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1.
Org Biomol Chem ; 22(33): 6810-6821, 2024 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-39113548

RESUMO

Nucleic acids (DNA and RNA) can form diverse secondary structures ranging from hairpins to duplex, triplex, G4-tetraplex and C4-i-motifs. Many of the DNA analogues designed as antisense oligonucleotides (ASO) are also adept at embracing such folded structures, although to different extents with altered stabilities. One such analogue, peptide nucleic acid (PNA), which is uncharged and achiral, forms hybrids with complementary DNA/RNA with greater stability and specificity than DNA:DNA/RNA hybrids. Like DNAs, these single-stranded PNAs can form PNA:DNA/RNA duplexes, PNA:DNA:PNA triplexes, PNA-G4 tetraplexes and PNA-C4-i-motifs. We have recently designed Janus-like bimodal PNAs endowed with two different nucleobase sequences on either side of a single aminoethylglycyl (aeg) PNA backbone and shown that these can simultaneously bind to two complementary DNA sequences from both faces of PNA. This leads to the formation of supramolecular polyplexes such as double duplexes, triple duplexes and triplexes of double duplexes with appropriate complementary DNA/RNA. Herein, we demonstrate that Janus/bimodal PNA with a poly G-sequence on the triazole side of the PNA backbone and mixed bases on the t-amide side, templates the initial formation of a (PNA-G5)4 tetraplex (triazole side), followed by the formation of a PNA:DNA duplex (t-amide side). Such a polyplex shows synergistic overall stabilisation compared to the isolated duplexes/quadruplex. The assembly of polyplexes with a shared backbone for duplexes and tetraplexes is programmable and may have potential applications in the self-assembly of nucleic acid nano- and origami structures. It is also shown that Janus PNAs enter the cells better than the standard aeg-PNA oligomers, and hence have implications for in vivo applications as well.


Assuntos
DNA , Quadruplex G , Ácidos Nucleicos Peptídicos , Ácidos Nucleicos Peptídicos/química , DNA/química , Humanos , Substâncias Macromoleculares/química , Substâncias Macromoleculares/síntese química
3.
J Mater Chem B ; 12(30): 7292-7297, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39016812

RESUMO

Chirality is one of the hallmarks of biomolecules. Herein, we utilize heparin, a chiral biomolecule and potent drug, to induce chiral organization into the assembly of an achiral molecule. Polyanionic heparin binds with a dicationic perylenediimide derivative to induce supramolecular helical organization in aqueous medium as well as in a highly competitive cell culture medium.


Assuntos
Heparina , Imidas , Perileno , Heparina/química , Imidas/química , Perileno/química , Perileno/análogos & derivados , Estereoisomerismo , Humanos , Estrutura Molecular , Substâncias Macromoleculares/química , Substâncias Macromoleculares/síntese química
4.
ACS Appl Bio Mater ; 7(8): 5609-5621, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39074362

