22,027 results match your criteria pore size

Effect of Polymer Source on In Vitro Drug Release from PLGA Microspheres.

Int J Pharm 2021 Jul 28:120907. Epub 2021 Jul 28.

University of Connecticut, Department of Pharmaceutical Sciences, Storrs, CT 06269.

Determination of the qualitative (Q1) sameness of poly (lactic-co-glycolic acid) (PLGA) polymers can be very challenging due to PLGA being a random copolymer with inherent heterogeneity. Performance variation of PLGA microsphere drug product as a result of altered PLGA characteristics has been recognized as a critical limiting factor in product development. It has been reported that PLGA characteristics and degradation profiles are sensitive to minor differences in the manufacturing and control processes. Read More

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A new Fe-C porous filter material from dredged sediment: preparation, characterization, and its application.

Environ Sci Pollut Res Int 2021 Jul 31. Epub 2021 Jul 31.

National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Wenzhou University, Wenzhou, 325035, China.

A new Fe-C porous filter material was prepared with dredged sediment of river as raw material. The orthogonal test L(3) and component ratio experiment of raw material were conducted to investigate the optimum technological condition. Further, the filter obtained was characterized by Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), energy dispersive X-ray spectroscope (EDS), and X-ray diffraction (XRD). Read More

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Unidirectional ion transport in nanoporous carbon membranes with a hierarchical pore architecture.

Nat Commun 2021 Jul 30;12(1):4650. Epub 2021 Jul 30.

Department of Biomedical Engineering, Southern University of Science and Technology (SUSTech), Shenzhen, China.

The transport of fluids in channels with diameter of 1-2 nm exhibits many anomalous features due to the interplay of several genuinely interfacial effects. Quasi-unidirectional ion transport, reminiscent of the behavior of membrane pores in biological cells, is one phenomenon that has attracted a lot of attention in recent years, e.g. Read More

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Sodium hypochlorite and Cu-O-Mn/ columnar activated carbon catalytic oxidation for treatment of ultra-high concentration polyvinyl alcohol wastewater.

Chemosphere 2021 Jul 13;285:131526. Epub 2021 Jul 13.

The State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu, 610065, China. Electronic address:

Complete degradation of high concentration polyvinyl alcohol (PVA) is challenging. In this article, a two-stage process of NaClO pre-oxidation and columnar activated carbon (loaded with metal active components) catalytic oxidation was used to treat high concentration PVA wastewater. The degree of polymerization of PVA is 2400 and the water concentration is 15 wt %. Read More

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Critical assessment of an equilibrium-based method to study the binding of waterborne organic contaminants to natural dissolved organic matter (DOM).

Chemosphere 2021 Jul 12;285:131524. Epub 2021 Jul 12.

Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, 0349, Oslo, Norway; RECETOX, Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic.

Dissolved organic matter (DOM) can play a major role in determining availability of pollutants to aquatic biota. Equilibrium dialysis is the most commonly used method to assess the interaction between DOM and organic contaminants. However, results obtained through this method can be affected by confounding factors linked to the diffusion of DOM through the membrane or the interaction of DOM and/or the compounds with the membrane itself. Read More

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Adsorption performance and kinetic study of hierarchical porous Fe-based MOFs for toluene removal.

Sci Total Environ 2021 Jun 22;793:148622. Epub 2021 Jun 22.

Faculty of Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, UK.

In light of the promising merits of large surface area, uniform pore size, and tunable functional groups, metal-organic frameworks (MOFs) have great potential to be utilized for adsorbing volatile organic compounds (VOCs). In this study, three Fe-based MOFs, MIL-100(Fe), MIL-101(Fe), and MIL-53(Fe), were synthesized systematically and used to adsorb a typical VOC, toluene. Static adsorption, dynamic breakthrough curves, and adsorption kinetics were conducted to assess the adsorption performance. Read More

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In Situ Oxygen Generation Enhances the SCAP Survival in Hydrogel Constructs.

J Dent Res 2021 Jul 30:220345211027155. Epub 2021 Jul 30.

Restorative Dental Science, Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong, China.

Prolonged and severe hypoxia is the main cause of death of transplanted cells prior to the establishment of functional circulation. In situ generation of oxygen by oxygen-producing scaffolds-a unique solution that could produce and deliver oxygen to the adjacent cells independently of blood perfusion-has attracted considerable attention to enhance the survivability of the transplanted cells. However, the application of oxygen-generating scaffolds for facilitating cell survival in pulp-like tissue regeneration is yet to be explored. Read More

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Aerogelation of Polymer-Coated Photoluminescent, Plasmonic, and Magnetic Nanoparticles for Biosensing Applications.

