Records |
Author |
Abisha, M.; Priya, R.K.; Arunachalam, K.P.; Avudaiappan, S.; Flores, E.I.S.; Parra, P.F. |
Title |
Biodegradable Green Composites: Effects of Potassium Permanganate (KMnO4) Treatment on Thermal, Mechanical, and Morphological Behavior of Butea Parviflora (BP) Fibers |
Type |
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Year |
2023 |
Publication |
Polymers |
Abbreviated Journal |
Polymers |
Volume |
15 |
Issue |
9 |
Pages |
2197 |
Keywords |
cellulosic fiber; crystallinity; sustainability; green composites |
Abstract |
This study emphasizes the importance of utilizing biodegradable material Butea parviflora (BP) fiber for sustainable solutions. BP fiber offers numerous ecological benefits, such as being lightweight, biodegradable, and affordable to recycle. The study examines the effects of potassium permanganate (KMnO4) treatment on BP fiber and analyzes its physical and chemical behavior using various methods, including X-ray Diffraction (XRD) analysis, tensile testing, thermogravimetric analysis, thermal conductivity, Scanning Electron Microscopy (SEM), and Fourier Transform Infrared spectroscopic (FTIR) analysis. The results demonstrate that BP fiber possesses low density (1.40 g/cc) and high cellulose content (59.4%), which fosters compatibility between the matrix and resin. XRD analysis indicates a high crystallinity index (83.47%) and crystallite size (6.4 nm), showcasing exceptional crystalline behavior. Treated fibers exhibit improved tensile strength (198 MPa) and Young's modulus (4.40 GPa) compared to untreated fibers (tensile strength-92 MPa, tensile modulus-2.16 GPa). The Tg-DTA thermograms reveal the fiber's thermal resistance up to 240 degrees C with a kinetic activation energy between 62.80-63.46 KJ/mol. Additionally, the lowered thermal conductivity (K) from Lee's disc experiment suggests that BP fiber could be used in insulation applications. SEM photographic results display effective surface roughness for composite making, and FTIR studies reveal vibrational variations of cellulosic functional groups, which correlates with increased cellulosic behavior. Overall, the study affirms the potential of BP fiber as a reinforcing material for composite-making while emphasizing the importance of utilizing biodegradable materials for sustainability. |
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2073-4360 |
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Notes |
WOS:000987521600001 |
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Call Number |
UAI @ alexi.delcanto @ |
Serial |
1830 |
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Author |
Cabrera, F.; Torres, A.; Campos, J.L.; Jeison, D. |
Title |
Effect of Operational Conditions on the Behaviour and Associated Costs of Mixed Microbial Cultures for PHA Production |
Type |
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Year |
2019 |
Publication |
Polymers |
Abbreviated Journal |
Polymers |
Volume |
11 |
Issue |
2 |
Pages |
14 pp |
Keywords |
PHA; mixed microbial cultures; bioplastics; feast-famine; cost |
Abstract |
Massive production and disposal of petrochemical derived plastics represent relevant environmental problems. Polyhydroxyalkanoates (PHA) are a renewable alternative that can even be produced from wastes. The production of PHA from acetate using mixed microbial cultures was studied. The effect of two key operational conditions was evaluated, i.e., substrate concentration and cycle length. The effects of these factors on several responses were studied using a surface response methodology. Several reactors were operated under selected conditions for at least 10 solids retention times to ensure stable operation. Results show that conditions providing higher PHA content involve lower biomass productivities. This has a great impact on biomass production costs. Results suggest then that PHA content alone may not be a reasonable criterion for determining optimal conditions for PHB production. If production costs need to be reduced, conditions that provide a lower PHA content in the selection reactor, but a higher biomass productivity may be of interest. |
Address |
[Cabrera, Francisco; Torres, Alvaro] Univ La Frontera, Dept Chem Engn, Ave Francisco Salazar 01145, Temuco 4780000, Chile, Email: f.cabrera01@ufromail.cl; |
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Mdpi |
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English |
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2073-4360 |
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Notes |
WOS:000460296000005 |
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Call Number |
UAI @ eduardo.moreno @ |
Serial |
986 |
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Author |
Caceres, C.; Moczko, E.; Basozabal, I.; Guerreiro, A.; Piletsky, S. |
Title |
Molecularly Imprinted Nanoparticles (NanoMIPs) Selective for Proteins: Optimization of a Protocol for Solid-Phase Synthesis Using Automatic Chemical Reactor |
Type |
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Year |
2021 |
Publication |
Polymers |
Abbreviated Journal |
Polymers |
Volume |