RESUMO

α-Ketoglutaric acid-based supramolecular Zn(II) metallogels in N,N'-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) solvent (i.e., Zn-α-Glu-DMF and Zn-α-Glu-DMSO) were successfully achieved. Zinc(II) acetate salt and α-ketoglutaric acid directed a three-dimensional noncovalent supramolecular network individually entrapped with N,N'-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) solvent to accomplish their respective semisolid flexible metallogel frameworks. The gel features of these synthesized materials were verified by rheological experiments such as amplitude sweep and frequency sweep measurements. The discrete morphological arrangements were analyzed for these metallogel samples through field emission scanning electron microscopic (FESEM) analysis. Highly stacked interconnected blocks of Zn-α-Glu-DMF with hierarchical arrays are found due to the occurrence of diverse noncovalent supramolecular interactions present in the metallogel framework. A distinct spherical shaped microstructure with interconnected hierarchical assembly has been observed for the FESEM pattern of Zn-α-Glu-DMSO. FTIR spectroscopic measurement was carried out to detect some important stretching vibrations of xerogel samples of different metallogels as well as gel-constructing chemical ingredients. A substantial amount of peak shifting of xerogel samples for both metallogels is observed in FTIR analysis, indicating the presence of different noncovalent interactions. ESI-mass analysis portrays a possible metallogel-constructing strategy. The antibacterial potentialities of both metallogels were investigated. These materials exhibited good antimicrobial efficacy toward Gram-positive and Gram-negative bacterial strains (including Escherichia coli, Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, and Salmonella typhimurium). Both synthesized metallogels were successfully implemented to fabricate the photoresponsive semiconducting diode. These materials offer excellent photodiode parameters including an ideality factor and rectification ratio (ON/OFF ratio). Synthesized metallogels are used to successfully fabricate photodiodes with an Al/p-Si/metallogel/Au structure. The ideality factors (η) for Zn-α-Glu-DMF and Zn-α-Glu-DMSO are found as 1.3 and 2.3, respectively, in dark conditions. The rectification ratios for Zn-α-Glu-DMF and Zn-α-Glu-DMSO metallogels are also determined, and these are found as 40 and 10, respectively.


Assuntos
Antibacterianos , Materiais Biocompatíveis , Géis , Teste de Materiais , Testes de Sensibilidade Microbiana , Solventes , Zinco , Zinco/química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Géis/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/síntese química , Solventes/química , Tamanho da Partícula , Semicondutores , Substâncias Macromoleculares/química , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/farmacologia
5.
J Mater Chem B ; 12(29): 6996-7000, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38949321

RESUMO

We show distinct CH-π interactions and assembly pathways for the amphiphile N-(fluorenylmethoxycarbonyl)-galactosamine and its epimer N-(fluorenylmethoxycarbonyl)-glucosamine. These differences result in the formation of supramolecular nanofibrous systems with opposite chirality. Our results showcase the importance of the carbohydrates structural diversity for their specific biointeractions and the opportunity that their ample interactome offers for synthesis of versatile and tunable supramolecular (bio) materials.


Assuntos
Tensoativos , Estereoisomerismo , Tensoativos/química , Tensoativos/síntese química , Carboidratos/química , Galactosamina/química , Glucosamina/química , Glucosamina/análogos & derivados , Substâncias Macromoleculares/química , Substâncias Macromoleculares/síntese química , Nanofibras/química
6.
Int J Biol Macromol ; 273(Pt 2): 132775, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823732

RESUMO

A novel flame retardant containing Si, N, and S elements, ((2-(triethoxysilyl)ethyl)thio)ethan-1-amine hydrochloride (TETEA), was synthesized via a click reaction and characterized using nuclear magnetic resonance spectroscopy (NMR) and fourier transform infrared spectroscopy (FTIR). Subsequently, the flame-retardant cotton fabric was fabricated by sol-gel method. The results indicated that TETEA was successfully loaded on cotton fabric and formed a uniform protective layer on the surface of cotton fabric, exhibiting excellent flame retardancy. The flame-retardant cotton fabric achieved limiting oxygen index (LOI) of 28.3 % and passed vertical combustion test without after-flame or afterglow time at TETEA concentration of 500 g/L. Thermogravimetric analysis revealed that the residual carbon content of the flame-retardant cotton fabric was much higher than that of the control under air and N2 conditions. Besides, the flame-retardant cotton fabric was not ignited in cone calorimeter test with an external heat flux of 35 kW/m2. The peak heat release rate and the total heat release decreased from 133.4 kW/m2 to 25.8 kW/m2 and from 26.46 MJ/m2 to 17.96 MJ/m2, respectively. This phosphorus-free flame retardant offers a simplified synthesis process without adverse environmental impacts, opening up a new avenue for the development environmentally friendly flame retardants compared to traditional alternatives.


