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1.
Article in English | MEDLINE | ID: mdl-38846932

ABSTRACT

Using dendron chemistry, we developed stability enhanced, carboxylate surface modified (negatively charged dendron) AuNPs (Au-NCD). Since the carboxylate surface of Au-NCD is optimal for complexation with cisplatin (Pt) moieties, we further synthesized Pt loaded Au-NCD (Au-NCD/Pt) to serve as potential therapeutic anticancer agents. The size distribution, zeta potential and surface plasmon resonance of both Au-NCDs and Au-NCD/Pt were characterized via dynamic light scattering, scanning transmission electron microscopy and ultraviolet-visible spectrophotometry. Surface chemistry, Pt uptake, and Pt release were evaluated using inductively coupled plasma-mass spectrometry and X-ray photoelectron spectroscopy. Colloidal stability in physiological media over a wide pH range (1 to 13) and shelf-life stability (up to 6 months) were also assessed. Finally, the cytotoxicity of both Au-NCD and Au-NCD/Pt to Chinese hamster ovary cells (CHO K1; as a normal cell line) and to human lung epithelial cells (A549; as a cancer cell line) were evaluated. The results of these physicochemical and functional cytotoxicity studies with Au-NCD/Pt demonstrated that the particles exhibited superlative colloidal stability, cisplatin uptake and in vitro anticancer activity despite low amounts of Pt release from the conjugate.

2.
Int J Biol Macromol ; 264(Pt 2): 130729, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38460643

ABSTRACT

Astrocyte elevated gene-1 (AEG-1) oncogene is a notorious and evolving target in a variety of human malignancies including osteosarcoma. The RNA interference (RNAi) has been clinically proven to effectively knock down specific genes. To successfully implement RNAi in vivo, protective vectors are required not only to protect unstable siRNAs from degradation, but also to deliver siRNAs to target cells with controlled release. Here, we synthesized a Zein-poly(l-lysine) dendrons non-viral modular system that enables efficient siRNA-targeted AEG-1 gene silencing in osteosarcoma and encapsulation of antitumor drugs for controlled release. The rational design of the ZDP integrates the non-ionic and low immunogenicity of Zein and the positive charge of the poly(l-lysine) dendrons (DPLL) to encapsulate siRNA and doxorubicin (DOX) payloads via electrostatic complexes and achieve pH-controlled release in a lysosomal acidic microenvironment. Nanocomplexes-directed delivery greatly improves siRNA stability, uptake, and AEG-1 sequence-specific knockdown in 143B cells, with transfection efficiencies comparable to those of commercial lipofectamine but with lower cytotoxicity. This AEG-1-focused RNAi therapy supplemented with chemotherapy inhibited, and was effective in inhibiting the growth in of osteosarcoma xenografts mouse models. The combination therapy is an alternative or combinatorial strategy that can produce durable inhibitory responses in osteosarcoma patients.


Subject(s)
Bone Neoplasms , Dendrimers , Nanoparticles , Osteosarcoma , Zein , Animals , Mice , Humans , Polylysine , Azides , Delayed-Action Preparations , Alkynes , Doxorubicin/pharmacology , Osteosarcoma/drug therapy , Osteosarcoma/genetics , RNA, Small Interfering/metabolism , Bone Neoplasms/drug therapy , Bone Neoplasms/genetics , Cell Line, Tumor , Tumor Microenvironment
3.
Front Cell Infect Microbiol ; 13: 1203991, 2023.
Article in English | MEDLINE | ID: mdl-37886663