ACS Appl Nano Mater 2021 Jul 8;4(7):6678-6688. Epub 2021 Jul 8.

Institute of Physical Chemistry and Electrochemistry, Leibniz Universität Hannover, Callinstr. 3a, Hanover 30167, Germany.

Macroscopic materials with nanoscopic properties have recently been synthesized by self-assembling defined nanoparticles to form self-supported networks, so-called aerogels. Motivated by the promising properties of this class of materials, the search for versatile routes toward the controlled assembly of presynthesized nanoparticles into such ultralight macroscopic materials has become a great interest. Overcoating procedures of colloidal nanoparticles with polymers offer versatile means to produce aerogels from nanoparticles, regardless of their size, shape, or properties while retaining their original characteristics. Read More

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Selective and easy detection of microcystin-LR in freshwater using a bioactivated sensor based on multiwalled carbon nanotubes on filter paper.

Biosens Bioelectron 2021 Jul 24;192:113529. Epub 2021 Jul 24.

Department of Chemistry, Pukyong National University, Namgu, 48513, Republic of Korea. Electronic address:

Microcystin-LR (MC-LR) is a cyanobacterial toxin produced as a result of eutrophication in polluted water in warm weather conditions. The MC-LR could cause health problems in mammal organs such as the liver, heart, and muscle. Therefore, the World Health Organization (WHO) has stipulated a limit of <1. Read More

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Fabrication of highly permeable and anti-fouling performance of Poly(ether ether sulfone) nanofiltration membranes modified with zinc oxide nanoparticles.

Chemosphere 2021 Jul 21;286(Pt 1):131616. Epub 2021 Jul 21.

Integrated Bioprocessing Laboratory, School of Bioengineering, SRM Institute of Science and Technology (SRM IST), Kattankulathur, Tamil Nadu, 603 203, India. Electronic address:

Membrane fouling is one of the challenging bottleneck problems in waste water treatment by membrane process. The present study constructed a nanofiltration membrane based on the zinc oxide nanoparticle (n-ZnO) integrated Poly(ether ether sulfone) (PEES) membranes. The developed membranes were characterized by X-ray diffraction (XRD), attenuated total reflectance - fourier transform infrared spectroscopy (AT-FTIR), atomic force microscopy (AFM) and scanning electron microscope (SEM) coupled with energy dispersive X-ray (EDX) analysis. Read More

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Microstructure characteristics of aggregates and Cd immobilization performance under a 3-year sepiolite amendment: A field study.

Sci Total Environ 2021 Jul 24;798:149269. Epub 2021 Jul 24.

Key Laboratory of Original Agro-Environmental Pollution Prevention and Control, Ministry of Agriculture and Rural Affairs (MARA), Tianjin 300191, China; Tianjin Key Laboratory of Agro-Environment and Agro-Product Safety, Agro-Environmental Protection Institute, MARA, Tianjin 300191, China. Electronic address:

Sepiolite is an efficient mineral for the immobilization of Cd in contaminated soils. Here, we conducted a 3-year field experiment to investigate the effect of sepiolite on soil aggregation and porosity, Cd availability, and organic carbon content in the bulk and aggregate soils and Cd accumulation by leafy vegetables. The sepiolite-treated soils showed a 15. Read More

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A new purification technique to obtain specific size distribution of giant lipid vesicles using dual filtration.

PLoS One 2021 29;16(7):e0254930. Epub 2021 Jul 29.

Department of Mathematics and Physics, North South University, Dhaka, Bangladesh.

A new purification technique is developed for obtaining distribution of giant unilamellar vesicles (GUVs) within a specific range of sizes using dual filtration. The GUVs were prepared using well known natural swelling method. For filtration, different combinations of polycarbonate membranes were implemented in filter holders. Read More

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Features of Bioaccumulation and Toxic Effects of Copper (II) Oxide Nanoparticles Under Repeated Oral Exposure in Rats.

Pharm Nanotechnol 2021 Jul 28. Epub 2021 Jul 28.

Federal Scientific Center for Medical and Preventive Health Risk Management Technologies Perm, Russian Federation.

Background: Currently, the range of copper (II) oxide nanoparticles' (CuO NPs) applications is expanding and the global production of CuO NPs is increasing. In this regard, the risk of exposure of the population to this nanomaterial increases.