Assuntos
Celulose , Fibra de Algodão , Retardadores de Chama , Retardadores de Chama/síntese química , Retardadores de Chama/análise , Fibra de Algodão/análise , Celulose/química , Celulose/análogos & derivados , Nitrogênio/química , Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Substâncias Macromoleculares/química , Substâncias Macromoleculares/síntese química
7.
J Mater Chem B ; 12(25): 6146-6154, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38842181

RESUMO

Supramolecular polymers (SPs) are an emerging class of drug transporters employed to improve drug therapy. Through the rational design of self-assembling monomers, one can optimize the properties of the resulting supramolecular nanostructures, such as size, shape, surface chemistry, release, and, therefore, biological fates. This study highlights the design of isomeric SN38 prodrugs through the conjugation of hydrophilic oligo(ethylene glycol) (OEG) with hydroxyls at positions 10 and 20 on hydrophobic SN-38. Self-assembling prodrug (SAPD) isomers 10-OEG-SN38 and 20-OEG-SN38 can self-assemble into giant nanotubes and filamentous assemblies, respectively, via aromatic associations that dominate self-assembly. Our study reveales the influence of modification sites on the assembly behavior and ability of the SN38 SAPDs, as well as drug release and subsequent in vitro and in vivo antitumor effects. The SAPD modified at position 20 exhibits stronger π-π interactions among SN38 units, leading to more compact packing and enhanced assembly capability, whereas OEG at position 10 poses steric hindrance for aromatic associations. Importantly, owing to its higher chemical and supramolecular stability, 20-OEG-SN38 outperforms 10-OEG-SN38 and irinotecan, a clinically used prodrug of SN38, in a CT26 tumor model, demonstrating enhanced tumor growth inhibition and prolonged animal survival. This study presents a new strategy of using interactions among drug molecules as dominating features to create supramolecular assemblies. It also brings some insights into creating effective supramolecular drug assemblies via the engineering of self-assembling building blocks, which could contribute to the optimization of design principles for supramolecular drug delivery systems.


Assuntos
Irinotecano , Pró-Fármacos , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Pró-Fármacos/síntese química , Irinotecano/química , Irinotecano/farmacologia , Humanos , Animais , Camundongos , Isomerismo , Proliferação de Células/efeitos dos fármacos , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Substâncias Macromoleculares/química , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Polietilenoglicóis/química , Camptotecina/química , Camptotecina/farmacologia , Camptotecina/análogos & derivados , Camundongos Nus
8.
Chem Asian J ; 19(17): e202400344, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38822687

RESUMO

A novel inorganic-organic-inorganic ternary bioactive material formulated on antimicrobial peptide-based polymer has been reported. Supramolecular approach has been employed to incorporate molecularly crowded tyrosine-based polymer stabilized silver nanoparticles into membrane bound vesicles exploiting polyoxometalate-triggered surface templating strategy. Utilizing the covalent reversible addition fragmentation chain transfer (RAFT) polymerization and exploiting templated supramolecular architectonics at biopolymer interface, the bioactive ternary polymeric nanohybrids have been designed against Shigellosis leveraging the antibacterial activities of silver nanoparticle, cationic amphiphilic tyrosine polymer and inorganic polyoxometalate. The detail investigation against Shigella flexneri 2a cell line demonstrates that the collaborative mechanism of the ternary hybrid composite enhances the bactericidal activity in comparison to only polyoxometalate and polymer stabilized silver nanoparticle with an altered mechanism of action which is established via detailed biological analysis.


Assuntos
Antibacterianos , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Polímeros , Prata , Compostos de Tungstênio , Prata/química , Prata/farmacologia , Nanopartículas Metálicas/química , Compostos de Tungstênio/química , Compostos de Tungstênio/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Polímeros/química , Polímeros/farmacologia , Polímeros/síntese química , Shigella flexneri/efeitos dos fármacos , Shigella flexneri/química , Humanos , Linhagem Celular , Substâncias Macromoleculares/química , Substâncias Macromoleculares/farmacologia , Substâncias Macromoleculares/síntese química
9.
Chem Asian J ; 19(17): e202400419, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38872363