ABSTRACT

Introduction: Antimicrobial Resistance is a serious public health problem, which is aggravated by the ability of the microorganisms to form biofilms. Therefore, new therapeutic strategies need to be found, one of them being the use of cationic dendritic systems (dendrimers and dendrons). Methods: The aim of this study is to analyze the in vitro antimicrobial efficacy of six cationic carbosilane (CBS) dendrimers and one dendron with peripheral ammonium groups against multidrug-resistant bacteria, some of them isolated hospital strains, and their biofilms. For this purpose, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), minimum biofilm inhibitory concentration (MBIC) and minimum eradication biofilm concentration (MBEC) studies were carried out. In addition, the cytotoxicity on Hela cells of those compounds that proved to be the most effective was analyzed. Results: All the tested compounds showed in vitro activity against the planktonic forms of methicillin-resistant Staphylococcus aureus and only the dendrimers BDSQ017, BDAC-001 and BDLS-001 and the dendron BDEF-130 against their biofilms. On the other hand, only the dendrimers BDAC 001, BDLS-001 and BDJS-049 and the dendron BDEF-130 were antibacterial in vitro against the planktonic forms of multidrug-resistant Pseudomonas aeruginosa, but they lacked activity against their preformed biofilms. In addition, the dendrimers BDAC-001, BDLS-001 and BDSQ-017 and the dendron BDEF-130 exhibited a good profile of cytotoxicity in vitro. Discussion: Our study demonstrates the possibility of using the four compounds mentioned above as possible topical antimicrobials against the clinical and reference strains of multidrug-resistant bacteria.


Subject(s)
Anti-Infective Agents , Dendrimers , Methicillin-Resistant Staphylococcus aureus , Humans , Dendrimers/pharmacology , HeLa Cells , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/pharmacology , Biofilms , Microbial Sensitivity Tests
4.
Pharmaceutics ; 15(8)2023 Aug 09.
Article in English | MEDLINE | ID: mdl-37631317

ABSTRACT

Dendronized nanoparticles, also called nanoparticle-cored dendrimers, combine the advantages of nanoparticles and dendrimers. These very stable and polyvalent nanoparticles can be used for diverse applications. One such application is drug delivery, because the dendrons can enhance the density of the payload. In this report, we describe the design of multifunctional gold nanoparticles (AuNPs) coated with poly(propylene imine) (PPI) dendrons that contain both prostate cancer active targeting and chemotherapeutic drugs. The PPI dendron is a good candidate for the design of drug delivery vehicles because of its ability to induce a proton sponge effect that will enhance lysosomal escape and intracellular therapeutic delivery. The chemotherapeutic drug used is doxorubicin (DOX), and it was linked to the dendron through a hydrazone acid-sensitive bond. Subsequent acidification of the AuNP system to a pH of 4-5 resulted in the release of 140 DOX drugs per nanoparticles. In addition, the PPI dendron was conjugated via "click" chemistry to an EphA2-targeting antibody fragment that has been shown to target prostate cancer cells. In vitro cell viability assays revealed an IC50 of 0.9 nM for the targeted DOX-bearing AuNPs after 48 h incubation with PC3 cells. These results are very promising upon optimization of the system.

5.
Pharm Nanotechnol ; 2023 Aug 17.
Article in English | MEDLINE | ID: mdl-37592778

ABSTRACT

BACKGROUND: Janus Dendrimer represents a novel class of synthetic nanocarriers. Since it is possible to introduce multiple drugs and target moieties, this helps the designing of new biocompatible forms with pharmacological activities comprised of different drugs with tailor-made functionalities, such as anticancer and nonsteroidal anti-inflammatory, which could improve the anticancer activity with less toxicity. AIMS: This study aimed to determine the anticancer activity of the Janus dendrimers formed by two dendrons. One dendron conjugates with chlorambucil, and the other dendron conjugates with Ibuprofen. METHODS: The cytotoxicity of the drug carriers was determined by the sulforhodamine B (SRB) assay for three cell lines. PC-3 (human prostatic adenocarcinoma), HCT-15 (human colorectal adenocarcinoma), MFC-7 (human breast cancer) and the COS-7 African green monkey kidney (used as a control) cell lines were seeded into 96-well plates at a density of 5x103 cells/well and cultured for 24 h before use. All the obtained compounds were characterized by 1H and 13C NMR one and two dimensions, UV-vis, FTIR, MALDI-TOF, Electrospray mass, and FAB+. Microscopic images were taken in an Inverted microscope Nikon, Diaphot 300, 10x4 in culture medium. RESULTS: Janus dendrimers (G1 and G2) were synthesized via an azide-alkyne click-chemistry reaction attaching on one face dendrons with ibuprofen molecules and, on the other face, attached a chlorambucil-derivative. The IC50 behavior of the conjugates of the first and second generations showed anticancer activity against PC-3, HCT-15, and MFC-7 cell lines. The second generation was more active against PC-3, HCT-15 and MFC-7 with IC50 of 3.8±0.5, 3.0±0.2 and 3.7±1.1 M, respectively Conclusion: The new Janus dendrimers with anticancer chlorambucil and nonsteroidal anti-inflammatory Ibuprofen can improve the anticancer activity of chlorambucil with less toxicity.

