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1.
Angew Chem Int Ed Engl ; 58(3): 796-800, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30474178

RESUMO

Prototypes of natural biosystems provide opportunities for artificial biomimetic systems to break the limits of natural reactions and achieve output control. However, mimicking unique natural structures and ingenious functions remains a challenge. Now, multiple biochemical reactions were integrated into artificially designed compartments via molecular assembly. First, multicompartmental silica nanoparticles with hierarchical structures that mimic the chloroplasts were obtained by a templated synthesis. Then, photoacid generators and ATPase-liposomes were assembled inside and outside of silica compartments, respectively. Upon light illumination, protons produced by a photoacid generator in the confined space can drive the liposome-embedded enzyme ATPase towards ATP synthesis, which mimics the photophosphorylation process in vitro. The method enables fabrication of bioinspired nanoreactors for photobiocatalysis and provides insight for understanding sophisticated biochemical reactions.

2.
J Colloid Interface Sci ; 487: 12-19, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27743541

RESUMO

Inspired by the composition of adhesive proteins in mussel, a facile, low-cost, and green approach to construct robust polydopamine (PDA) microcapsules as carriers for insulin delivery is developed. The morphology and shell thickness of the capsules could be tuned by varying the concentration of dopamine or the pH of Tris-HCl buffer. The PDA capsules are stable enough for long-term storage and transportation in practical application. The fluorescent property of PDA capsules labeled with FITC is beneficial in monitoring the safety and efficacy of drug carriers. Furthermore, the PDA shell coated insulin particles exhibit pH-responsive release behavior, making them promising for the oral administration of insulin in diabetic patients.


Assuntos
Materiais Biomiméticos/síntese química , Cápsulas/síntese química , Portadores de Fármacos , Indóis/síntese química , Insulina/química , Polímeros/síntese química , Animais , Bivalves/química , Tampões (Química) , Composição de Medicamentos , Liberação Controlada de Fármacos , Fluoresceína-5-Isotiocianato , Corantes Fluorescentes , Química Verde , Humanos , Concentração de Íons de Hidrogênio , Cinética
3.
J Colloid Interface Sci ; 490: 621-627, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27951512

RESUMO

We report an environmentally-responsible limited hydrothermal reaction to construct gram-scale MnO2 sponge-like hierarchical nanostructures composed of ultrathin nanosheets (∼5nm) in one pot. This template-free strategy simultaneously avoids the disposal of toxic materials and provides novel metal oxide nanostructures. As a typical application, the MnO2 hierarchical nanostructures prepared can easily remove positively-charged methylene blue in water with much more adsorption capacity than those of commercial carbon grain and MnO2 microparticles, TiO2 and Fe2O3 nanoparticles. Meanwhile, the solid-liquid separation is ready due to higher density resulted from their hierarchical nanostructures. Importantly adsorbed methylene blue can be reclaimed after elution with ethanol. Remarkably, the sponge-like hierarchical nanostructures can be recycled for many times with no obvious loss of adsorption capacity, qualifying them as a great potential application in environmental protection and resource reuse.

4.
Chem Rec ; 16(4): 1991-2004, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27311111

RESUMO

Advanced multifunctional microcapsules have revealed great potential in biomedical applications owing to their tunable size, shape, surface properties, and stimuli responsiveness. Polysaccharides are one of the most acceptable biomaterials for biomedical applications because of their outstanding virtues such as biocompatibility, biodegradability, and low toxicity. Many efforts have been devoted to investigating novel molecular design and efficient building blocks for polysaccharide-based microcapsules. In this Personal Account, we first summarize the common features of polysaccharides and the main principles of the design and fabrication of polysaccharide-based microcapsules, and further discuss their applications in biomedical areas and perspectives for future research.


Assuntos
Polissacarídeos/química , Cápsulas , Linhagem Celular Tumoral , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Humanos , Ligações de Hidrogênio , Concentração de Íons de Hidrogênio , Polissacarídeos/síntese química , Polissacarídeos/farmacologia
5.
ACS Nano ; 10(1): 556-61, 2016 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-26615669

RESUMO

Adenosine triphosphate (ATP) is one of the most important energy sources in living cells, which can drive serial key biochemical processes. However, generation of a proton gradient for ATP production in an artificial way poses a great challenge. In nature, photophosphorylation occurring in chloroplasts is an ideal prototype of ATP production. In this paper we imitate the light-to-ATP conversion process occurring in the thylakoid membrane by construction of FoF1-ATPase proteoliposome-coated PSII-based microspheres with well-defined core@shell structures using molecular assembly. Under light illumination, PSII can split water into protons, oxygen, and electrons and can generate a proton gradient for ATPase to produce ATP. Thus, an artificially designed chloroplast for PSII-driven ATP synthesis is realized. This biomimetic system will help to understand the photophosphorylation process and may facilitate the development of ATP-driven devices by remote light control.


