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1.
Adv Mater ; : e2007719, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33598992

RESUMO

Combination chemotherapy refers to the use of multiple drugs to treat cancer. In this therapy, the optimal ratio of the drugs is essential to achieve drug synergism and the desired therapeutic effects. However, most delivery strategies are unable to precisely control the ratio of the drugs during the drug loading and delivery processes, resulting in inefficient synergy and unpredictable efficacy. Herein, a macrocyclic-amphiphile-based self-assembled nanoparticle (MASN) that achieves precise loading and ratiometric delivery of therapeutic combinations is presented. By integrating multiple macrocyclic cavities within a single nanoparticle, the MASN can load multiple drug molecules via the host-guest interaction, and the ratio of the drugs loaded can be predicted with their initial concentrations and characteristic binding affinity. Moreover, MASNs are readily degraded under a hypoxic microenvironment, allowing spontaneous release of the drugs upon reaching tumor tissues. With precise drug loading and controlled release mechanisms, MASNs achieve ratiometric delivery of multiple commercial drugs to tumors, thereby achieving optimal anti-tumor effects. Since the optimal drug ratio of a therapeutic combination can be quickly determined in vitro, MASNs can translate this optimal ratio to the therapeutic benefits in vivo, providing a potential platform for the rapid development of effective combination cancer therapies involving multiple drugs.

2.
J Mater Chem B ; 8(45): 10346-10352, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-32657318

RESUMO

One-dimensional (1D) morphology-unique Au-Ag2S nano-hybrids are achieved by combining the interfacial self-assembly of Ag nanowires, interface-oriented site-specific etching of Ag nanowires with AuCl4-, and the sulfurization of S2-. The as-formed Au-Ag2S nano-hybrid has a trough-like morphology. The wall of the Au-Ag2S nanotrough is a Ag2S/Au/Ag2S trilayer wall, but the Ag2S layer is a Ag2S-rich mixture of Ag2S and Au rather than pure Ag2S because of the diffusion of Au atoms towards Ag2S. The Au-Ag2S nanotrough shows strong absorption in the visible region (400-800 nm) and exhibits a favorable photoelectrochemical (PEC) response, the photocurrent of which is ∼8.5 times larger than that of pure Ag2S. This enhanced PEC response originates from the localized plasmonic resonance effect of Au. Moreover, the PEC biosensor based on the Au-Ag2S nanotroughs shows high sensitivity and selectivity, satisfactory reproducibility, and good stability towards human α-thrombin (TB) detection: a sensitive linear response ranging from 1.00 to 10.00 pmol L-1 and a low detection limit of 0.67 pmol L-1. This study provides a new model for studying the PEC behavior of plasmonic metal/semiconductor materials, and this Au-Ag2S nanotrough may also be useful in the fields of photocatalysis and photovoltaics.

3.
Chem Asian J ; 15(17): 2742-2748, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32658379

RESUMO

Although linker-free Au nanoparticle superstructures (AuNPSTs) have demonstrated to have satisfactory photothermal conversion efficiency owing to their enhanced visible-near-infrared absorption caused by the interparticle coupling, they cannot be used directly for in vivo photothermal therapy (PTT) of cancer because of poor stability. To address this issue, we herein propose a polymer-coating strategy, dressing AuNPST on a poly(dopamine) (PDA) coat, and successfully investigate the in vivo PTT effect of AuNPSTs. By employing Triton X-100 as an emulsifier for the formation of AuNPSTs, dopamine was site-specifically polymerized around each AuNPST by the interaction between -OH of Triton X-100 and -NH2 of dopamine. As-fabricated AuNPST/PDA has a sphere-like shape with an average diameter of ∼106 nm and the PDA shell is about 10 nm PDA thick. The AuNPST/PDA shows enhanced durability to heat, acid, and alkali compared with bare AuNPST. Also, under 808 nm laser irradiation, AuNPST/PDA shows photothermal conversion efficiency of ∼33%, higher than bare AuNPST (∼23%). Significantly, AuNPST/PDA can be used as in-vitro and in-vivo PTT agent and shows excellent therapeutic efficacy for tumor ablation thanks to its enhanced stability and biocompatibility, indicative of its potential practicability in clinical PTT.