6.
Molecules ; 28(14)2023 Jul 21.
Article in English | MEDLINE | ID: mdl-37513445

ABSTRACT

Dendrimers, being highly branched monodispersed macromolecules, predominantly exhibit identical terminal functionalities within their structural framework. Nonetheless, there are instances where the presence of two distinct surface functionalities becomes advantageous for the fulfilment of specific properties. To achieve this objective, one approach involves implementing Janus dendrimers, consisting of two dendrimeric wedges terminated by dissimilar functionalities. The prevalent method for creating these structures involves the synthesis of dendrons that possess a core functionality that complements that of a second dendron, facilitating their coupling to generate the desired dendrimers. In this comprehensive review, various techniques employed in the fabrication of phosphorus-based Janus dendrimers are elucidated, displaying the different coupling methodologies employed between the two units. The advantages of phosphorus dendrimers over classic dendrimers will be shown, as the presence of at least one phosphorus atom in each generation allows for the easy monitoring of reactions and the confirmation of purity through a simple technique such as 31P NMR, as these structures typically exhibit easily interpretable patterns.

7.
Pharmaceutics ; 15(7)2023 Jul 24.
Article in English | MEDLINE | ID: mdl-37514199

ABSTRACT

COST Action CA17140 Cancer Nanomedicine-from the bench to the bedside (Nano2Clinic,) is the first, pan-European interdisciplinary network of representatives from academic institutions and small and medium enterprises including clinical research organizations (CROs) devoted to the development of nanosystems carrying anticancer drugs from their initial design, preclinical testing of efficacy, pharmacokinetics and toxicity to the preparation of detailed protocols needed for the first phase of their clinical studies. By promoting scientific exchanges, technological implementation, and innovative solutions, the action aims at providing a timely instrument to rationalize and focus research efforts at the European level in dealing with the grand challenge of nanomedicine translation in cancer, one of the major and societal-burdening human pathologies. Within CA17140, dendrimers in all their forms (from covalent to self-assembling dendrons) play a vital role as powerful nanotheranostic agents in oncology; therefore, the purpose of this review work is to gather and summarize the major results in the field stemming from collaborative efforts in the framework of the European Nano2Clinic COST Action.

8.
Chem Phys Lipids ; 255: 105314, 2023 09.
Article in English | MEDLINE | ID: mdl-37356611

ABSTRACT

Amphiphilic dendrons represent a relatively novel class of molecules which may show many unique properties suitable for applications in a field of molecular biology and nanomedicine. They were frequently studied as platforms suitable for drug delivery systems as were, e.g. polymersomes or hybrid lipid-polymer nanoparticles. Recently, natural extracellular lipid vesicles (EVs), called exosomes (EXs), were shown to be a promising candidate in drug delivery applications. Formation of hybrid exosome-dendron nanovesicles could bring benefits in their simple conjugation with selective targeting moieties. Unfortunately, the complex architecture of biological membranes, EXs included, makes obstacles in elucidating the important parameters and mechanisms of interaction with the artificial amphiphilic structures. The aim of the presented work was to study the interaction of two types of amphiphilic carbosilane dendritic structures (denoted as DDN-1 and DDN-2) suitable for further modification with streptavidin (DDN-1) or using click-chemistry approach (DDN-2), with selected neutral and negatively charged lipid model membranes, partially mimicking the basic properties of natural EXs biomembranes. To meet the goal, a number of biophysical methods were used for determination of the degree and mechanisms of the interaction. The results showed that the strength of interactions of amphiphilic dendrons with liposomes was related with surface charge of liposomes. Several steps of interactions were disclosed. The initialization step was mainly coupled with amphiphilic dendrons - liposomes surface interaction resulting in destabilization of large self-assembled amphiphilic dendrons structures. Such destabilization was more significant with liposomes of higher negative charge. With increasing concentration of amphiphilic dendrons in a solution the interactions were taking place also in the hydrophobic part of bilayer. Further increase of nanoparticle concentration resulted in a gradual dendritic cluster formation in a lipid bilayer structure. Due to high affinity of amphiphilic dendrons to model lipid bilayers the conclusion can be drawn that they represent promising platforms also for decoration of exosomes or other kinds of natural lipid vehicles. Such organized hybrid dendron-lipid biomembranes may be advantageous for their subsequent post-functionalization with small molecules, large biomacromolecules or polymers suitable for targeted drug-delivery or theranostic applications.


