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The light-harvesting excitonic properties of poly(phenylene ethynylene) (PPE) extended dendrimers (tree-like π-conjugated macromolecules) involve a directional cascade of local excitation energy transfer (EET) processes occurring from the "leaves" (shortest branches) to the "trunk" (longest branch), which can be viewed from a vibronic perspective as a sequence of internal conversions occurring among a connected graph of nonadiabatically coupled locally excited electronic states via conical intersections. The smallest PPE building block that is able to exhibit EET, the asymmetrically meta-substituted PPE oligomer with one acetylenic bond on one side and two parallel ones on the other side (hence, 2-ring and 3-ring para-substituted pseudo-fragments), is a prototype and the focus of the present work. From linear-response time-dependent density functional theory electronic-structure calculations of the molecule as regards its first two nonadiabatically coupled, optically active, singlet excited states, we built a (1 + 2)-state-8-dimensional vibronic-coupling Hamiltonian model for running subsequent multiconfiguration time-dependent Hartree wavepacket relaxations and propagations, yielding both steady-state absorption and emission spectra as well as real-time dynamics. The EET process from the shortest branch to the longest one occurs quite efficiently (about 80% quantum yield) within the first 25 fs after light excitation and is mediated vibrationally through acetylenic and quinoidal bond-stretching modes together with a particular role given to the central-ring anti-quinoidal rock-bending mode. Electronic and vibrational energy relaxations, together with redistributions of quantum populations and coherences, are interpreted herein through the lens of a nonadiabatic perspective, showing some interesting segregation among the foremost photoactive degrees of freedom as regards spectroscopy and reactivity. [ABSTRACT FROM AUTHOR]

BACKGROUND: In Alzheimers 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 (Aβ) 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.

Effective "soft" interactions between macromolecules such as polymers, amphiphilic dendrimers, and suitably designed DNA based dendritic molecules have been shown to be purely repulsive and non-diverging. We report the structure and phase behavior of a mixture of hard colloids and soft coarse-grained macromolecules. Through the use of Reference Interaction Site Model theory and molecular dynamics simulations we find that hard colloids and soft macromolecules act as depletants toward each other, generating a medium-induced effective attraction. This effective attraction leads to the formation of non-dispersed phases at high densities. At low and high fractions of hard colloids the system macrophase separates into two disparate regions of hard colloids and soft macromolecules. However, this system microphase separates into a hard-rich and soft-rich self-assembled domains at intermediate compositions. The formation of microphase separated structure in this system of isotropic, disconnected, and purely repulsive colloids is surprising and quite novel. This behavior is likely due to a softening of the interface between hard-rich and soft-rich self-assembled domains. Molecular dynamics simulations have revealed that the microphase separated state has an overall disordered bicontinuous morphology. The hard-rich domain forms an ordered FCC structure and the soft-rich domain forms a disordered cluster-fluid, making the structure simultaneously ordered and disordered. [ABSTRACT FROM AUTHOR]

Cancer cells engage in active aerobic glycolysis to meet their bioenergetic synthesis needs, which is known as the Warburg effect. Such a process leads to lactate accumulation in the tumor microenvironment (TME), further promoting cancer progression and inducing immunosuppression. Herein, functionalized dendrimer‐Cu(II) complexes (for short, D‐Cu(II)) as a nanocarrier, which enables a Fenton‐like reaction is developed to generate a large amount of hydroxyl radicals and shows a T1‐weighted magnetic resonance (MR) imaging performance. Importantly, the D‐Cu(II) allows efficient delivery of lactate oxidase (LOx) to cancer cells, directly downregulating the lactate levels. When combining with an immune activator of leukadherin‐1, the developed D‐Cu(II)/LOx complexes alleviate the symptoms of mouse leukemia. With a further coating of macrophage membranes, the generated D‐Cu(II)/LOx@M allows for effective blood‐brain barrier crossing to treat an orthotopic murine glioma model under the guidance of Cu(II)‐facilitated MR imaging. By integrating the LOx‐mediated lactate depletion with Cu(II)‐mediated chemodynamic therapy, the developed dendrimer nanomedicines improve the overall survival and antitumor immune responses of mice, and help to remodel the immunosuppressive TME in both cancer models, greatly sensitizing the treatment efficacy of immune activator. Such dendrimer technology may further be used for theranostics of other cancer types through lactate depletion‐enhanced combinational therapy. [ABSTRACT FROM AUTHOR]

The interactions of dendrimers having a phosphorus atom at each branching point, of type poly(phosphorhydrazone) (PPH), with different types of materials based on silicon and aluminum are reviewed. These dendrimers can be used for the functionalization of solid surfaces at the nanoscale, either by covalent immobilization, or by electrostatic interactions, especially for constructing perfectly controlled multi‐layers by layer‐by‐layer (LbL) deposit. The properties of such hybrid materials as chemical sensors, as very sensitive biological sensors, as well as substrates for the growing of cells are described. The PPH dendrimers can also be embedded inside materials. The resulting hybrid materials have been used for the capture of pollutants, in particular CO2 in air and chromate and methylene blue in waste water. [ABSTRACT FROM AUTHOR]

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 generate a dimerized TADF dendrimer, D4CzBNPh‐SF. Compared to its counterpart with a 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, when 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. [ABSTRACT FROM AUTHOR]

Mimicking nature, the reversible isomerization of hydrophobic dyes in aqueous solutions is appealing for bio-applications. Here, we report on the reversible isomerization of first-generation solvatochromic donor-acceptor Stenhouse adducts (DASAs) in water within dendritic matrices, realized either through the dendronization of DASAs or the incorporation of DASA pendants into dendronized copolymers. These dendritic macromolecules contain three-fold dendritic oligoethylene glycols (OEGs), which afford the macromolecules water-solubility and unprecedented thermoresponsive behavior. The thermoresponsive behavior of both dendronized DASAs and dendronized copolymers is dominated by the peripherals of dendritic OEGs. However, the hydrophilicity of the acceptor from DASA moieties also play a role in mediating their thermal phase transitions, and more importantly, tailor the hydrophobic interactions between dendritic OEGs and DASA moieties. Intriguingly, dendritic topologies contribute confinement to encapsulate the DASA moieties through crowding effects, and cooperative interactions from the crowded dendritic OEGs modulate the DASA moieties with different isomerization in aqueous media. The thermally induced collapse of dendritic OEGs, accompanied by the aggregation of dendritic macromolecules, leads to the formation of hydrophobic domains, which exert enhanced crowding effects to efficiently encapsulate the DASA moieties. Compared to the low molar mass of dendronized DASAs, thermally collapsed dendronized copolymers can efficiently retard the hydration of DASA pendants through cooperation between neighboring dendritic OEGs and afford the DASA pendants with better confined microenvironments to mediate their isomerization recovery by up to 90% from a cyclic charged (hydrophilic) state into a noncharged (hydrophobic) linear state in water. This dendritic confinement exhibits excellent fatigue resistance after several cycles of alternating photo-irradiation and thermal annealing at elevated temperatures. [ABSTRACT FROM AUTHOR]