Assuntos
Trifosfato de Adenosina/biossíntese , Materiais Biomiméticos/química , Complexo de Proteína do Fotossistema II/química , Proteolipídeos/química , ATPases Translocadoras de Prótons/química , Prótons , Materiais Biomiméticos/metabolismo , Cloroplastos/química , Cloroplastos/efeitos da radiação , Cloroplastos/ultraestrutura , Luz , Microesferas , Fotofosforilação/efeitos da radiação , Complexo de Proteína do Fotossistema II/metabolismo , Proteolipídeos/metabolismo , Proteolipídeos/ultraestrutura , ATPases Translocadoras de Prótons/metabolismo , Termodinâmica
6.
Nanoscale ; 7(25): 10908-11, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26055965

RESUMO

A new type of biohybrid photo-electrochemical cell was fabricated by layer-by-layer assembly of photosystem II and reduced graphene oxide. We demonstrate that the photocurrent in the direct electron transfer is enhanced about two fold with improved stability. The assembly strategy without any cross-linker or additional electron mediators makes the cell fabrication and operation much simpler as compared to previous approaches. This work may open new routes for the construction of solar energy conversion systems based on photoactive proteins and graphene materials.

7.
Nanoscale ; 7(1): 82-5, 2015 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-25254951

RESUMO

A smart self-powered cargo delivery system that is composed of creatine phosphate kinase (CPK) microspheres, kinesins and microtubules is demonstrated. The CPK microsphere not only acts as an ATP generation and buffering system, but also as a carrier for cargo transport, thus realizing the easy loading and self-powered delivery of cargos at the same time.


Assuntos
Preparações de Ação Retardada/química , Cinesina/química , Microtúbulos/química , Proteínas Motores Moleculares/química , Nanocápsulas/química , Robótica/métodos , Cinesina/ultraestrutura , Teste de Materiais , Microtúbulos/ultraestrutura , Proteínas Motores Moleculares/ultraestrutura , Movimento (Física) , Nanocápsulas/ultraestrutura , Tamanho da Partícula
8.
Nano Lett ; 14(11): 6160-4, 2014 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-25303630

RESUMO

LbL-assembled tubes were employed for micro/nanoscale cargo transportation through the kinesin-microtubule system. Selectively modified with kinesins onto the inner tube walls through Ni-NTA complexes, these tubes can work as channels for microtubules. A motility assay shows the smooth movement of microtubules along the tube inner wall powered by the inside immobilized kinesins. It could be envisioned that cargoes with different sizes can be transported through these tubular channels with little outside interruption.

9.
Chemistry ; 20(2): 499-504, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24307401

RESUMO

The preparation of 3D hierarchical nanostructures by a simple and versatile strategy of self-assembly of dopamine (DA) and phosphotungstic acid (PTA) is described. The size and morphology of the hierarchical nanostructures could be simply controlled by varying the ratio of the two components, their concentrations, and the pH of the initial Tris-HCl solution. The self-assembly of the flowerlike microspheres has been found to involve a two-stage growth process. Moreover, use of the hierarchical nanostructures as a possible carrier for an anticancer drug in chemotherapy has been explored. The nanostructures showed an intriguing pH-dependent release behavior, making them promising for applications in biomedical science.


Assuntos
Dopamina/química , Compostos de Tungstênio/química , Administração Oral , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/química , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Portadores de Fármacos , Concentração de Íons de Hidrogênio , Nanoestruturas
10.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 30(2): 189-94, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23568733

RESUMO

OBJECTIVE: To investigate the epidemiological status of glucose-6-phosphate dehydrogenase (G6PD) deficiency among children from Yunnan with unique ethnic origins. METHODS: DNA samples from 11759 children were tested with fluorescent spot test, G6PD/6PGD quantitative ratio assay and hemoglobin electrophoresis. RESULTS: The detection rate of G6PD deficiency was 2.5%, for which boys were significantly greater than girls (3.5% vs. 1.4%, P<0.05). Significant differences were also detected among children from different ethnic groups and different regions. For ethnic Han Chinese, the detection rate was 0.7%, which was lower than the majority of ethnic minorities. By regression analysis, altitude of residence and family history both have significant influence on the calculated rate. CONCLUSION: Occurrence of G6PD deficiency seems to be influenced by gender. It also varies substantially between different ethnic groups as well as regions, e.g., more common in south. It also showed a declining trend after years of diagnosis and intervention. This survey may provide a valuable basis for counseling of G6PD deficiency in Yunnan.


Assuntos
Deficiência de Glucosefosfato Desidrogenase/etnologia , Criança , Pré-Escolar , China/etnologia , Feminino , Deficiência de Glucosefosfato Desidrogenase/genética , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Masculino
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