Objective: The aim of the study is to investigate the patterns of bioaccumulation and toxic effects of CuO NPs after multiple oral exposures. Read More

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Potential biodegradable face mask to counter environmental impact of Covid-19.

Clean Eng Technol 2021 Oct 22;4:100218. Epub 2021 Jul 22.

Department of Chemistry, Government Degree College Mendhar, Jammu and Kashmir, 185211, India.

On the eve of the outbreak of the COVID-19 pandemic, there is a tremendous increase in the production of facemasks across the world. The primary raw materials for the manufacturing of the facemasks are non-biodegradable synthetic polymers derived from petrochemicals. Disposal of these synthetic facemasks increases waste-load in the environment causing severe ecological issues for flora and fauna. Read More

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October 2021

Biomaterials with structural hierarchy and controlled 3D nanotopography guide endogenous bone regeneration.

Sci Adv 2021 Jul 28;7(31). Epub 2021 Jul 28.

Department of Surgery-Transplant and Mary & Dick Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, NE 68198, USA.

Biomaterials without exogenous cells or therapeutic agents often fail to achieve rapid endogenous bone regeneration with high quality. Here, we reported a class of three-dimensional (3D) nanofiber scaffolds with hierarchical structure and controlled alignment for effective endogenous cranial bone regeneration. 3D scaffolds consisting of radially aligned nanofibers guided and promoted the migration of bone marrow stem cells from the surrounding region to the center in vitro. Read More

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Multipulsed Millisecond Ozone Gasification for Predictable Tuning of Nucleation and Nucleation-Decoupled Nanopore Expansion in Graphene for Carbon Capture.

ACS Nano 2021 Jul 28. Epub 2021 Jul 28.

Laboratory of Advanced Separations (LAS), École Polytechnique Fédérale de Lausanne (EPFL), Rue de l'Industrie 17, CH-1951 Sion, Switzerland.

Predictable and tunable etching of angstrom-scale nanopores in single-layer graphene (SLG) can allow one to realize high-performance gas separation even from similar-sized molecules. We advance toward this goal by developing two etching regimes for SLG where the incorporation of angstrom-scale vacancy defects can be controlled. We screen several exposure profiles for the etchant, controlled by a multipulse millisecond treatment, using a mathematical model predicting the nucleation and pore expansion rates. Read More

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Depth sequence distribution of water extractable colloidal phosphorus and its phosphorus speciation in intensively managed agricultural soils.

Chemosphere 2021 Jul 23;286(Pt 1):131665. Epub 2021 Jul 23.

Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, 61801, USA. Electronic address:

Legacy phosphorus (P) has accelerated the subsurface transport of colloidal P (CP) in intensively managed agricultural soils in the Midwestern U.S. Because of its high P sorption capacity and mobility, understanding the depth sequence distribution of mobile CP and its speciation in the soil profile is critical in assessing total P (TP) loss to protect the water quality of adjacent water bodies. Read More

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The rheological, mechanical and heavy metal leaching properties of cemented paste backfill under the influence of anionic polyacrylamide.

Chemosphere 2021 Jul 21;286(Pt 1):131630. Epub 2021 Jul 21.

School of Resources and Safety Engineering, Central South University, Changsha, 410083, China. Electronic address:

Anionic polyacrylamide (APAM) has widely been employed in backfill mining to accelerate the sedimentation of fine tailings particles and increase the concentration of tailings slurry. However, APAM inevitably remains in thickened tailings, leading to a nonnegligible influence on the rheological, mechanical, and heavy metal leaching properties of tailings-based cemented paste backfill (CPB). In an effort to solve these issues, the influences of APAM on CPB properties were examined in the present study. Read More

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Preparation and characterization of chitosan/polyvinyl porous alcohol aerogel microspheres with stable physicochemical properties.

Int J Biol Macromol 2021 Jul 24. Epub 2021 Jul 24.

Key Laboratory of Bionic Engineering (Ministry of Education), College of Biological and Agricultural Engineering, Jilin University, Changchun 130022, China. Electronic address:

Chitosan/polyvinyl alcohol (CS/PVA) porous aerogel microspheres with stable physicochemical properties were obtained by gelation and freeze-drying process, and modified by adding different content of polyvinyl alcohol (PVA) into the microspheres. The physicochemical properties of porous aerogel microspheres, including porosity, swelling degree, acid-base resistance and compression performance were compared with chitosan (CS) microspheres. The microspheres were characterized by scanning electronic microscopy, Fourier transform infrared spectra, X-ray diffraction and compression test. Read More

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Designable Assembly of Aluminum Molecular Rings for Sequential Confinement of Iodine Molecules.