In recent years, ion-imprinted polymers have gained significant attention and are extensively utilized owing to their high selectivity toward target ions. For this research, Pb(II) ions were used as the template ions, polyamide-amine dendrimers as the curing agent, epoxy resin as the carrier and combined with ion-imprinting technique in the preparation of Pb(II)-imprinted polymer (Pb(II)-IIP). Systematic adsorption experiments were used to investigate the impact of the adsorbent on the adsorption performance of Pb(II) ions. The composition of the adsorbent was further studied by FT-IR, SEM and other characterization techniques. The maximal adsorption capacity at pH = 5 and T = 318 K was calculated to be 138.8 mg/g. In the coexistence of multiple ions, the Pb(II)-IIP showed high selectivity for Pb(II) adsorption. Pb(II) was still removed at a rate of more than 91% after five cycles of experiments, indicating good reusability. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is a neuroimmunological disorder which causes axonal damage, demyelination and paralysis. Although numerous therapeutics have been developed for the effective treatment of MS and a few have been approved in recent decades, complete remission and treatment of MS remain a matter of concern. Nanotechnology is a potential approach for manipulating the properties of materials at the molecular level to attain desired properties. This approach is effective in the treatment of several CNS disorders by enhancing drug delivery, bioavailability and efficacy. We have briefly discussed the neuroimmunological disorders with a particular emphasis on MS. We also explored nanoengineered drug delivery systems, describing several nano-formulations for the treatment of MS, challenges and future of nanotechnology. [ABSTRACT FROM AUTHOR]

Surface plasmon resonance (SPR)-based biosensors have gained increasing prominence due to their ability to provide fast, accurate and real-time results. The functionalization of the SPR sensor chip is essential to ensure the effective binding of recognition biomolecules, making it a crucial step in the efficient construction of biosensors. We demonstrate here the functionalization of the SPR sensor chip with inorganic–organic nanocomposites formed by poly(amidoamine) dendrimers and silver nanoparticles (AgDENs). Several techniques were employed to characterize the structure and morphology of the nanocomposites. Silver nanoparticle/dendrimer structures with a size distribution between 3.7 and 16.2 nm were obtained, and chemical interactions were found between the amide groups of the dendrimers and the silver nanoparticles. Afterward, the synthesized AgDENs were combined with cysteamine using the layer-by-layer (LbL) technique to create multivalent films on the SPR sensor chip. To assess the versatility of these molecular assemblies in the biomaterial anchoring process, studies involving the immobilization of different types of proteins, including the Chaperone CHIP protein (carboxyl terminus of the Hsc70-interacting protein), heat shock cognate protein 70 (Hsc70), Free Candida antarctica lipase B (CALB L), and a recombinant protein (C1 protein) from the protozoan Leishmania infantum to the AgDENs were conducted. To evaluate a specific application, an immunosensor was constructed by anchoring the C1 protein on the proposed platform (AgDENs) to selectively detect Leishmania infantum antibodies in canine serum samples from positive and negative groups for visceral leishmaniasis. In brief, the nanostructured materials composed of poly(amidoamine) dendrimers and silver nanoparticles proved to be effective in anchoring different biological recognition elements, demonstrating their versatility for biosensor applications. An increase in sensor interface sensitivity was observed, likely due to the coupling of localized surface plasmons of silver nanoparticles with the plasmon of the flat Au. The large surface area of the film, combined with its excellent chemical stability, shows that the proposed platform is a very interesting strategy in biosensing. [ABSTRACT FROM AUTHOR]

Dendrimers are polymeric compounds which exhibit notable advantages, particularly in medicinal chemistry. The therapeutic potential of these molecular architectures can be screened through in silico method which facilitates the identification of the ones with the highest potential for further investigation. Here, we have reported the in silico investigation of a series of dendritic architecture based on para‐substituted aniline. Density functional theory (DFT) method was employed to optimize the structures and to analyze the quantum chemical parameters. The absorption, distribution, metabolism, excretion, and toxicity (ADMET) profiling was additionally assessed, which unveiled favorable drug‐like characteristics and moderate to good bioactivity across all compounds. Utilizing the drug‐likeness property in machine learning techniques, the potential for predicting novel drug‐like dendrimers was explored. [ABSTRACT FROM AUTHOR]

Different from conventional luminescent dendrimers with fluorophore tethered outside to dendron, here we first developed endo‐encapsulated luminescent dendrimers with multi‐resonance (MR) fluorophore embedded inside of carbazole dendrons by growing dendrons through 1,8‐positions of central carbazole moiety to create a cavity for accommodating the fluorophore. This endo‐encapsulated structure not only shields the fluorophore to fully resist aggregation‐caused spectral broadening, but also induce through‐space interactions between dendron and fluorophore via intramolecular π‐stacking, giving lowered singlet state energy and reduced singlet‐triplet energy splitting to accelerate reverse intersystem crossing (RISC) from triplet to singlet states. The resultant dendrimer containing 1,8‐linked second‐generation carbazole dendrons and boron, sulfur‐doped polycyclic MR fluorophore exhibits narrowband blue emission at 471 nm with FWHM kept at 34 nm even in neat film, together with ~4 times enhancement of RISC rate constant compared to its exo‐tethered counterpart. Solution‐processed OLEDs based on the endo‐encapsulated dendrimer reveal efficient narrowband blue emissions with maximum external quantum efficiency of 22.6 %, representing the best device efficiency for blue‐emitting multi‐resonance dendrimers so far. [ABSTRACT FROM AUTHOR]

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. Graphical Abstract [ABSTRACT FROM AUTHOR]