13 |
Issue |
3 |
Pages |
314 |
Keywords |
molecularly imprinted nanoparticles; solid-phase synthesis; automatic chemical reactor; protein imprinting |
Abstract |
Molecularly imprinted polymer nanoparticles (nanoMIPs) are receiving broad interest as robust and highly selective synthetic receptors for a variety of molecules. Due to their stability, inexpensive synthesis and easy implementation, they are considered a promising alternative to antibodies in sensors, diagnostics and separation applications. The most challenging targets for the production of synthetic receptors are proteins due to their fragile nature and the multitude of possible binding sites in their structure. Herein, we describe the modification and optimization of the protocol for synthesis of nanoMIPs with specificity for proteins using the prototype of an automated solid-phase synthesizer. Using an automated system gives an advantage for the simple, fast and fully controlled, reproducible production of nanoMIPs. The molecular imprinting in the reactor is performed using a template covalently immobilized on a solid support, in mild conditions suitable for preserving protein native structure. The validation of the protocol was made by assessing the ability to regenerate a solid-phase, and by measuring affinity and specificity of nanoparticles. As a model protein, we have chosen trypsin since its enzymatic activity can be easily monitored by using a commercial colorimetric assay. Different protocols were tested for their ability to improve the yield of high affinity nanoparticles in the final elution. |
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2073-4360 |
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WOS:000615458100001 |
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Call Number |
UAI @ alexi.delcanto @ |
Serial |
1338 |
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Author |
Caceres, C.; Morgado, M.D.G.; Bozo, F.C.; Piletsky, S.; Moczko, E. |
Title |
Rapid Selective Detection and Quantification of beta-Blockers Used in Doping Based on Molecularly Imprinted Nanoparticles (NanoMIPs) |
Type |
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Year |
2022 |
Publication |
Polymers |
Abbreviated Journal |
Polymers |
Volume |
14 |
Issue |
24 |
Pages |
5420 |
Keywords |
doping in sports; performance enhancing drugs (PEDs); beta-blockers; atenolol; labetalol; molecularly imprinting nanoparticles (nanoMIPs); enzyme-linked immunosorbent assay (ELISA); “pseudo” enzyme-linked immunosorbent assay (pseudo-ELISA); dynamic analysis light scattering (DLS); transmission electron microscope (TEM) |
Abstract |
Human performance enhancing drugs (PEDs), frequently used in sport competitions, are strictly prohibited by the World Anti-Doping Agency (WADA). Biological samples collected from ath-letes and regular patients are continuously tested regarding the identification and/or quantification of the banned substances. Current work is focused on the application of a new analytical method, molecularly imprinted nanoparticles (nanoMIPs), to detect and determine concentrations of certain prohibited drugs, such as B-blockers, in water and human urine samples. These medications are used in the treatment of cardiovascular conditions, negative effects of adrenaline (helping to relief stress), and hypertension (slowing down the pulse and softening the arteries). They can also significantly increase muscle relaxation and improve heart efficiency. The new method of the detection and quantification of B-blockers is based on synthesis, characterization, and implementation of nanoMIPs (so-called plastic antibodies). It offers numerous advantages over the traditional methods, including high binding capacity, affinity, and selectivity for target molecules. Additionally, the whole process is less complicated, cheaper, and better controlled. The size and shape of the nanoMIPs is evaluated by dynamic light scattering (DLS) and transmission electron microscope (TEM). The affinity and selectivity of the nanoparticles are investigated by competitive pseudo enzyme-linked immunosorbent assay (pseudo-ELISA) similar to common immunoassays employing natural antibodies. To provide reliable results towards either doping detection or therapeutic monitoring using the minimal invasive method, the qualitative and quantitative analysis of these drugs is performed in water and human urine samples. It is demonstrated that the assay can detect B-blockers in water within the linear range 1 nmolmiddotL(-1)-1 mmolmiddotL(-1) for atenolol with the detection limit 50.6 ng mL(-1), and the linear range 1 mmolmiddotL(-1)-10 mmolmiddotL(-1) for labetalol with the detection limit of 90.5 ngmiddotmL(-1). In human urine samples, the linear range is recorded in the concentration range 0.1 mmolmiddotL(-1)-10 nmolmiddotL(-1) for atenolol and 1 mmolmiddotL(-1)-10 nmolmiddotL(-1) for labetalol with a detection limit of 61.0 ngmiddotmL(-1)for atenolol and 99.4 ngmiddotmL(-1) for labetalol. |
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2073-4360 |
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Notes |