RESUMO

Supramolecular gels are an important class of materials that are promising for its wide range of applications including drug delivery. While supramolecular gels are intrinsically porous because of the 3D nano-matrix (gel matrix) that is being formed due to supramolecular self-assembly process involving the gelator molecules during gelation, additional nanopores can be introduced to the overall gel if the gelator molecule itself holds molecular cavity such as metal-organic-cage (MOC) molecules. A MOC having the molecular formula [(Pd2L24).4NO3].3H2O.2DMF.MeOH (Pd-cage) (L2=5-Azido-N,N'-di-pyridin-3-yl-isophthalamide) was successfully synthesized and characterized by FT-IR, 1H NMR, ESI-MS and single crystal X-ray diffraction. Stimuli-reversible supramolecular metallogel PdG could easily be formed from Pd-cage in DMSO/water mixture. The molecular cage of Pd-cage was demonstrated to be available for loading an anti-cancer drug namely doxorubicin (DOX). Subsequently, DOX was also loaded within PdG and delivered to melanoma cell line B16-F10 displaying significant anti-cancer activity as revealed by both MTT and scratch assay. Rheoreversibility of PdG and its ability to load and deliver DOX to cancer cells clearly raised hope for developing this metallogel further as topical anticancer gel.


Assuntos
Doxorrubicina , Géis , Géis/química , Camundongos , Animais , Doxorrubicina/farmacologia , Doxorrubicina/química , Paládio/química , Paládio/farmacologia , Linhagem Celular Tumoral , Portadores de Fármacos/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Proliferação de Células/efeitos dos fármacos , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/patologia , Substâncias Macromoleculares/química , Substâncias Macromoleculares/farmacologia , Substâncias Macromoleculares/síntese química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos
10.
Macromol Rapid Commun ; 45(15): e2400141, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38695257

RESUMO

Reversible addition-fragmentation chain transfer (RAFT) emulsion polymerization of methyl methacrylate (MMA) is successfully performed in water in the presence of a poly(methacrylic acid) (PMAA) macromolecular chain transfer agent (macroCTA) leading to the formation of self-stabilized PMAA-b-PMMA amphiphilic block copolymer particles. At pH 3.7, the reactions are well-controlled with narrow molar mass distributions. Increasing the initial pH, particularly above 5.6, results in a partial loss of reactivity of the PMAA macroCTA. The effect of the degree of polymerization (DPn) of the PMMA block, the solids content, the nature of the hydrophobic segment, and the pH on the morphology of the obtained diblock copolymer particles is then investigated. Worm-like micelles are formed for a DPn of PMMA of 20 (PMMA20), while "onion-like" particles and spherical vesicles are obtained for PMMA30 and PMMA50, respectively. In contrast, spherical particles are obtained for the DPns higher than 150. This unusual evolution of particle morphologies upon increasing the DPn of the PMMA block seems to be related to hydrogen bonds between hydrophilic MAA and hydrophobic MMA units.


Assuntos
Emulsões , Metilmetacrilato , Polimerização , Ácidos Polimetacrílicos , Emulsões/química , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/síntese química , Metilmetacrilato/química , Substâncias Macromoleculares/química , Substâncias Macromoleculares/síntese química , Interações Hidrofóbicas e Hidrofílicas , Polimetil Metacrilato/química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Estrutura Molecular , Micelas
11.
J Am Chem Soc ; 146(21): 14844-14855, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38747446

RESUMO

Nature employs sophisticated mechanisms to precisely regulate self-assembly and functions within biological systems, exemplified by the formation of cytoskeletal filaments. Various enzymatic reactions and auxiliary proteins couple with the self-assembly process, meticulously regulating the length and functions of resulting macromolecular structures. In this context, we present a bioinspired, reaction-coupled approach for the controlled supramolecular polymerization in synthetic systems. To achieve this, we employ an enzymatic reaction that interfaces with the adenosine triphosphate (ATP)-templated supramolecular polymerization of naphthalene diimide monomers (NSG). Notably, the enzymatic production of ATP (template) plays a pivotal role in facilitating reaction-controlled, cooperative growth of the NSG monomers. This growth process, in turn, provides positive feedback to the enzymatic production of ATP, creating an ideal reaction-coupled assembly process. The success of this approach is further evident in the living-growth characteristic observed during seeding experiments, marking this method as the pioneering instance where reaction-coupled self-assembly precisely controls the growth kinetics and structural aspects of supramolecular polymers in a predictive manner, akin to biological systems.