The focus of nanoparticles in vivo trafficking has been mostly on their tissue-level biodistribution and clearance. Recent progress in the nanomedicine field suggests that the targeting of nanoparticles to immune cells can be used to modulate the immune response and enhance therapeutic delivery to the diseased tissue. In the presence of tumor lesions, monocytic-myeloid-derived suppressor cells (M-MDSCs) expand significantly in the bone marrow, egress into peripheral blood, and traffic to the solid tumor, where they help maintain an immuno-suppressive tumor microenvironment. In this study, we investigated the interaction between PAMAM dendrimers and M-MDSCs in two murine models of glioblastoma, by examining the cell-level biodistribution kinetics of the systemically injected dendrimers. We found that M-MDSCs in the tumor and lymphoid organs can efficiently endocytose hydroxyl dendrimers. Interestingly, the trafficking of M-MDSCs from the bone marrow to the tumor contributed to the deposition of hydroxyl dendrimers in the tumor. M-MDSCs showed different capacities of endocytosing dendrimers of different functionalities in vivo. This differential uptake was mediated by the unique serum proteins associated with each dendrimer surface functionality. The results of this study set up the framework for developing dendrimer-based immunotherapy to target M-MDSCs for cancer treatment. [Display omitted] • Monocytic MDSC (M-MDSC) in the tumor show high capacity of taking up dendrimers. • The recruitment of M-MDSCs contribute to the dendrimer accumulation in the tumor. • Dendrimer surface chemistry affects their interactions with M-MDSCs. • Dendrimer protein corona mediates the interactions between dendrimers and M-MDSCs. [ABSTRACT FROM AUTHOR]

The present study synthesized a novel dendrimer with specific functional groups and use them as pharmaceutical carriers at the nanoscale. First, a glycodendrimer was synthesized and a porphyrin substance was selected as its core. Afterward, this substance was subsequently reacted with gallic acid and bromo valerate step-by-step and it was conjugated with acrylonitrile functionalized with Tris (hydroxymethyl) aminomethane. Eventually, the composition was reacted with Tris [α-D Manos (pyrazolyl oxy) methyl] methylamine and glycodendrimer (TTP-Tr-GD) was prepared via a divergent approach to develop drug delivery system. The nanocarrier was characterized using several techniques, such as scanning electron microscopy (FE-SEM), thermal analysis (TGA), NMR, Fourier transform infrared (FT-IR), differential laser scanning (DLS), elemental mapping (EDS), and Zeta potential. Effective factors on the release of the drug delivery, including the best time to absorb, sample pH, and reaction temperature were optimized. The statistically optimized sorption efficiency (98.11%) was attained at pH = 5.5, and a contact time of 15 min. As a result of the functional groups on the surface of the TTP-Tr-GD are appropriate for simultaneous determination and high throughput analysis of drug delivery system. [ABSTRACT FROM AUTHOR]

Dendrimers, distinguished by their mono-dispersed globular or spheroid macromolecular structures with repeated branches, exhibit unique and desirable characteristics that set them apart from other polymers. These characteristics include their nanoscopic size, precise control over molecular structure, low polydispersity index, water solubility, exceptional physicochemical stability, self-assembly capabilities, polyvalency, chemical stability, electrostatic interactions, solubility, and minimal cytotoxicity. Dendrimers are prepared from monomers using either divergent or convergent step-growth polymerization. Dendrimers have the ability to reduce the toxicity of medications while enhancing their effectiveness. This review will delve into various types of dendrimers such as poly (amidoamine) dendrimers, peptide dendrimers, smart dendrimers, polyethylene glycol dendrimers, poly (propylene imine) dendrimers, polyester dendrimers, Janus dendrimers, and etc. in the field of drug delivery and gene delivery systems that utilize them. Dendrimer-drug conjugates offer numerous benefits over conventional drug carriers, such as enhanced drug uptake by the tumor, reduced systemic toxicity issues, and increased antitumor activity of the administrated medications. To achieve this objective, the authors utilized the Science Direct, PubMed, and Scopus databases to acquire the information, evaluating references individually, extracting essential details, and assessing the quality of the included studies. [ABSTRACT FROM AUTHOR]

A composite comprising a silver nanoparticles‐loaded poly(amidoamine) (PAMAM) dendrimer crosslinked with glutaraldehyde (PAMAM/AgNPs) is synthesized using a one‐step method under vortex at room temperature. The structure of glutaraldehyde‐crosslinked PAMAM dendrimer is characterized using FTIR and high‐resolution magic angle spinning–carbon 13 nuclear magnetic resonance (HRMAS 13C NMR) spectroscopy. The crosslinking structure ensures the uniformity and stability of the Ag nanoparticles, and the flexibility of the PAMAM/AgNPs composite. X‐ray diffraction (XRD) analysis and energy dispersive spectroscopy (EDS) confirm the formation of Ag nanoparticles in the PAMAM/AgNPs composite. Scanning electron microscopy (SEM) and three‐dimensional (3D) micro‐Raman images reveal the coarsely porous 3D micro‐structure of the PAMAM/AgNPs composite. This unique micro‐3D architecture provides the PAMAM/AgNPs composite with spongy flexibility and a swab‐like nature, which is advantageous for the rapid and effective absorption of liquid samples on the surfaces of objects. Surface enhanced Raman spectroscopy (SERS) indicates that the detection limits of both rhodamine 6G (R6G) and thiram are 1.0 × 10−5 mol L−1, and the SERS enhancement factor of R6G is determined to be 1.35 × 104. The spongy flexible PAMAM/AgNPs SERS substrate therefore has potential for use in Raman active compound detection. [ABSTRACT FROM AUTHOR]

This study investigates the removal of Congo red dye from aqueous solution using functionalized generation 3.0 and 5.0 Polyamidoamine dendrimer – silica gel composite (G-3PS, G-5PS). Fourier Transform-Infra Red spectroscopy, Brunauer Emmett and Teller, Thermogravimetric Analysis, pH at point of zero charge, and Scanning Electron Microscopy measurements have been applied to characterize the synthetic nanohybride composite, these techniques revealed the successful functionalization of both dendrimer molecules and subsequent immobilization onto silica gel. The implications of varying adsorption parameters such as contact time, initial concentration of adsorbate, temperature and pH on both composites were studied. Experimental data obtained from batch adsorption processes were fitted into two equilibrium isotherms (Langmuir and Freundlich) and 3 kinetic models (Pseudo-First-Order, Pseudo-Second-Order, Intra Particle Diffusion). Adsorption mechanism was mainly governed by film diffusion due to electrostatic interactions between the functionalized dendrimer surface and Congo red molecules. Thermodynamic parameters illustrate that the adsorption is endothermic and spontaneous. Findings suggest the Nanocomposites G-3PS G-5PS) are good adsorbents for the removal of Congo red dye from aqueous solutions. [ABSTRACT FROM AUTHOR]