Subject(s)
Dendrimers , Liposomes , Silanes , Dendrimers/chemical synthesis , Dendrimers/chemistry , Silanes/chemistry , Liposomes/chemistry , Membrane Potentials , Anisotropy , Calorimetry , Nanoparticles/chemistry
9.
Polymers (Basel) ; 15(8)2023 Apr 09.
Article in English | MEDLINE | ID: mdl-37111979

ABSTRACT

All activities of our daily life, of the nature surrounding us and of the entire society and its complex economic and political systems are affected by stimuli. Therefore, understanding stimuli-responsive principles in nature, biology, society, and in complex synthetic systems is fundamental to natural and life sciences. This invited Perspective attempts to organize, to the best of our knowledge, for the first time the stimuli-responsive principles of supramolecular organizations emerging from self-assembling and self-organizable dendrons, dendrimers, and dendronized polymers. Definitions of stimulus and stimuli from different fields of science are first discussed. Subsequently, we decided that supramolecular organizations of self-assembling and self-organizable dendrons, dendrimers, and dendronized polymers may fit best in the definition of stimuli from biology. After a brief historical introduction to the discovery and development of conventional and self-assembling and self-organizable dendrons, dendrimers, and dendronized polymers, a classification of stimuli-responsible principles as internal- and external-stimuli was made. Due to the enormous amount of literature on conventional dendrons, dendrimers, and dendronized polymers as well as on their self-assembling and self-organizable systems we decided to discuss stimuli-responsive principles only with examples from our laboratory. We apologize to all contributors to dendrimers and to the readers of this Perspective for this space-limited decision. Even after this decision, restrictions to a limited number of examples were required. In spite of this, we expect that this Perspective will provide a new way of thinking about stimuli in all fields of self-organized complex soft matter.

10.
ACS Appl Mater Interfaces ; 15(10): 13393-13404, 2023 Mar 15.
Article in English | MEDLINE | ID: mdl-36856260

ABSTRACT

A family of first-generation dendrimers containing 3,5-bis(carbazolyl)phenyl dendrons attached to a green emissive fac-tris(2-phenylpyridyl)iridium(III) core were prepared. The solubility of the dendrimers was imparted by the attachment of tert-butyl surface groups to the carbazole moieties. The dendrimers differed in the number of dendrons attached to each ligand (one or two dendrons) as well as the degree of rotational restriction within the dendrons. The densities of the films containing the doubly dendronized materials were higher than those of their mono-dendronized counterparts, with the dendrimer containing two rotationally constrained dendrons per ligand having the highest density at 1.12 ± 0.04 g cm-3. The dendrimers were found to have high photoluminescence quantum yields (PLQYs) in solution of between 80 and 90%, with the doubly dendronized materials having the lower values and a red-shifted emission. The neat film PLQY values of the dendrimers were less than those measured in solution although the relative decrease was smaller for the doubly dendronized materials. The dendrimers were incorporated into solution-processed bilayer organic light-emitting diodes (OLEDs) composed of neat or blend emissive layers and an electron transport layer. The best-performing devices had the dendrimers blended with a host material and external quantum efficiencies as high as 14.0%, which is higher than previously reported results for carbazole-incorporating emissive dendrimers. A feature of the devices containing blends of the doubly dendronized materials was that the maximum efficiency was relatively insensitive to the concentration in the host between 1 and 7 mol %.