4.
Angew Chem Int Ed Engl ; 59(31): 12684-12688, 2020 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-32253810

RESUMO

The oxidation of antioxidants by oxidizers imposes great challenges to both living organisms and the food industry. Here we show that the host-guest complexation of the carefully designed, positively charged, amphiphilic guanidinocalix[5]arene pentadodecyl ether (GC5A-12C) and negatively charged oleic acid (OA), a well-known cell membrane antioxidant, prevents the oxidation of the complex monolayers at the air-water interface from two potent oxidizers hydroxyl radicals (OH) and singlet delta oxygen (SDO). OH is generated from the gas phase and attacks from the top of the monolayer, while SDO is generated inside the monolayer and attacks amphiphiles from a lateral direction. Field-induced droplet ionization mass spectrometry results have demonstrated that the host-guest complexation achieves steric shielding and prevents both types of oxidation as a result of the tight and "sleeved in" physical arrangement, rather than the chemical reactivity, of the complexes.

5.
Chem Soc Rev ; 49(8): 2303-2315, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32181453

RESUMO

Classic prodrug strategies rely on covalent modification of active drugs to provide systems with superior pharmacokinetic properties than the parent drug and facilitate administration. Supramolecular chemistry is providing a new approach to developing prodrug-like systems, wherein the characteristics of a drug are modified in a beneficial manner by creating host-guest complexes that then permit the stimulus-induced release of the active species in a controlled manner. These complexes are termed "supramolecular prodrugs". In this review, we outline the concept of supramolecular drugs via host-guest chemistry and detail progress made in the area. This summary is designed to highlight the many advantages of supramolecular prodrugs, including ease-of-preparation, molecular-level protection, sensitive response to bio-stimuli, traceless release, and adaptability to different drugs. Limitations of the approach and opportunities for future growth are also detailed.

6.
Nat Commun ; 10(1): 5762, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31848349

RESUMO

Perfluorinated alkyl substances, such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), are toxic materials that are known to globally contaminate water, air, and soil resources. Strategies for the simultaneous detection and removal of these compounds are desired to address this emerging health and environmental issue. Herein, we develop a type of guanidinocalix[5]arene that can selectively and strongly bind to PFOS and PFOA, which we use to demonstrate the sensitive and quantitative detection of these compounds in contaminated water through a fluorescent indicator displacement assay. Moreover, by co-assembling iron oxide nanoparticle with the amphiphilic guanidinocalix[5]arene, we are able to use simple magnetic absorption and filtration to efficiently remove PFOS and PFOA from contaminated water. This supramolecular approach that uses both molecular recognition and self-assembly of macrocyclic amphiphiles is promising for the detection and remediation of water pollution.


Assuntos
Ácidos Alcanossulfônicos/análise , Calixarenos/química , Caprilatos/análise , Fluorcarbonetos/análise , Tensoativos/química , Poluentes Químicos da Água/análise , Absorção Fisico-Química , Ácidos Alcanossulfônicos/isolamento & purificação , Caprilatos/isolamento & purificação , Monitorização de Parâmetros Ecológicos/métodos , Poluição Ambiental/prevenção & controle , Compostos Férricos/química , Filtração/instrumentação , Filtração/métodos , Fluorcarbonetos/isolamento & purificação , Nanopartículas de Magnetita/química , Água/análise , Água/química , Poluentes Químicos da Água/isolamento & purificação , Poluição Química da Água/prevenção & controle
7.
Theranostics ; 9(16): 4624-4632, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31367245

RESUMO

Detection and quantification of trimethylamine N-oxide (TMAO), a metabolite from gut microbial, is important for the disease diagnosis such as atherosclerosis, thrombosis and colorectal cancer. In this study, a novel method was established for the sensing and quantitative detection of TMAO via molecular recognition of guanidinium-modified calixarene from complex matrix. Methods: Various macrocycles were tested for their abilities to serve as an artificial TMAO receptor. Using the optimized receptor, we developed an indicator displacement assay (IDA) for the facile fluorescence detection of TMAO. The quantification of TMAO was accomplished by the established calibration line after excluding the interference from the various interfering substances in artificial urine. Results: Among various macrocycles, water-soluble guanidinium-modified calix[5]arene (GC5A), which binds TMAO in submicromolar-level, was identified as the optimal artificial receptor for TMAO. With the aid of the GC5A•Fl (fluorescein) reporter pair, TMAO fluorescence "switch-on" sensing was achieved by IDA. The fluorescence intensity increased linearly with the elevated TMAO concentration. The detection was not significantly interfered by the various interfering substances. TMAO concentration in artificial urine was quantified using a calibration line with a detection limit of 28.88 ± 1.59 µM, within the biologically relevant low µM range. Furthermore, the GC5A•Fl reporter pair was successfully applied in analyzing human urine samples, by which a significant difference in fluorescence response was observed between the [normal + TMAO] and normal group. Conclusion: The proposed supramolecular approach provides a facile, low-cost and sensitive method for TMAO detection, which shows promise for tracking TMAO excretion in urine and studying chronic disease progression in humans.


