microenvironment of a tumour by releasing payloads in response to changes in pH, temperature, or enzymes. Stimuli-responsive polymers can release drugs in response to external cues, enabling site-specific drug release and minimizing systemic exposure. This review explores recent studies and preclinical trials that show how nanoparticles, liposomes, and polymerbased systems could be used to treat cancer, discussing challenges such as scalability, regulatory approval, and potential toxicity concerns along with patents published recently.

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