11.
Int J Mol Sci ; 24(1)2023 Jan 03.
Article in English | MEDLINE | ID: mdl-36614277

ABSTRACT

The fact that cancer is one of the leading causes of death requires researchers to create new systems of effective treatment for malignant tumors. One promising area is genetic therapy that uses small interfering RNA (siRNA). These molecules are capable of blocking mutant proteins in cells, but require specific systems that will deliver RNA to target cells and successfully release them into the cytoplasm. Dendronized and PEGylated silver nanoparticles as potential vectors for proapoptotic siRNA (siMCL-1) were used here. Using the methods of one-dimensional gel electrophoresis, the zeta potential, dynamic light scattering, and circular dichroism, stable siRNA and AgNP complexes were obtained. Data gathered using multicolor flow cytometry showed that AgNPs are able to deliver (up to 90%) siRNAs efficiently to some types of tumor cells, depending on the degree of PEGylation. Analysis of cell death showed that complexes of some AgNP variations with siMCL-1 lead to ~70% cell death in the populations that uptake these complexes due to apoptosis.


Subject(s)
Dendrimers , Metal Nanoparticles , Nanoparticles , Neoplasms , Humans , RNA, Small Interfering/metabolism , Silver , Polyethylene Glycols
12.
Proc Natl Acad Sci U S A ; 120(5): e2215091120, 2023 01 31.
Article in English | MEDLINE | ID: mdl-36696444

ABSTRACT

A foundational principle of rational vaccinology is that vaccine structure plays a critical role in determining therapeutic efficacy, but in order to establish fundamental, effective, and translatable vaccine design parameters, a highly modular and well-defined platform is required. Herein, we report a DNA dendron vaccine, a molecular nanostructure that consists of an adjuvant DNA strand that splits into multiple DNA branches with a varied number of conjugated peptide antigens that is capable of dendritic cell uptake, immune activation, and potent cancer killing. We leveraged the well-defined architecture and chemical modularity of the DNA dendron to study structure-function relationships that dictate molecular vaccine efficacy, particularly regarding the delivery of immune-activating DNA sequences and antigenic peptides on a single chemical construct. We investigated how adjuvant and antigen placement and number impact dendron cellular uptake and immune activation, in vitro. These parameters also played a significant role in raising a potent and specific immune response against target cancer cells. By gaining this structural understanding of molecular vaccines, DNA dendrons successfully treated a mouse cervical human papillomavirus TC-1 cancer model, in vivo, where the vaccine structure defined its efficacy; the top-performing design effectively reduced tumor burden (<150 mm3 through day 30) and maintained 100% survival through 44 d after tumor inoculation.


Subject(s)
Cancer Vaccines , Dendrimers , Papillomavirus Vaccines , Uterine Cervical Neoplasms , Vaccines, DNA , Animals , Female , Mice , Humans , Dendrimers/pharmacology , Uterine Cervical Neoplasms/prevention & control , DNA , Peptides , Papillomavirus Vaccines/genetics
13.
Chemistry ; 29(5): e202202633, 2023 Jan 24.
Article in English | MEDLINE | ID: mdl-36317813

ABSTRACT

Biorthogonal labelling with fluorescent small molecules is an indispensable tool for diagnostic and biomedical applications. In dye-based 5-ethynyl-2'-deoxyuridine (EdU) cell proliferation assays, augmentation of the fluorescent signal entails an overall enhancement in the sensitivity and quality of the method. To this end, a rapid, divergent synthetic procedure that provides ready-to-click pH-insensitive rhodamine dyes exhibiting outstanding brightness was established. Compared to the shortest available synthesis of related high quantum-yielding rhodamines, two fewer synthetic steps are required. In a head-to-head imaging comparison involving copper(I)-catalyzed azide alkyne cycloaddition reactions with in vitro administered EdU, our new 3,3-difluoroazetidine rhodamine azide outperformed the popular 5-TAMRA-azide, making it among the best available choices when it comes to fluorescent imaging of DNA. In a further exploration of the fluorescence properties of these dyes, a set of bis-MPA dendrons carrying multiple fluorescein or rhodamine units was prepared by branching click chemistry. Fluorescence self-quenching of fluorescein- and rhodamine-functionalized dendrons limited the suitability of the dyes as labels in EdU-based experiments but provided new insights into these effects.