The rapid emergence and spread of multidrug-resistant bacterial pathogens require the development of antibacterial agents that are robustly effective while inducing no toxicity or resistance development. In this context, we designed and synthesized amphiphilic dendrimers as antibacterial candidates. We report the promising potent antibacterial activity shown by the amphiphilic dendrimer AD1b, composed of a long hydrophobic alkyl chain and a tertiary amine-terminated poly(amidoamine) dendron, against a panel of Gram-negative bacteria, including multidrug-resistant Escherichia coli and Acinetobacter baumannii. AD1b exhibited effective activity against drug-resistant bacterial infections in vivo. Mechanistic studies revealed that AD1b targeted the membrane phospholipids phosphatidylglycerol (PG) and cardiolipin (CL), leading to the disruption of the bacterial membrane and proton motive force, metabolic disturbance, leakage of cellular components, and, ultimately, cell death. Together, AD1b that specifically interacts with PG/CL in bacterial membranes supports the use of small amphiphilic dendrimers as a promising strategy to target drug-resistant bacterial pathogens and addresses the global antibiotic crisis. [ABSTRACT FROM AUTHOR]

Inspired by mussels protein adhesives, two series of catechol‐functionalized Linear‐Dendritic Block Copolymer (LDBC) adhesives are synthesized. They show lap shear adhesion strength as high as 7 MPa on aluminum substrates and adhesion up to 3 kPa on porcine skin. These water‐soluble LDBCs are composed of i) either poly(ethylene glycol) (PEG) or poly(ethylene glycol)‐poly(propylene glycol)‐poly(ethylene glycol) triblock copolymer (Pluronic F‐127) as linear polymers, ii) Bis‐MPA dendrons of generation 0, 1, and 2 as dendritic parts, and iii) 2, 4, or 8 terminal catechol moieties. A LDBCs generation comparative test on aluminum reveals a clear dendritic effect: the LDBCs of second generation display higher adhesion than the LDBCs of first generation that also display higher adhesion than the LDBCs of generation 0 for both series, assessing thus a positive dendritic effect in adhesion. Second, a comparative study is carried out between the LDBCs based on PEG and the ones based on Pluronic. The ability of the Pluronic LDBCs to self‐assemble in water appears to reduce adhesion when applied on aluminum whereas it is essential to obtain adhesion on porcine skin, thanks to the formation of hydrogels, as observed by the vial inversion technique and electron microscopy. [ABSTRACT FROM AUTHOR]

Various heterogeneous bimetallic Ru, Rh, Pd and/or Cu‐containing catalysts, based on dendrimer‐silica mesoporous hybrid supports, are successfully synthesized, using co‐complexation method, and characterized by transmission electron microscopy and X‐ray photoelectron spectroscopy. The catalysts obtained are examined in the aqueous hydrogenation of levulinic acid and its esters to γ‐valerolactone. The catalyst activity and selectivity on γ‐valerolactone are strongly dependent on the nature and ratio of metal used, and PdRu bimetallic catalysts are found to be the most effective. Quantitative or near to quantitative yields of γ‐valerolactone can be achieved for all PdRu catalysts and substrates tested within 2 hours, with maximum TOF value of 4500 h−1. Such high efficiency is provided by especial nanoparticle structure, consisted of Pd core and RuPd shell, and synergistic effect between Ru and Pd in alloy. [ABSTRACT FROM AUTHOR]

PEGylated PAMAM dendrimers (PEG‐PAMAM) are well‐characterized biomaterials with still unexplored applications as carriers of drugs acting via membrane receptors, such as octreotide. This work confirmed the safety and negligible internalization capacity of fourth‐generation 50%‐PEG‐PAMAM in HEK‐293 cells, to then assessed their supramolecular binding to octreotide through tryptophan quenching experiments and Gaussian‐accelerated molecular dynamics (GaMD) simulations. Tryptophan quenching showed that PEG‐PAMAM binds octreotide with a Kbind of 6 × 106 M−1 and a complex stoichiometry of 1:1.4, unlike native PAMAM. GaMD simulations revealed that octreotide binds at the outer PEG shell of PEG‐PAMAM, potentially hindering the drug from proteolytic degradation and enabling its release at a membrane level. Viability experiments on HeLa, PC‐12, and HEK‐293 cells incubated with increasing concentrations of octreotide in free drug solutions and equimolar mixtures with PEG‐PAMAM confirmed that the PEGylated dendrimer acts as an efficient supramolecular carrier for octreotide and enhances the antiproliferative effects of the drug. Our findings highlight a novel facet for PEG‐PAMAM dendrimers as macromolecular vehicles for peptide or non‐peptide drugs acting via membrane receptor sites. [ABSTRACT FROM AUTHOR]

The importance of avian influenza virus (AIV) detection in clinical diagnosis and prognosis has been deeply recognized. In this study, the ultrasensitive detection of AIV subtype H5N1 was achieved by ICP-MS combined with DNA dendrimer-carried silver nanoparticle (AgNP) labeling. First, a magnetic control system was constructed by anchoring double-strand DNAs (dsDNAs) which contained a complementary sequence of H5N1 and two locked triggers on the surface of magnetic beads (MBs). When H5N1 was present, the two triggers were released and initiated dendrimer hybridization chain reactions which led to the generation of DNA dendrimer-carried AgNPs on the surface of the MBs. Finally, the AgNPs were collected via magnetic separation, digested by nitric acid, and tested using ICP-MS. The signal intensities of 107Ag were positively correlated with the concentrations of H5N1. Notably, the DNA dendrimer assembly contributed to significant signal amplification and good sensitivity with the limit of detection as low as 2.0 × 10−11 mol L−1. Moreover, the method displayed favorable selectivity against mismatched H5N1 and good recoveries in human serum samples. It is a promising analytical tool for the H5N1 virus and other subtypes of AIV, and has potential value in clinical diagnosis and prognosis of infectious diseases. [ABSTRACT FROM AUTHOR]