Assuntos
Trifosfato de Adenosina , Imidas , Naftalenos , Polimerização , Naftalenos/química , Naftalenos/metabolismo , Naftalenos/síntese química , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/química , Imidas/química , Substâncias Macromoleculares/química , Substâncias Macromoleculares/metabolismo , Substâncias Macromoleculares/síntese química , Estrutura Molecular , Cinética , Polímeros/química
12.
ACS Appl Bio Mater ; 7(6): 3777-3785, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38754861

RESUMO

Oral devices, such as foil-type devices, show great potential for the delivery of poorly permeable macromolecules by enabling unidirectional release of the loaded pharmaceutical composition in close proximity to the epithelium in the small intestine or colon. However, one of the primary concerns associated with the use of foil-type devices so far has been the utilization of nonbiodegradable elastomers in the fabrication of the devices. Therefore, research into biodegradable substitute materials with similar characteristics enables drug delivery in a sustainable and environmentally friendly manner. In this study, a biodegradable elastomer, polyoctanediol citrate (POC), was synthesized via a one-pot reaction, with subsequent purification and microscale pattern replication via casting. The microstructure geometry was designed to enable fabrication of foil-type devices with the selected elastomer, which has a high intrinsic surface free energy. The final elastomer was demonstrated to have an elastic modulus ranging up to 2.2 ± 0.1 MPa, with strain at failure up to 110.1 ± 1.5%. Devices were loaded with acetaminophen and enterically coated, demonstrating 100% release at 2.5 h, following dissolution for 1 h in 0.1 M hydrochloric acid and 1.5 h in pH 6.8 phosphate-buffered saline. The elastomer demonstrated promising properties based on mechanical testing, surface free energy evaluation, and degradation studies.


Assuntos
Materiais Biocompatíveis , Elastômeros , Teste de Materiais , Tamanho da Partícula , Elastômeros/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/síntese química , Sistemas de Liberação de Medicamentos , Humanos , Acetaminofen/química , Acetaminofen/administração & dosagem , Administração Oral , Citratos/química , Substâncias Macromoleculares/química , Substâncias Macromoleculares/síntese química , Polímeros/química
13.
J Mater Chem B ; 12(19): 4666-4672, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38647183

RESUMO

The formation of transient structures plays important roles in biological processes, capturing temporary states of matter through influx of energy or biological reaction networks catalyzed by enzymes. These natural transient structures inspire efforts to mimic this elegant mechanism of structural control in synthetic analogues. Specifically, though traditional supramolecular materials are designed on the basis of equilibrium formation, recent efforts have explored out-of-equilibrium control of these materials using both direct and indirect mechanisms; the preponderance of such works has been in the area of low molecular weight gelators. Here, a transient supramolecular hydrogel is realized through cucurbit[7]uril host-guest physical crosslinking under indirect control from a biocatalyzed network that regulates and oscillates pH. The duration of transient hydrogel formation, and resulting mechanical properties, are tunable according to the dose of enzyme, substrate, or pH stimulus. This tunability enables control over emergent functions, such as the programmable burst release of encapsulated model macromolecular payloads.