Subject(s)
Dendrimers , Xanthenes , Click Chemistry/methods , Azides/chemistry , Dendrimers/chemistry , Rhodamines/chemistry , Coloring Agents/chemistry , Fluorescein/chemistry , Fluorescent Dyes/chemistry
14.
Adv Mater ; 35(3): e2208277, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36300810

ABSTRACT

Design of effective nanomedicines to modulate multiple immune cells to overcome the immune-suppressive tumor microenvironment is desirable to improve the overall poor clinical outcomes of immunotherapy. Herein, a nanomedicine platform is reported based on chemotherapeutic drug doxorubicin (DOX)-loaded phosphorus dendron micelles (M-G1-TBPNa@DOX, TBP, tyramine bearing two dimethylphosphonate) with inherent immunomodulatory activity for synergistic tumor chemoimmunotherapy. The M-G1-TBPNa@DOX micelles with good stability and a mean particle size of 86.4 nm can deliver DOX to solid tumors to induce significant tumor cell apoptosis and immunogenic cell death (ICD). With the demonstrated intrinsic activity of M-G1-TBPNa that can promote the proliferation of natural killer (NK) cells, the ICD-resulted maturation of dendritic cells of the DOX-loaded micelles, and the combination of anti-PD-L1 antibody, the synergistic modulation of multiple immune cells through NK cell proliferation, recruitment of tumor-infiltrating NK cells and cytotoxic T cells, and decrease of regulatory T cells for effective tumor chemoimmunotherapy with strong antitumor immunity and immune memory effect for effective prevention of lung metastasis are demonstrated. The developed phosphorous dendron micelles may hold great promise to be used as an advanced nanomedicine formulation for synergistic modulation of multiple immune cells through NK cell proliferation for effective chemoimmunotherapy of different tumor types.


Subject(s)
Dendrimers , Neoplasms , Humans , Micelles , Nanomedicine , Neoplasms/drug therapy , Doxorubicin/pharmacology , Doxorubicin/therapeutic use , Immunotherapy/methods , Cell Line, Tumor , Tumor Microenvironment
15.
Sensors (Basel) ; 22(23)2022 Dec 06.
Article in English | MEDLINE | ID: mdl-36502262

ABSTRACT

The aggregation of cytotoxic amyloid peptides (Aß1-42) is widely recognised as the cause of brain tissue degeneration in Alzheimer's disease (AD). Indeed, evidence indicates that the deposition of cytotoxic Aß1-42 plaques formed through the gradual aggregation of Aß1-42 monomers into fibrils determines the onset of AD. Thus, distinct Aß1-42 inhibitors have been developed, and only recently, the use of short linear peptides has shown promising results by either preventing or reversing the process of Aß1-42 aggregation. Among them, the KLVFF peptide sequence, which interacts with the hydrophobic region of Aß16-20, has received widespread attention due to its ability to inhibit fibril formation of full-length Aß1-42. In this study, hyperbranched poly-L-lysine dendrons presenting sixteen KLVFF at their uppermost molecular branches were designed with the aim of providing the KLVFF sequence with a molecular scaffold able to increase its stability and of improving Aß1-42 fibril formation inhibitory effect. These high-purity branched KLVFF were used to functionalise the surface of the metal oxide chip of the optical waveguide lightmode spectroscopy sensor showing the more specific, accurate and rapid measurement of Aß1-42 than that detected by linear KLVFF peptides.