In response to the health and environmental concerns associated with the plasticizer dioctyl phthalate (DOP), this research explores the utilization of methyl oleate (MO) derived from plant oil, 1,2,4‐Benzeneticarboxylic anhydride (TMA) and isobutyric anhydride (IA) as a precursor for synthesizing a hyperbranched polyester named IA‐MO‐TMA. This polyester serves as an alternative plasticizer for Polyvinyl chloride (PVC). The chemical structure of IA‐MO‐TMA was thoroughly characterized using Fourier Transform Infrared Spectrometer (FTIR) and nuclear magnetic resonance hydrogen spectra, and its molecular weight was assessed. The PVC film, plasticized with IA‐MO‐TMA, underwent comprehensive testing using techniques such as differential scanning calorimetry, scanning electron microscopy, and thermogravimetric analysis. Notably, the glass transition temperature (Tg) of the plasticized PVC film exhibited a significant reduction from 75°C to −6.7°C. The plasticized film demonstrated an elongation at break of 318.1%, a tensile strength of 19.2 MPa, and a plasticizing efficiency of 109.9%. Moreover, the use of IA‐MO‐TMA as a plasticizer increased the initial decomposition temperature of PVC film from 235.6 to 264.1°C. Additionally, the extraction rate of IA‐MO‐TMA in petroleum ether was found to be 35.6% lower than that of DOP. [ABSTRACT FROM AUTHOR]

A polyyne dendrimer (PD) was synthesized in four-steps and characterized by 1H NMR, 13C NMR, MS, FT-IR, etc. Subsequently, ultraviolet visible (UV-Vis) absorption spectra and fluorescence spectra were further investigated in a series of solvents, in which obvious aggregation-induced emission (AIE) were observed. In addition, the electrochemiluminescence (ECL)properties in solid state were also investigated. Interestingly, the π-extended PD with slight distorted configuration possessed intense and stable cathodic ECL emission, which indicatedthat it has potential application in the future construction of high-performance ECL emitters. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Core–shell tecto dendrimers (CSTDs) with excellent physicochemical properties and good tumor penetration and gene transfection efficiency have been demonstrated to have the potential to replace high‐generation dendrimers in biomedical applications. However, their characterization and related biological properties of CSTDs for enhanced tumor penetration and gene delivery still lack in‐depth investigation. Herein, three types of dual‐responsive CSTDs are designed for thorough physicochemical characterization and investigation of their tumor penetration and gene delivery efficiency. Three types of CSTDs are prepared through phenylborate ester bonds of phenylboronic acid (PBA)‐decorated generation 5 (G5) poly(amidoamine) (PAMAM) dendrimers as cores and monose (galactose, glucose, or mannose)‐conjugated G3 PAMAM dendrimers as shells and thoroughly characterized via NMR and other techniques. It is shown that the produced CSTDs display strong correlation signals between the PBA and monose protons, similar hydrodynamic diameters, and dual reactive oxygen species‐ and pH‐responsivenesses. The dual‐responsive CSTDs are proven to have structure‐dependent tumor penetration property and gene delivery efficiency in terms of small interference RNA for gene silencing and plasmid DNA for gene editing, thus revealing a great potential for different biomedical applications. [ABSTRACT FROM AUTHOR]

This review article explores the recent innovations in the field of antimicrobial and antiviral macromolecules. With the rising challenge of antibiotic resistance, as well as the overuse of antibiotics, there is a growing demand for efficient solutions to combat microbial and viral infections. The development of new effective antimicrobial and antiviral agents is highlighted. This review is designed to give a comprehensive view of the literature focusing on a few examples of combating microbial and viral infections in each section. A brief description of naturally occurring organic‐based materials that exhibit antimicrobial and/or antiviral activities is presented, focusing on polysaccharides, peptides, and proteins. Synthetic organic‐based materials are divided into subsections including polymers, dendrimers, and nanomaterials. The synthesis and applications of inorganic materials such as polyphosphazenes and polysiloxanes, as well as tin‐, germanium‐ and gallium‐based materials are emphasized in this review. Organometallic macromolecules are also described, and their antimicrobial and antiviral activities are examined. Overall, this article provides a comprehensive overview of recent advancements in the design of antimicrobial and antiviral macromolecules, offering valuable insights into their potential applications in biomedical research and combating drug‐resistant microorganisms and viruses. [ABSTRACT FROM AUTHOR]

Recently, much research has focused on the search for new mixed donor–acceptor layers for applications in organic electronics. Organic heterostructures with layers based on the generation 1 poly(propylene thiophenoimine) (G1PPT) dendrimer, N,N′-diisopropylnaphthalene diimide (MNDI), and a combination of the two were prepared and their electrical properties were investigated. Single layers of G1PPT and MNDI and a mixed layer (G1PPT:MNDI) were obtained via spin coating on quartz glass, silicon, and glass/ITO substrates, using chloroform as a solvent. The absorption mechanism was investigated, the degree of disorder was estimated, and the emission properties of the layers were highlighted using spectroscopic methods (UV–Vis transmission and photoluminescence). The effects of the concentration and surface topographical particularities on the properties of the layers were analyzed via atomic force microscopy. All of the heterostructures realized with ITO and Au electrodes showed good conduction, with currents of the order of mA. Additionally, the heterostructure with a mixed layer exhibited asymmetry in the current–voltage curve between forward and reverse polarization in the lower range of the applied voltages, which was more significant at increased concentrations and could be correlated with rectifier diode behavior. Consequently, the mixed-layer generation 1 poly(propylene thiophenoimine) dendrimer with N,N′-diisopropylnaphthalene diimide can be considered promising for electronic applications. [ABSTRACT FROM AUTHOR]