Assuntos
Hidrocarbonetos Aromáticos com Pontes , Hidrogéis , Imidazóis , Hidrogéis/química , Hidrogéis/síntese química , Concentração de Íons de Hidrogênio , Imidazóis/química , Hidrocarbonetos Aromáticos com Pontes/química , Substâncias Macromoleculares/química , Substâncias Macromoleculares/síntese química , Biocatálise , Estrutura Molecular , Muramidase/química , Muramidase/metabolismo
14.
Int J Biol Macromol ; 268(Pt 2): 131724, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38653427

RESUMO

The emergence of novel well-defined biological macromolecular architectures containing fluorine moieties displaying superior functionalities can satisfactorily address many biomedical challenges. In this research, ABA- and AB-type glucose-based biological macromolecules were synthesized using acryl-2,3,4,6-tetra-O-acetyl-D-glucopyranoside with pentafluorophenyl (FPM), pentafluorobenzyl (FBM), phenyl (PM) and benzyl (BM) methacrylate-based macro-RAFT agents following RAFT polymerization. The macro-RAFT agents and the corresponding copolymers were characterized by 19F, 1H, and 13C NMR and FTIR spectroscopic techniques to understand the chemical structure, molecular weight by size-exclusion chromatography, thermal analysis by TGA and DSC. Thermal stability (Td5%) of the FPM and FBM fluoro-based polymers was observed in the range of 219-267 °C, while the non-fluoro PM and BM polymers exhibited in the range of 216-264 °C. Among the macro-RAFT agents, PFPM (107 °C, ΔH: 0.613 J/g) and PPM (103 °C, ΔH: 0.455 J/g) showed higher Tm values, while among the block copolymers, PFBM-b-PG (123 °C, ΔH: 0.412 J/g) and PG-b-PFPM-b-PG (126 °C, ΔH: 0.525 J/g) exhibited higher Tm values. PFBMT and PPM macro-RAFT agents, PPM-b-PG and PG-b-PPM-b-PG copolymer spin-coated films showed the highest hydrophobicity (120°) among the synthesized polymers. The block copolymers exhibited self-assembled segregation by using relatively hydrophobic segments as the core and hydrophilic moieties as the corona. Synthesized biological macromolecules exhibit maximum antibacterial activity towards S. aureus than E. coli bacteria. Fluorophenyl (PFPM) and non-fluorobenzyl-based (PBMT) macro-RAFT agents exhibit low IC50 values, suggesting high cytotoxicity. All the triblock copolymers exhibit lesser cytotoxicity than the di-block polymers.


Assuntos
Glucose , Substâncias Macromoleculares , Glucose/química , Substâncias Macromoleculares/química , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Polímeros/química , Polímeros/síntese química , Polímeros/farmacologia , Humanos , Polimerização , Peso Molecular , Flúor/química , Técnicas de Química Sintética
15.
J Am Chem Soc ; 146(18): 12577-12586, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38683934

RESUMO

Dynamic supramolecular assemblies, driven by noncovalent interactions, pervade the biological realm. In the synthetic domain, their counterparts, supramolecular polymers, endowed with remarkable self-repair and adaptive traits, are often realized through bioinspired designs. Recently, controlled supramolecular polymerization strategies have emerged, drawing inspiration from protein self-assembly. A burgeoning area of research involves mimicking the liquid-liquid phase separation (LLPS) observed in proteins to create coacervate droplets and recognizing their significance in cellular organization and diverse functions. Herein, we introduce a novel perspective on synthetic coacervates, extending beyond their established role in synthetic biology as dynamic, membraneless phases to enable structural control in synthetic supramolecular polymers. Drawing parallels with the cooperative growth of amyloid fibrils through LLPS, we present metastable coacervate droplets as dormant monomer phases for controlled supramolecular polymerization. This is achieved via a π-conjugated monomer design that combines structural characteristics for both coacervation through its terminal ionic groups and one-dimensional growth via a π-conjugated core. This design leads to a unique temporal LLPS, resulting in a metastable coacervate phase, which subsequently undergoes one-dimensional growth via nucleation within the droplets. In-depth spectroscopic and microscopic characterization provides insights into the temporal evolution of disordered and ordered phases. Furthermore, to modulate the kinetics of liquid-to-solid transformation and to achieve precise control over the structural characteristics of the resulting supramolecular polymers, we invoke seeding in the droplets, showcasing living growth characteristics. Our work thus opens up new avenues in the exciting field of supramolecular polymerization, offering general design principles and controlled synthesis of precision self-assembled structures in confined environments.