Subject(s)
Alzheimer Disease , Lysine , Humans , Amyloid beta-Peptides/chemistry , Peptide Fragments/chemistry , Amyloid/chemistry , Amyloid/metabolism , Alzheimer Disease/metabolism , Spectrum Analysis
16.
Nanomaterials (Basel) ; 12(22)2022 Nov 16.
Article in English | MEDLINE | ID: mdl-36432312

ABSTRACT

A series of six polybenzylic dendrons with an alkynyl focal point were synthesized for their incorporation to gold nanoparticles. Five of these compounds showed columnar mesomorphism in a wide range of temperatures. These dendrons were reacted with gold nanoparticles stabilized with a combination of a dodecanethiol and 11-azidoundecane-1-thiol. The azido group of the last compound allowed the functionalization of the nanoparticles with the six polybenzylic dendrons by 1,3-dipolar cycloaddition between their alkynyl groups and the terminal azido groups of the thiols. A high efficiency of the cycloaddition process (47-69%) was confirmed by several experimental techniques and no decomposition or aggregation phenomena were detected in the dendron-coated nanoparticles. The involved mechanism and the resulting percentage composition of the final materials are discussed. The results of the ulterior growth of the nanoparticles by thermal treatment are influenced by the size and the shape of the dendron and the temperature of the process. The structures of the final nanoparticles were investigated by TEM, DSC, TGA, NMR and UV-Vis spectroscopy. These nanoparticles do not show liquid crystal properties. However, a melting process between a crystalline and a fluid phase is observed. In the solid phase, the nanomaterials prepared show a short-range interaction between nanoparticles with a 2D local hexagonal order. A near-field effect was observed in the UV-vis spectra by coupling of different surface plasmon resonance bands (SPR) probably due to the short-range interactions. The main novelty of this work lies in the scarcity of previous studies of gold nanoparticles coated with dendrons forming themselves columnar mesophases. Most of the studies reported in the literature deal with gold nanoparticles coated with calamitic mesogens. Additionally, the effect of the thermal treatment, which in a previous paper was shown to increase the mean size of the nanoparticles without increasing their size polydispersity, has been studied in these materials.

17.
Nanomaterials (Basel) ; 12(15)2022 Jul 29.
Article in English | MEDLINE | ID: mdl-35957042

ABSTRACT

Dendronized gold nanoparticles (AuNPs) were synthesized bearing charged peripheral groups. Two novel AB3-type dendrons were synthesized with a thiol group at the focal point followed by their attachment to AuNPs. Dendrons were designed to have nine charged peripheral groups (carboxyl or amine), glycol solubilizing, units and one thiol moiety at the focal point. Both dendrons and all intermediates were synthesized in high yields and characterized by nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS). The amine- and carboxyl-terminated dendrons were used to functionalize gold nanoparticles (AuNPs) previously stabilized with citrate. The nanoparticles' diameters and their colloidal stability were investigated using dynamic light scattering (DLS). The size and morphology of the dendronized AuNPs were evaluated by scanning electron microscopy (SEM), which revealed individual particles with no aggregation after replacement of citrate by the dendrons, in agreement with the DLS data. The absorption spectroscopy reveals a prominent plasmonic band at 560 nm for all AuNPs. The zeta potential further confirmed the expected charged structures of the dendronized AuNPs. Considering all the physical-chemical properties of the charged dendronized AuNPs developed in this work, these AuNPs might be used as a weapon against multi-drug resistant bacterial infections.

18.
Pharmaceutics ; 14(8)2022 Jul 30.
Article in English | MEDLINE | ID: mdl-36015222

ABSTRACT

Drug delivery by dendron-based nanoparticles is widely studied due to their ability to encapsulate or bind different ligands. For medical purposes, it is necessary (even if not sufficient) for these nanostructures to be compatible with blood. We studied the interaction of amphiphilic dendrons with blood samples from healthy volunteers using standard laboratory methods and rheological measurements. We did not observe clinically relevant abnormalities, but we found a concentration-dependent increase in whole blood viscosity, higher in males, presumably due to the formation of aggregates. To characterize the nature of the interactions among blood components and dendrons, we performed experiments on the liposomes and exosomes as models of biological membranes. Based on results obtained using diverse biophysical methods, we conclude that the interactions were of electrostatic nature. Overall, we have confirmed a concentration-dependent effect of dendrons on membrane systems, while the effect of generation was ambiguous. At higher dendron concentrations, the structure of membranes became disturbed, and membranes were prone to forming bigger aggregates, as visualized by SEM. This might have implications for blood flow disturbances when used in vivo. We propose to introduce blood viscosity measurements in early stages of investigation as they can help to optimize drug-like properties of potential drug carriers.