Tropomyosin kinase receptor B (TrkB) has been explored as a therapeutic target for neurological and psychiatric disorders. However, the development of TrkB agonists was hindered by our poor understanding of the TrkB agonist binding location and affinity (both affect the regulation of disorder types). This motivated us to develop a combined computational and experimental approach to study TrkB binders. First, we developed a docking method to simulate the binding affinity of TrkB and binders identified by our magnetic drug screening platform from Gotu kola extracts. The Fred Docking scores from the docking computation showed strong agreement with the experimental results. Subsequently, using this screening platform, we identified a list of compounds from the NIH clinical collection library and applied the same docking studies. From the Fred Docking scores, we selected two compounds for TrkB activation tests. Interestingly, the ability of the compounds to increase dendritic arborization in hippocampal neurons matched well with the computational results. Finally, we performed a detailed binding analysis of the top candidates and compared them with the best-characterized TrkB agonist, 7,8-dyhydroxyflavon. The screening platform directly identifies TrkB binders, and the computational approach allows for the quick selection of top candidates with potential biological activities based on the docking scores. [ABSTRACT FROM AUTHOR]

[Display omitted] By combination of dendritic topological structures with photopolymerizable diacetylene, here we report on supramolecular chiral assembly of the dendronized diacetylenes in water. These dendronized diacetylenes are constituted with three-fold dendritic oligoethylene glycols (OEGs), bridged with a dipeptide from phenylalanine and glycine. These dendronized amphiphiles exhibit intensive propensity to aggregate in water and form helical fibers, which show characteristic thermoresponsive behavior with phase transition temperatures dominated by hydrophilicity of the dendritic OEGs. Topochemical polymerization of these supramolecular fibers through UV irradiation transfers them into the covalent helical dendronized polydiacetylenes. Chirality of these dendronized polydiacetylenes can be mediated through the thermally-induced phase transitions, but is also intriguingly dependent on vortex via stirring. Through stirring the solutions, chiralities of the dendronized polydiacetylenes are inverted, which can be reversibly recovered after keeping still the solution. Hydrogels are formed from these dendronized diacetylenes through concentration-enhanced interactions between the supramolecular fibers. Their mechanical properties can be greatly increased through thermally-enhanced interactions between the fibers with storage moduli increased from 20 Pa to a few hundred Pa. In addition, through photo-polymerization, the supramolecular fibers are transferred into covalent dendronized polydiacetylenes, and the corresponding hydrogels show much improved mechanical properties with storage moduli about 10 kPa. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Abstract Multiple sclerosis (MS) is a neuroimmunological disorder which causes axonal damage, demyelination and paralysis. Although numerous therapeutics have been developed for the effective treatment of MS and a few have been approved in recent decades, complete remission and treatment of MS remain a matter of concern. Nanotechnology is a potential approach for manipulating the properties of materials at the molecular level to attain desired properties. This approach is effective in the treatment of several CNS disorders by enhancing drug delivery, bioavailability and efficacy. We have briefly discussed the neuroimmunological disorders with a particular emphasis on MS. We also explored nanoengineered drug delivery systems, describing several nano-formulations for the treatment of MS, challenges and future of nanotechnology.

The scattering functions of nine generations of ideal tri-functional comb and dendrimer polymers are computed by novel graph techniques. The properties of polymers having from 9 to 3069 branches are explored. The g-ratios and the scattering functions indicate that as the number of branches increases, comb polymers behave more and more like linear polymers with half the number of branches, whereas dendrimers become more like spherical objects. [ABSTRACT FROM AUTHOR]

Polyoxyalkylenes are widely studied as clay swelling inhibitors. Although many additives are available, the operations require more efficient formulations. This work synthesized and characterized two of molecules: poly(ethylene glycol)(PEG) modified with hydrocarbon chains of different lengths; and poly(amidoamine) dendrimers(PAMAM) and PEG-modified PAMAM. The clay swelling inhibition efficiency was evaluated by the Foster swelling test. For the hydrophobized PEG derivatives, there is an optimum hydrocarbon chain size (C6-C10) to achieve the best performance. The best result was obtained for PEG-modified PAMAM(1:1), tested for the first time, being its performance even better than a commercial additive widely used in the petroleum industry. [ABSTRACT FROM AUTHOR]

Cr (III) is an essential element for maintaining glucose, lipid, and protein metabolism in mammals. Removal/recovery of such heavy metals is crucial. For this purpose, dendrimer-based novel magnetic nanoparticles to enrich Cr (III) were synthesized and characterized by spectroscopic methods such as SEM-EDX, TEM, FT-IR, XRD, and VSM. The optimum parameters such as pH, eluent type-concentration, adsorbent amount, and time, which are important in the recovery of Cr (III) with solid magnetic-based nanoparticles (MNPs), were determined by flame atomic absorption spectroscopy. After the enrichment of Cr (III) with MNPs, the device's detection power enhancements were increased by 8653 ± 145 times. The optimum conditions obtained for Cr (III) ions with MNPs were successfully applied to water, honey, and hardaliye samples. Furthermore, the reusability results of the MNPs were determined to be approximately 99% for Cr (III) up to the 10th use. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

One of the intensively developed tools for cancer therapy is drug-releasing matrices. Polyamidoamine dendrimers (PAMAM) are commonly used as nanoparticles to increase the solubility, stability and retention of drugs in the human body. Most often, drugs are encapsulated in PAMAM cavities or covalently attached to their surface. However, there are no data on the use of PAMAM dendrimers as a component of porous matrices based on polyurethane foams for the controlled release of drugs and biologically active substances. Therefore, in this work, porous materials based on polyurethane foam with incorporated third-generation poly(amidoamine) dendrimers (PAMAM G3) were synthesized and characterized. Density, water uptake and morphology of foams were examined with SEM and XPS. The PAMAM was liquefied with polyether polyol (G441) and reacted with polymeric 4,4′-diphenylmethane diisocyanate (pMDI) in the presence of silicone, water and a catalyst to obtain foam (PF1). In selected compositions, the castor oil was added (PF2). Analogs without PAMAM G3 were also synthesized (F1 and F2, respectively). An SEM analysis of foams showed that they are composed of thin ribs/walls forming an interconnected network containing hollow bubbles/pores and showing some irregularities in the structure. Foam from a G3:G441:CO (PF2) composition is characterized by a more regular structure than the foam from the composition without castor oil. The encapsulation efficiency of drugs determined by the XPS method shows that it varies depending on the matrix and the drug and ranges from several to a dozen mass percent. In vitro biological studies with direct contact and extract assays indicated that the F2 matrix was highly biocompatible. Significant toxicity of dendrimeric matrices PF1 and PF2 containing 50% of PAMAM G3 was higher against human squamous carcinoma cells than human immortalized keratinocytes. The ability of the matrices to immobilize drugs was demonstrated in the example of perspective (Nimesulide, 8-Methoxypsolarene) or approved anticancer drugs (Doxorubicin—DOX, 5-Aminolevulinic acid). Release into the culture medium and penetration of DOX into the tested SCC-15 and HaCaT cells were also proved. The results show that further modification of the obtained matrices may lead to their use as drug delivery systems, e.g., for anticancer therapy. [ABSTRACT FROM AUTHOR]