Assuntos
Polimerização , Substâncias Macromoleculares/química , Substâncias Macromoleculares/síntese química , Polímeros/química , Polímeros/síntese química , Extração Líquido-Líquido/métodos , Estrutura Molecular , Separação de Fases
16.
Macromol Rapid Commun ; 45(13): e2300737, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38521991

RESUMO

Near-infrared (NIR)-triggered shape memory hydrogels with promising mechanical strength hold immense potential in the field of biomedical applications and soft actuators. However, the optical and mechanical properties of currently reported hydrogels usually suffer from limited solubility and dispersion of commonly used photothermal additives in hydrogels, thus restricting their practical implementations. Here,, a set of NIR-responsive shape memory hydrogels synthesized by polyaddition of diisocyanate-terminated poly(ethylene glycol), imidazolidinyl urea (IU), and p-benzoquinone dioxime (BQDO) is reported. The introduction of IU, a hydrogen bond reinforcing factor, significantly enhances the mechanical properties of the hydrogels, allowing for their tunable ranges of the ultimate tensile strength (0.4-2.5 MPa), elongation at break (210-450%), and Young's modulus (190-850 kPa). The unique hydrogels exhibit an intrinsic photothermal effect because of the covalently incorporated photothermal moiety (BQDO), and the photothermal supramolecular hydrogel shows controllable shape memory capabilities characterized by rapid recovery speed and high recovery ratio (>90%). This design provides new possibilities for applying shape memory hydrogels in the field of soft actuators.


Assuntos
Hidrogéis , Raios Infravermelhos , Hidrogéis/química , Hidrogéis/síntese química , Polietilenoglicóis/química , Estrutura Molecular , Resistência à Tração , Ureia/química , Substâncias Macromoleculares/química , Substâncias Macromoleculares/síntese química , Materiais Inteligentes/química
17.
Mikrochim Acta ; 189(3): 98, 2022 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-35147785

RESUMO

Laccases are multicopper proteins for dioxygen-involved oxidation of a broad spectrum of organic compounds. I Novel amyloid-like phenylalanine-Cu (F-Cu(II)) fibrils were developed, which were obtained via supramolecular self-assembly of Cu2+ and phenylalanine (F) under basic condition. The obtained amyloid-like fibrils represented highly periodic structure, of which the lattice unit was constructed via alternating hydrophobic (aromatic environment) and hydrophilic (both hydrogen bonding and Cu(II) coordination) interactions. Relative to natural laccases, the amyloid-like F-Cu(II) architecture exhibited comparable substrate affinity (Michaelis constant, Km = 0.75 mM) and higher catalytic efficiency (kcat/Km = 773.33 × 10-3 g-1 min-1L). Moreover, it exhibited remarkable tolerances in pH (4 ~ 10), temperature (room temperature ~ 200 ℃), organic solvent, and long-term storage (> 15 days). These stabilities were superior among the reported nature and artificial laccases, presenting a more promising candidate in various chemo- or bio-applications. In addition, F-Cu(II) fibrils could catalyze the oxidation of dopamine (DA) to a brown product, in which a new absorption band at 470 nm was observed. Based on this, a simple colorimetric assay for the detection of DA could be performed. We reported a novel amyloid-like phenylalanine-Cu fibrils, in which F-Cu+ complex can mimick the T1 site of natural laccase to oxidize the substrates. Then electrons transferred to F-Cu2+ complex via N-H···O=C hydrogen binding pathway. Finally, the dioxygen was transformed to water though radical reaction.