19.
Theranostics ; 12(7): 3407-3419, 2022.
Article in English | MEDLINE | ID: mdl-35547777

ABSTRACT

Rationale: Development of novel nanomedicines to inhibit pro-inflammatory cytokine expression and reactive oxygen species (ROS) generation for anti-inflammatory therapy of acute lung injury (ALI) remains challenging. Here, we present a new nanomedicine platform based on tyramine-bearing two dimethylphosphonate sodium salt (TBP)-modified amphiphilic phosphorus dendron (C11G3) nanomicelles encapsulated with antioxidant drug curcumin (Cur). Methods: C11G3-TBP dendrons were synthesized via divergent synthesis and self-assembled to generate nanomicelles in a water environment to load hydrophobic drug Cur. The created C11G3-TBP@Cur nanomicelles were well characterized and systematically examined in their cytotoxicity, cellular uptake, intracellular ROS elimination, pro-inflammatory cytokine inhibition and alveolar macrophages M2 type repolarization in vitro, and evaluated to assay their anti-inflammatory and antioxidative therapy effects of ALI mice model through pro-inflammatory cytokine expression level in bronchoalveolar lavage fluid and lung tissue, histological analysis and micro-CT imaging detection of lung tissue injury in vivo. Results: The nanomicelles with rigid phosphorous dendron structure enable high-capacity and stable Cur loading. Very strikingly, the drug-free C11G3-TBP micelles exhibit excellent cytocompatibility and intrinsic anti-inflammatory activity through inhibition of nuclear transcription factor-kappa B, thus causing repolarization of alveolar macrophages from M1 type to anti-inflammatory M2 type. Taken together with the strong ROS scavenging property of the encapsulated Cur, the developed nanomicelles enable effective therapy of inflammatory alveolar macrophages in vitro and an ALI mouse model in vivo after atomization administration. Conclusion: The created phosphorus dendron nanomicelles can be developed as a general nanomedicine platform for combination anti-inflammatory and antioxidative therapy of inflammatory diseases.


Subject(s)
Acute Lung Injury , Curcumin , Dendrimers , Acute Lung Injury/drug therapy , Acute Lung Injury/pathology , Animals , Anti-Inflammatory Agents/therapeutic use , Antioxidants/pharmacology , Antioxidants/therapeutic use , Cytokines/metabolism , Dendrimers/pharmacology , Disease Models, Animal , Lung/pathology , Mice , NF-kappa B/metabolism , Phosphorus , Reactive Oxygen Species/metabolism
20.
Macromol Rapid Commun ; 43(8): e2100914, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35239224

ABSTRACT

The rational design of perfluorinated amphiphiles to control the supramolecular aggregation in an aqueous medium is still a key challenge for the engineering of supramolecular architectures. Here, the synthesis and physical properties of six novel non-ionic amphiphiles are presented. The effect of mixed alkylated and perfluorinated segments in a single amphiphile is also studied and compared with only alkylated and perfluorinated units. To explore their morphological behavior in an aqueous medium, dynamic light scattering (DLS) and cryogenic transmission electron microscopy/electron microscopy (cryo-TEM/EM) measurements are used. The assembly mechanisms with theoretical investigations are further confirmed, using the Martini model to perform large-scale coarse-grained molecular dynamics simulations. These novel synthesized amphiphiles offer a greater and more systematic understanding of how perfluorinated systems assemble in an aqueous medium and suggest new directions for rational designing of new amphiphilic systems and interpreting their assembly process.


Subject(s)
Molecular Dynamics Simulation , Microscopy, Electron, Transmission
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