Angew Chem Int Ed Engl 2021 Jul 27. Epub 2021 Jul 27.

Chinese Academy of Sciences Fujian Institute of Research on the Structure of Matter, State key laboratory of structural chemistry, 350002, Fuzhou, CHINA.

Although numerous adsorbent materials have been reported for radioactive iodine capture, demands for the development of new absorbents that are economically viable and featured with reliable synthetic protocols still exist. Herein, in this paper, a coordination-driven self-assembly strategy towards adsorbents for sequential confinement of iodine molecules is reported. It should be noticed that these adsorbents are versatile heterometallic frameworks constructed from aluminum molecular rings of varying size, flexible copper ions and conjugated carboxylate ligands. Read More

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A Porous Metal-Organic Framework as an Electrochemical Sensing Platform for Highly Selective Adsorption and Detection of Bisphenols.

Inorg Chem 2021 Jul 27. Epub 2021 Jul 27.

Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education, Faculty of Chemistry, Northeast Normal University, Changchun, Jilin 130024, China.

The design of artificial receptors with a specific recognition function and enhanced selectivity is highly desirable in the electrochemical sensing field, which can be used for detection of environmental pollutants. In this facet, metal-organic frameworks (MOFs) featured adjustable porosities and specific host-guest recognition properties. Especially, the large hydrophobic cavity formed in the porous MOFs may become a potential artificial receptor. Read More

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Influence of alternated drying and wetting on the characteristics of soil preferential flow formation in Honghe Arid Valley.

Ying Yong Sheng Tai Xue Bao 2021 Jul;32(7):2397-2406

Xinping Yi and Dai Autonomous County Water Conservancy Bureau, Yuxi 653400, Yunnan, China.

To clarify the effects of alternation of drying and wetting on the formation of soil preferential flow in arid valley, taking the wasteland in the arid valley of Honghe River as the research object, we analyzed the soil preferential flow characteristics before and after the simulation of drying and wetting alternation based on dyeing tracer method, water breakthrough curve, and image processing technology. The results showed that, under the simulated alternation of drying and wetting, the matrix flow occurred in the 0-10 cm soil layer, the dyeing depth reached 35 cm, the horizontal width of the preferred path was only 3-10 cm, and the dyeing area curve fluctuated little. Simulated alternation of drying and wetting led to significant increases in the steady effluent, macropores number, and macroporosity. Read More

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Kidney damage from nonsteroidal anti-inflammatory drugs-Myth or truth? Review of selected literature.

Pharmacol Res Perspect 2021 Aug;9(4):e00817

Department of Pharmacokinetics and Monitored Therapy, Pomeranian Medical University, Szczecin, Poland.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely available drugs with anti-inflammatory and analgesic properties. Their mechanism of action is associated with the enzymes of the arachidonic acid cycle (cyclooxygenases: COX-1 and COX-2). The cyclooxygenase pathway results in the formation of prostanoids (prostaglandins [PGs], prostacyclins, and thromboxanes). Read More

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[ biological safety study of porous zinc oxide/hydroxyapatite composite materials].

Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi 2021 Jul;35(7):847-854

Department of Orthopedics, the First People's Hospital of Yunnan Province, Kunming Yunnan, 650032, P.R.China.

Objective: To evaluate the biological safety of porous zinc oxide (ZnO)/hydroxyapatite (HA) composite materials.

Methods: The porous ZnO/HA composite materials and porous HA materials were prepared by the spark plasma sintering technology. First, the materials were characterized, including scanning electron microscopy to observe the material structure, degradation experiments to detect the degradation rate of the materials, and inductively coupled plasma emission spectrometer to detect the concentration of Zn dissolved out of the composite material degradation. Read More

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Water-rock interaction and the concentrations of major, trace, and rare earth elements in hydrocarbon-associated produced waters of the United States.

Environ Sci Process Impacts 2021 Jul 26. Epub 2021 Jul 26.

U.S. Geological Survey, Geology, Energy & Minerals Science Center, Reston, Virginia, USA.