WOS:000904441600001 |
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UAI @ alexi.delcanto @ |
Serial |
1710 |
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Author |
Contreras-Raggio, J.I.; Arancibia, C.T.; Millan, C.; Ploeg, H.L.; Aiyangar, A.; Vivanco, J.F. |
Title |
Height-to-Diameter Ratio and Porosity Strongly Influence Bulk Compressive Mechanical Properties of 3D-Printed Polymer Scaffolds |
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Year |
2022 |
Publication |
Polymers |
Abbreviated Journal |
Polymers |
Volume |
14 |
Issue |
22 |
Pages |
5017 |
Keywords |
polymer scaffolds; 3D printing; height; diameter ratio; porosity; pore size; mechanical properties |
Abstract |
Although the architectural design parameters of 3D-printed polymer-based scaffolds-porosity, height-to-diameter (H/D) ratio and pore size-are significant determinants of their mechanical integrity, their impact has not been explicitly discussed when reporting bulk mechanical properties. Controlled architectures were designed by systematically varying porosity (30-75%, H/D ratio (0.5-2.0) and pore size (0.25-1.0 mm) and fabricated using fused filament fabrication technique. The influence of the three parameters on compressive mechanical properties-apparent elastic modulus E-app, bulk yield stress sigma(y) and yield strain epsilon(y)-were investigated through a multiple linear regression analysis. H/D ratio and porosity exhibited strong influence on the mechanical behavior, resulting in variations in mean E-app of 60% and 95%, respectively. sigma(y) was comparatively less sensitive to H/D ratio over the range investigated in this study, with 15% variation in mean values. In contrast, porosity resulted in almost 100% variation in mean sigma(y) values. Pore size was not a significant factor for mechanical behavior, although it is a critical factor in the biological behavior of the scaffolds. Quantifying the influence of porosity, H/D ratio and pore size on bench-top tested bulk mechanical properties can help optimize the development of bone scaffolds from a biomechanical perspective. |
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2073-4360 |
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Notes |
WOS:000887647600001 |
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Call Number |
UAI @ alexi.delcanto @ |
Serial |
1655 |
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Author |
Valle, H.; Palao-Suay, R.; Aguilar, M.R.; Lerma, T.A.; Palencia, M.; Mangalaraja, R.V.; Guzmán, L.; Sotelo, D.P.; Becerra, J. |
Title |
Nanocarrier of α-Tocopheryl Succinate Based on a Copolymer Derivative of (4,7-dichloroquinolin-2-yl)methanol and Its Cytotoxicity against a Breast Cancer Cell Line |
Type |
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Year |
2023 |
Publication |
Polymers |
Abbreviated Journal |
Polymers |
Volume |
15 |
Issue |
22 |
Pages |
4342 |
Keywords |
biomedical applications; copolymers; nanoparticles; radical polymerization; self-assembly; anticancer |
Abstract |
In order to improve the water solubility and, therefore, bioavailability and therapeutic activity of anticancer hydrophobic drug alpha-tocopherol succinate (alpha-TOS), in this work, copolymers were synthesized via free radicals from QMES (1-[4,7-dichloroquinolin-2-ylmethyl]-4-methacryloyloxyethyl succinate) and VP (N-vinyl-2-pirrolidone) using different molar ratios, and were used to nanoencapsulate and deliver alpha-TOS into cancer cells MCF-7. QMES monomer was chosen because the QMES pendant group in the polymer tends to hydrolyze to form free 4,7-dichloro-2-quinolinemethanol (QOH), which also, like alpha-TOS, exhibit anti-proliferative effects on cancerous cells. From the QMES-VP 30:70 (QMES-30) and 40:60 (QMES-40) copolymers obtained, it was possible to prepare aqueous suspensions of empty nanoparticles (NPs) loaded with alpha-TOS by nanoprecipitation. The diameter and encapsulation efficiency (%EE) of the QMES-30 NPs loaded with alpha-TOS were 128.6 nm and 52%; while for the QMES-40 NPs loaded with alpha-TOS, they were 148.8 nm and 65%. The results of the AlamarBlue assay at 72 h of treatment show that empty QMES-30 NPs (without alpha-TOS) produced a marked cytotoxic effect on MCF-7 breast cancer cells, corresponding to an IC50 value of 0.043 mg mL-1, and importantly, they did not exhibit cytotoxicity against healthy HUVEC cells. Furthermore, NP-QMES-40 loaded with alpha-TOS were cytotoxic with an IC50 value of 0.076 mg mL-1, demonstrating a progressive release of alpha-TOS; however, the latter nanoparticles were also cytotoxic to healthy cells in the range of the assayed concentrations. These results contribute to the search for a new polymeric nanocarrier of QOH, alpha-TOS or other hydrophobic drugs for the treatment of cancer or others diseases treatable with these drugs. |
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2073-4360 |
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WOS:001113769100001 |
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UAI @ alexi.delcanto @ |
Serial |
1928 |
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