Tris‐bidentate iridium(III) complexes used in organic light‐emitting diodes (OLEDs) are typically homoleptic or heteroleptic with three or two identical emissive ligands, respectively. Herein red phosphorescence emitting dendrimers composed of first generation biphenyl dendrons, 2‐ethylhexyloxy surface groups and an iridium(III) complex core with three, two or one emissive [4‐phenyl]−2‐[thiophen‐2‐yl]quinoline ligands are reported. The dendrimers have similar photoluminescence quantum yields (PLQYs) in solution (84–88%), neat film (23–25%) and when blended with tris(4‐carbazoyl‐9‐ylphenyl)amine (72–73%), enabling the effect of the number of emissive ligands on OLED performance to be determined. The external quantum efficiency (EQE) of OLEDs composed of neat dendrimer films increased with decreasing number of emissive ligands, with the device composed of the dendrimer having a single emissive ligand having an EQE of 9.2%, which is almost double that expected from a bottom emitting device and a film PLQY of 25 ± 3.6%. The emission is Lambertian and the higher‐than‐expected EQE is ascribed to alignment of the single emissive ligand being optimal for light‐outcoupling. The EQE of OLEDs containing the blend film also increased with decreasing emissive number of ligands (maximum EQE = 15.4%). [ABSTRACT FROM AUTHOR]

Isocyanate‐based monomers and polymers have found widespread industrial application; however, the realization of green water‐based products via the preparation of stable isocyanate aqueous emulsions remains challenging. Herein, a series of organosilicon and organofluorine synergistically modified amphiphilic branched polyurethanes (HBWPU), synthesized by grafting perfluorohexyl ethanol semi‐terminated isophorone diisocyanate (IPDI) onto a hydrophilic polyurethane prepolymer, is presented. Subsequently, using a physical mixing method, stable diisocyanate emulsions are fabricated by preparing diisocyanate latex particles with IPDI as the core and hyperbranched water‐based polyurethanes (HBWPU) as the shell. Structural investigations showed that the branching degree and fluorine content of the HBWPU significantly affects the stability of the diisocyanate emulsions. Increasing the degree of branching from 0.34 to 0.86 causes the amount of residual isocyanate (NCO) groups to decrease from 20.1% to 16.7%. In contrast, an increase in the fluorine content from 0% to 17.8% increases the amount of residual NCO groups from 11.5% to 24.6%. Thus, HBWPU can be used as an emulsifier to prepare waterborne diisocyanate cross‐linking agents. Such polyurethane‐coated isocyanate aqueous emulsions can increase the hardness and significantly improve the acetone resistance of hydroxyl polyacrylate resins. [ABSTRACT FROM AUTHOR]

Polymyxin B (PMB) is often considered as the last line of defense for treating carbapenem‐resistant Klebsiella pneumoniae (CRKP). However, its efficacy is hindered by limited penetration across the blood‐air barrier in the lung due to its low lipid solubility. To simultaneously increase PMB in epithelial lining fluid while suppressing the excessive inflammatory response in the lung, a novel nano‐biomimetic system "Siv‐PMB@G4@MM" is designed and fabricated by encapsulating PMB‐ and anti‐inflammatory Sivelestat (Siv)‐loaded G4 PAMAM dendrimers with macrophage membranes (MM). The Siv‐PMB@G4@MM displayed a superior acidic pH‐responsive release property and can target inflamed lung tissues, greatly increasing the concentrations of PMB and Siv at the infection site. Compared with free drugs, Siv‐PMB@G4@MM demonstrated superior synergistic antibacterial and anti‐inflammatory activities. Moreover, due to the ability of MM to sequester lipopolysaccharide (LPS) and some pro‐inflammatory cytokines, Siv‐PMB@G4@MM further enhanced the anti‐inflammatory potential of Siv. In mouse models of LPS‐induced acute lung injury, pulmonary bacterial infection, and sepsis‐induced pneumonia, Siv‐PMB@G4@MM significantly reduced inflammatory responses and/or bacterial burdens, mitigated neutrophil infiltration and pulmonary edema, and decreased neutrophil extracellular trap (NET) secretion. The highly improved biocompatibility and efficiency of the multifunctional Siv‐PMB@G4@MM presents a promising strategy for the clinical treatment of antibiotic‐resistant bacterial pneumonia. [ABSTRACT FROM AUTHOR]

A folic acid-targeted polyurea (PURE) dendrimer was easily radiolabelled with Technetium-99m (99mTc-PUREG4-FA2) avoiding the use of additional ligands and bioconjugation chemistry. This straightforward strategy is enabled in PURE dendrimers due to their favourable surface terminal groups configuration, showing coordination capabilities and turning these biodendrimers into attractive platforms for nanoradiotheranostics. [ABSTRACT FROM AUTHOR]

The review considers several aspects of the synthesis of dendrimers related to the efficient achievement of their mass and high functionality. These are synthetic methods based on a block scheme for the production of dendrimers and click reactions in the processes of dendritic growth. A method for the synthesis of dendrimers, in which their rapid growth and size are achieved through the use of long spacers between branch points, is also considered. In general, all of these approaches are aimed at the formation of highly functional or high molecular weight molecules with a dendrimer structure in a short time. [ABSTRACT FROM AUTHOR]