Studies of co-produced waters from hydrocarbon extraction across multiple energy-producing basins have generally focused on major ions or a few select tracers, and studies that examine trace elements and involve laboratory experiments have generally been basin specific. Here, new perspective is sought through a broad analysis of concentration data for 26 elements from three hydrocarbon well types using the U.S. Read More

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Confined Crystallization and Melting Behaviors of 3-Pentadecylphenol in Anodic Alumina Oxide Nanopores.

ACS Omega 2021 Jul 8;6(28):18235-18247. Epub 2021 Jul 8.

State Key Laboratory of High-Efficiency Coal Utilization and Green Chemical Engineering, Ningxia University, 489 Helanshan West Road, Yinchuan 750021, China.

To explore the effects of end groups on the confined crystallization of an alkyl chain, 3-pentadecylphenol (PDP) was infiltrated into the anodic aluminum oxide template (AAO) to investigate the melting and crystallization behaviors of PDP in a nanoconfined environment. Wide-angle X-ray diffraction (WAXD) found that the solid-solid phase transition of PDP occurred under confined conditions, and the absence of the (00L) reflections indicated that the stacking of the end groups of the alkyl chain layered structure was seriously disturbed. Thermal analysis (TG) showed that the thermal stability of the confined samples decreased due to the confinement effect, and the introduction of end groups made the confinement effect more obvious. Read More

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Chitosan/Gelatin/PVA Scaffolds for Beta Pancreatic Cell Culture.

Polymers (Basel) 2021 Jul 20;13(14). Epub 2021 Jul 20.

CINTROP, Department of Basic Sciences, Medicine School, Health Faculty, Universidad Industrial de Santander, Cra 27 calle 9, Bucaramanga 680002, Colombia.

Chitosan scaffolds based on blending polymers are a common strategy used in tissue engineering. The objective of this study was evaluation the properties of scaffolds based on a ternary blend of chitosan (Chi), gelatin (Ge), and polyvinyl alcohol (PVA) (Chi/Ge/PVA), which were prepared by cycles of freeze-thawing and freeze-drying. It then was used for three-dimensional BRIN-BD11 beta-cells culturing. Read More

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Thermophysical Properties of Larch Bark Composite Panels.

Polymers (Basel) 2021 Jul 12;13(14). Epub 2021 Jul 12.

Faculty of Wood Sciences and Technology, Technical University in Zvolen, 96001 Zvolen, Slovakia.

The effects of using 100% larch bark ( Mill) as a raw material for composite boards on the thermophysical properties of this innovative material were investigated in this study. Panels made of larch bark with 4-11 mm and 10-30 mm particle size, with ground bark oriented parallel and perpendicular to the panel's plane at densities varying from 350 to 700 kg/m and bonded with urea-formaldehyde adhesive were analyzed for thermal conductivity, thermal resistivity and specific heat capacity. It was determined that there was a highly significant influence of bulk density on the thermal conductivity of all the panels. Read More

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Design of Olmesartan Medoxomil-Loaded Nanosponges for Hypertension and Lung Cancer Treatments.

Polymers (Basel) 2021 Jul 11;13(14). Epub 2021 Jul 11.

Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Matériaux, University Pau & Pays Adour, 64000 Pau, France.

Olmesartan medoxomil (OLM) is one of the prominent antihypertensive drug that suffers from low aqueous solubility and dissolution rate leading to its low bioavailability. To improve the oral bioavailability of OLM, a delivery system based on ethylcellulose (EC, a biobased polymer) nanosponges (NSs) was developed and evaluated for cytotoxicity against the A549 lung cell lines and antihypertensive potential in a rat model. Four OLM-loaded NSs (ONS1-ONS4) were prepared and fully evaluated in terms of physicochemical properties. Read More

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Evaluation of 3D-Printing Scaffold Fabrication on Biosynthetic Medium-Chain-Length Polyhydroxyalkanoate Terpolyester as Biomaterial-Ink.

Polymers (Basel) 2021 Jul 6;13(14). Epub 2021 Jul 6.

College of Biomedical Engineering, Rangsit University, 52/347 Phahonyothin Road, Pathum Thani 12000, Thailand.

Currently, the selection of materials for tissue engineering scaffolds is still limited because some tissues require flexible and compatible materials with human cells. Medium-chain-length polyhydroxyalkanoate (MCL-PHA) synthesized in microorganisms is an interesting polymer for use in this area and has elastomeric properties compatible with the human body. MCL-PHAs are elastomers with biodegradability and cellular compatibility, making them an attractive material for fabricating soft tissue that requires high elasticity. Read More

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