Assuntos
Aterosclerose/diagnóstico , Calixarenos/análise , Microbioma Gastrointestinal/fisiologia , Metilaminas/análise , Fluorescência , Guanidina/química , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Fluorescência
8.
Beilstein J Org Chem ; 15: 1394-1406, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293689

RESUMO

We herein describe the comprehensive investigation of the complexation behavior of a guanidinium-modified calix[5]arene pentaisohexyl ether (GC5A) with a variety of typical luminescent dyes. Fluorescein, eosin Y, rose bengal, tetraphenylporphine sulfonate and sulfonated aluminum phthalocyanine were employed as classical aggregation-induced quenching dyes. 2-(p-Toluidinyl)naphthalene-6-sulfonic acid and 1-anilinonaphthalene-8-sulfonic acid were selected as representatives of intramolecular charge-transfer dyes. Phosphated tetraphenylethylene was involved as the classical aggregation-induced emission dye. Sulfonated acedan representing one example of two-photon fluorescent probes, was also investigated. A ruthenium(II) complex with carboxylated bipyridyl ligands was included as a representative candidate of luminescent transition-metal complexes. We determined the association constants of the GC5A-dye complexes by fluorescence titration and discuss the complexation-induced photophysical changes. In addition, a comparison of the complexation behavior of GC5A with that of other macrocycles and potential applications according to the diverse photophysical responses are provided.

9.
Theranostics ; 9(11): 3094-3106, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31244943

RESUMO

Gene therapy, with an important role in biomedicine, often requires vectors for gene condensation in order to avoid degradation, improve membrane permeation, and achieve targeted delivery. Macrocyclic molecules are a family of artificial receptors that can selectively bind a variety of guest species. Amphiphilic macrocycles, particularly those bearing cationic charges and their various assemblies represent a new class of promising non-viral vectors with intrinsic advantages in gene condensation and delivery. The most prominent examples include amphiphilic cyclodextrins, calixarenes and pillararenes. Herein, we systemically reviewed reported assemblies of amphiphilic macrocycles for gene delivery and therapy. The advantages and disadvantages of each type of macrocyclic amphiphiles for gene delivery, as well as the perspectives on the future development of this area are discussed.


Assuntos
DNA/metabolismo , Sistemas de Liberação de Medicamentos , Terapia Genética/métodos , Compostos Macrocíclicos/metabolismo , Nanomedicina/métodos , Tensoativos/metabolismo , Calixarenos/química , Calixarenos/metabolismo , Ciclodextrinas/química , Ciclodextrinas/metabolismo , Humanos , Compostos Macrocíclicos/química , Tensoativos/química
10.
Angew Chem Int Ed Engl ; 58(8): 2377-2381, 2019 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-30628146

RESUMO

Hypoxia plays crucial roles in many diseases and is a central target for them. Present hypoxia imaging is restricted to the covalent approach, which needs tedious synthesis. In this work, a new supramolecular host-guest approach, based on the complexation of a hypoxia-responsive macrocycle with a commercial dye, is proposed. To exemplify the strategy, a carboxyl-modified azocalix[4]arene (CAC4A) was designed that binds to rhodamine 123 (Rho123) and quenches its fluorescence. The azo groups of CAC4A were selectively reduced under hypoxia, leading to the release of Rho123 and recovery of its fluorescence. The noncovalent strategy was validated through hypoxia imaging in living cells treated with the CAC4A-Rho123 reporter pair.