Assuntos
Cobre/química , Dopamina/análise , Fenilalanina/química , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química
18.
Org Biomol Chem ; 20(7): 1488-1492, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35103273

RESUMO

A novel method for lactam stapling of Asp/Lys-containing peptides has been developed that does not require coupling agents. A backbone thioamide is incorporated at the N-terminal side of the aspartate residue. Ag(I)-promoted activation of the thioamide in the vicinity of the Asp carboxylate generates a cyclic isoimide intermediate that is trapped by the Lys amine to generate the macrolactam. This method is suitable for generation of i,i+2, i,i+3, and i,i+4-spaced lactam-bridged peptides.


Assuntos
Lactamas/química , Substâncias Macromoleculares/síntese química , Peptídeos Cíclicos/síntese química , Tioamidas/química , Substâncias Macromoleculares/química , Estrutura Molecular , Peptídeos Cíclicos/química
19.
ACS Appl Mater Interfaces ; 14(3): 4417-4422, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35005883

RESUMO

Near-infrared (NIR) targeted cell imaging has become a research hotspot due to the advantages of deeper tissue penetration, minimal interference from the background signals, and lower light damage. Herein, we report a multivalent supramolecular aggregate with NIR fluorescence emission, which was fabricated from triphenylamine derivatives (TPAs), cucurbit[8]uril (CB[8]), Si-rhodamine (SiR), and hyaluronic acid (HA). Interestingly, possessing a rigid luminescent core and cationic phenylpyridinium units linked by flexible alkyl chains, the tripaddle hexacationic TPA could bind with CB[8] at a 2:3 stoichiometric ratio to form a network-like multivalent assembly with enhanced red luminescence. Such organic two-dimensional network-like aggregate further co-assembled with the energy acceptor SiR and cancer cell targeting agent HA, leading to nanoparticles with NIR emission at 675 nm via an intermolecular energy transfer pathway. Furthermore, the obtained multivalent supramolecular aggregate was successfully applied in lysosome targeted imaging toward A549 cancer cells, which provides a convenient strategy for NIR targeted cell imaging.


Assuntos
Compostos de Anilina/química , Materiais Biocompatíveis/química , Imagem Óptica , Células A549 , Compostos de Anilina/síntese química , Materiais Biocompatíveis/síntese química , Humanos , Raios Infravermelhos , Lisossomos/química , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Teste de Materiais
20.
ACS Appl Mater Interfaces ; 14(2): 2464-2477, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35045602

RESUMO

Nanomedicine, constructed from therapeutics, presents an advantage in drug delivery for cancer therapies. However, nanocarrier-based treatment systems have problems such as interbatch variability, multicomponent complexity, poor drug delivery, and carrier-related toxicity. To solve these issues, the natural molecule honokiol (HK), an anticancer agent in a phase I clinical trial (CTR20170822), was used to form a self-assembly nanoparticle (SA) through hydrogen bonding and hydrophobicity. The preparation of SA needs no molecular precursors or excipients in aqueous solution, and 100% drug-loaded SA exhibited superior tumor-targeting ability due to the enhanced permeability and retention (EPR) effect. Moreover, SA significantly enhanced the antitumor immunity relative to free HK, and the mechanism has notable selectivity to the p53 pathway. Furthermore, SA exhibited excellent physiological stability and inappreciable toxicity. Taken together, this supramolecular self-assembly strategy provides a safe and "molecular economy" model for rational design of clinical therapies and is expected to promote targeted therapy of HK, especially in colorectal cancer patients with obvious p53 status.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Materiais Biocompatíveis/farmacologia , Compostos de Bifenilo/farmacologia , Neoplasias Colorretais/terapia , Imunoterapia , Lignanas/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Proteína Supressora de Tumor p53/antagonistas & inibidores , Animais , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Compostos de Bifenilo/síntese química , Compostos de Bifenilo/química , Neoplasias Colorretais/imunologia , Feminino , Humanos , Lignanas/síntese química , Lignanas/química , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Teste de Materiais , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estrutura Molecular , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/terapia , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/imunologia
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