Carbon‐chain dendritic polymers hold unique properties and promising applications. However, synthesizing carbon‐chain dendrimers, beyond conjugated ones, remains a challenge. Here, the use of the iterative single unit monomer insertion technique for synthesizing 2.5 generation partial‐carbon‐chain dendrimers (G2.5) is described, utilizing bismaleimide as the core, a maleimide–trithiocarbonate conjugate as the branching unit, and indene as the spacer unit, following a divergent growth strategy. The optimized conditions for synthesizing the maleimide–trithiocarbonate branching unit are a bismaleimide to trithiocarbonate ratio of 5:1 and a reaction time of 30 min. The structures are verified using 1H nuclear magnetic resonance, gel permeation chromatography, and matrix‐assisted laser desorption/ionization‐time of flight mass spectra. A four‐arm star polymer is then synthesized using the G2.5 as the core. This synthesis of a partial‐carbon‐chain dendrimer establishes a foundational step toward creating all‐carbon‐chain ones and may open new application avenues in material science. [ABSTRACT FROM AUTHOR]

Nanotechnology has ushered in significant advancements in drug design, revolutionizing the prevention, diagnosis, and treatment of various diseases. The strategic utilization of nanotechnology to enhance drug loading, delivery, and release has garnered increasing attention, leveraging the enhanced physical and chemical properties offered by these systems. Polyamidoamine (PAMAM) dendrimers have been pivotal in drug delivery, yet there is room for further enhancement. In this study, we conjugated PAMAM dendrimers with chitosan (CS) to augment cellular internalization in tumor cells. Specifically, doxorubicin (DOX) was initially loaded into PAMAM dendrimers to form DOX-loaded PAMAM (DOX@PAMAM) complexes via intermolecular forces. Subsequently, CS was linked onto the DOX-loaded PAMAM dendrimers to yield CS-conjugated PAMAM loaded with DOX (DOX@CS@PAMAM) through glutaraldehyde crosslinking via the Schiff base reaction. The resultant DOX@CS@PAMAM complexes were comprehensively characterized using Fourier-transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), and dynamic light scattering (DLS). Notably, while the drug release profile of DOX@CS@PAMAM in acidic environments was inferior to that of DOX@PAMAM, DOX@CS@PAMAM demonstrated effective acid-responsive drug release, with a cumulative release of 70% within 25 h attributed to the imine linkage. Most importantly, DOX@CS@PAMAM exhibited significant selective cellular internalization rates and antitumor efficacy compared to DOX@PAMAM, as validated through cell viability assays, fluorescence imaging, and flow cytometry analysis. In summary, DOX@CS@PAMAM demonstrated superior antitumor effects compared to unconjugated PAMAM dendrimers, thereby broadening the scope of dendrimer-based nanomedicines with enhanced therapeutic efficacy and promising applications in cancer therapy. [ABSTRACT FROM AUTHOR]

In the pursuit of achieving better therapeutic outcomes in the treatment of HIV, innovative drug delivery strategies have been extensively explored. Mannose receptors, which are primarily found on macrophages and dendritic cells, offer promising targets for drug delivery due to their involvement in HIV pathogenesis. This review article comprehensively evaluates recent drug delivery system advancements targeting the mannose receptor. We have systematically described recent developments in creating and utilizing drug delivery platforms, including nanoparticles, liposomes, micelles, noisomes, dendrimers, and other nanocarrier systems targeted at the mannose receptor. These strategies aim to enhance drug delivery specificity, bioavailability, and therapeutic efficacy while decreasing off-target effects and systemic toxicity. Furthermore, the article delves into how mannose receptors and HIV interact, highlighting the potential for exploiting this interaction to enhance drug delivery to infected cells. The review covers essential topics, such as the rational design of nanocarriers for mannose receptor recognition, the impact of physicochemical properties on drug delivery performance, and how targeted delivery affects the pharmacokinetics and pharmacodynamics of anti-HIV agents. The challenges of these novel strategies, including immunogenicity, stability, and scalability, and future research directions in this rapidly growing area are discussed. The knowledge synthesis presented in this review underscores the potential of mannose receptor-based targeted drug delivery as a promising avenue for advancing HIV treatment. By leveraging the unique properties of mannose receptors, researchers can design drug delivery systems that cater to individual needs, overcome existing limitations, and create more effective and patient-friendly treatments in the ongoing fight against HIV/AIDS. [Display omitted] [ABSTRACT FROM AUTHOR]

Dendrimers are covalently bonded globular nanostructures that may be used in the treatment of Alzheimer's disease (AD). Nowadays, AD therapies are focused on improving cognitive functioning and not causal treatment. However, this may change with the use of dendrimers, which are being investigated as a drug-delivery system or as a drug per se. With their ability to inhibit amyloid formation and their anti-tau properties, they are a promising therapeutic option for AD patients. Studies have shown that dendrimers may inhibit amyloid formation in at least two ways: by blocking fibril growth and by breaking already existing fibrils. Neurofibrillary tangles (NFTs) are abnormal filaments built by tau proteins that can be accumulated in the cell, which leads to the loss of cytoskeletal microtubules and tubulin-associated proteins. Cationic phosphorus dendrimers, with their anti-tau properties, can induce the aggregation of tau into amorphous structures. Drug delivery to mitochondria is difficult due to poor transport across biological barriers, such as the inner mitochondrial membrane, which is highly negatively polarized. Dendrimers may be potential nanocarriers and increase mitochondria targeting. Another considered use of dendrimers in AD treatment is as a drug-delivery system, for example, carbamazepine (CBZ) or tacrine. They can also be used to transport siRNA into neuronal tissue and to carry antioxidants and anti-inflammatory drugs to act protectively on the nervous system. [ABSTRACT FROM AUTHOR]

A new type of eco-friendly multifunctional dextran microbeads are synthesized for multiplexed assays. [Display omitted] There has been an increasing demand for simultaneous detection of multiple analytes in one sample. Microbead-based platforms have been developed for multiplexed assays. However, most of the microbeads are made of non-biodegradable synthetic polymers, leading to environmental and human health concerns. In this study, we developed an environmentally friendly dextran microbeads as a new type of multi-analyte assay platform. Biodegradable dextran was utilized as the primary material. Highly uniform magnetic dextran microspheres were successfully synthesized using the Shirasu porous glass (SPG) membrane emulsification technique. To enhance the amount of surface functional groups for ligand conjugation, we coated the dextran microbeads with a layer of dendrimers via a simple electrostatic adsorption process. Subsequently, a unique and efficient click chemistry coupling technique was developed for the fluorescence encoding of the microspheres, enabling multiplexed detection. The dextran microbeads were tested for 3-plex cytokine analysis, and exhibited excellent biocompatibility, stable coding signals, low background noise and high sensitivity. [ABSTRACT FROM AUTHOR]