Assuntos
Calixarenos/química , Fluorescência , Corantes Fluorescentes/química , Hipóxia , Imagem Óptica , Rodamina 123/química , Células A549 , Humanos , Estrutura Molecular
11.
Chem Commun (Camb) ; 54(52): 7227-7230, 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-29900455

RESUMO

Asymmetrical etching of nanoparticles was achieved by employing interface-confined galvanic replacement reactions. Interfacial Ag nanocubes, nanowires and nanospheres were fabricated into symmetry-reduced cubic, trough-like and spherical nanocups, respectively. The formation of nanocups is attributed to in situ local nanomasking and selective etching of interfacial nanoparticles at the single-nanoparticle level.

12.
Chem Sci ; 9(8): 2087-2091, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29675249

RESUMO

We designed a water-soluble guanidinium-modified calix[5]arene to target lysophosphatidic acid (LPA), an ideal biomarker for early diagnosis of ovarian and other gynecologic cancers, achieving binding on the nanomolar level. An indicator displacement assay, coupled with differential sensing, enabled ultrasensitive and specific detection of LPA. Moreover, we show that using a calibration line, the LPA concentration in untreated serum can be quantified in the biologically relevant low µM range with a detection limit of 1.7 µM. The reported approach is feasible for diagnosing ovarian and other gynecologic cancers, particularly at their early stages.

13.
Phys Chem Chem Phys ; 20(16): 10997-11002, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29629461

RESUMO

Cubic Pd nanocrystals (CPNCs) as one of typical nanostructures are generally fabricated using I- or Br- as capping ions. However, which ion, I- or Br-, exclusively mediates the growth of CPNCs in a given reaction system is not well understood. Herein, regardless of I- or Br- as the capping ion, we successfully achieved CPNCs in the same reaction system simply by adjusting the pH. Based on the Finke-Watzky kinetic model, an increase in pH accelerates the overall reduction rate of Pd2+, and the formation of CPNCs only occurs over the range of specific solution reduction rate constants (k1). This kinetically illuminates that the reduction rate of Pd2+ is the physicochemical parameter that determines which ion, I- or Br-, dictates the growth of CPNCs. Also, density functional theory (DFT) calculations further elucidate the dependence of the reduction rate of Pd2+ on pH and the configuration of the activated Pd2+ complex.

14.
J Am Chem Soc ; 140(14): 4945-4953, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29562139

RESUMO

Activatable phototheranostics is highly appealing to meet the demand of precision medicine. However, although it displays efficacy in the construction of activatable photosensitizers (PSs), direct covalent decoration still shows some inevitable issues, such as complex molecular design, tedious synthesis, possible photoactivity changes, and potential toxicity. Herein, we propose a novel concept of biomarker displacement activation (BDA) using host-guest strategy. To exemplify BDA, we engineered a PS-loaded nanocarrier by utilizing a macrocyclic amphiphile, where the fluorescence and photoactivity of PS were completely annihilated by the complexation of macrocyclic receptor (OFF state). When nanocarriers were accumulated into tumor tissues via the enhanced permeability and retention effect, the overexpressed biomarker adenosine triphosphates displaced PSs, accompanied by their fluorescence and photoactivity recovered (ON state). These reinstallations are unattainable in normal tissues, allowing us to concurrently achieve selective tumor imaging and targeted therapy in vivo. Compared with widely used covalent approach, the present BDA strategy provides the following advantages: (1) employment of approved PSs without custom covalent decoration; (2) traceless release of PSs with high fidelity by biomarker displacement; (3) adaptability to different PSs for establishing a universal platform and promised facile combination of diverse PSs to enhance photon utility in light window. Such a host-guest BDA strategy is easily amenable to other ensembles and targets, so that versatile biomedical applications can be envisaged.

15.
Chem Commun (Camb) ; 53(2): 392-395, 2016 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-27942622

RESUMO

A novel FRET platform was fabricated based on a macrocyclic amphiphile, reliant on the self-sorting complexation of a donor on the periphery of the assemblies and entrapment of an acceptor within the inner hydrophobic phase. By tuning subtly the donor/acceptor ratio, white light emission was successfully achieved with high quantum yield.


Assuntos
Luz , Compostos Macrocíclicos/síntese química , Tensoativos/síntese química , Transferência Ressonante de Energia de Fluorescência , Interações Hidrofóbicas e Hidrofílicas , Compostos Macrocíclicos/química , Estrutura Molecular , Tamanho da Partícula , Teoria Quântica , Propriedades de Superfície , Tensoativos/química , Água/química
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