How Poloxamer Addition in Hyaluronic-Acid-Decorated Biodegradable Microparticles Affects Polymer Degradation and Protein Release Kinetics

Polymeric microparticles (MPs) designed for the intravitreal administration of therapeutic proteins result in a prolonged half-life in the vitreous and can delay or discourage the onset of adverse effects inevitably related to this route of administration. Hence, here we designed MPs composed of a polymeric blend based on poly(lactic-co-glycolic) acid and poloxamers, externally decorated with hyaluronic acid. The MPs are intended for intravitreal administration of bovine serum albumin. In detail, a systematic formulative study aiming to shed light on the complex relationship between protein release rate and MP degradation rate was carried out by means of calorimetric and gel permeation chromatography analyses. We found out that poloxamer addition caused a compact MP matrix, which led to a slight modification of the degradation kinetics and a reduction in the initial BSA initial release, which is of the utmost importance to ensure a relatively regular BSA release. It must also be underlined that for acid-labile molecules such as proteins, the poloxamer’s presence induced complex and hardly predictable effects on MP degradation/protein release, due to the dynamic balance between the time-evolving hydrophilicity of MPs and the influence of poloxamers themselves on the PLGA degradation rate.

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In situ degradability of dry matter and fibrous fraction of sorghum silage

Acta Scientiarum Animal Sciences ◽

10.4025/actascianimsci.v38i2.29576 ◽

2016 ◽

Vol 38 (2) ◽

pp. 171 ◽

Cited By ~ 1

Author(s):

Renê Ferreira Costa ◽

Daniel Ananias de Assis Pires ◽

Marielly Maria Almeida Moura ◽

José Avelino Santos Rodrigues ◽

Vicente Ribeiro Rocha Júnior ◽

...

Keyword(s):

Experimental Design ◽

Dry Matter ◽

Degradation Rate ◽

Degradation Kinetics ◽

Grain Sorghum ◽

Dual Purpose ◽

Ruminal Degradability ◽

Sorghum Silage ◽

Kinetics Of

This study aimed to evaluate in situ degradability and degradation kinetics of DM, NDF and ADF of silage, with or without tannin in the grains. Two isogenic lines of grain sorghum (CMS-XS 114 with tannin and CMS-XS 165 without tannin) and two sorghum hybrids (BR-700 dual purpose with tannin and BR-601 forage without tannin) were ensiled; dried and ground silage samples were placed in nylon bags and introduced through the fistulas. After incubation for 6, 12, 24, 48, 72 and 96 hours, bags were taken for subsequent analysis of fibrous fractions. The experimental design was completely randomized with 4 replicates and 4 treatments and means compared by Tukey’s test at 5% probability. As for the DM degradation rate, silage of CMSXS165without tannin was superior. Silages of genotypes BR700 and CMSXS 114 with tannin showed the highest values of indigestible ADF (59.54 and 43.09%). Regarding the NDF, the potential degradation of silage of CMSXS165 line without tannin was superior. Tannin can reduce ruminal degradability of the dry matter and fibrous fractions.

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Effect of PEEK degradation on commingled fabrics consolidation

10.25518/esaform21.1985 ◽

2021 ◽

Author(s):

Lisa Feuillerat ◽

Olivier De Almeida ◽

Jean-Charles Fontanier ◽

Fabrice Schmidt

Keyword(s):

Melt Spinning ◽

Molar Mass ◽

Degradation Kinetics ◽

Gel Permeation Chromatography ◽

Raw Material ◽

High Porosity ◽

Absorption Bands ◽

Mass Distributions ◽

Key Factor ◽

Lower Molar

The effects of PEEK degradation on consolidation of commingled semi-finished products have been investigated. Two commingled semi-finished products provided by two different suppliers have been studied and compared to a powdered fabric based on the same PEEK grade. Both were manufactured from aligned AS4 carbon and PEEK yarns but the first product referred as the NCF1 has a lower commingling level than the second one identified as the NCF2. Contrary to what could be expected, under the same processing conditions, consolidation of the NCF1 and the NCF2 systematically results in a high porosity content, above 10%. Fourier Transform Infrared spectrophotometry (FTIR) in ATR mode and Gel Permeation Chromatography (GPC) have shown small molecular structure modifications of PEEK yarns compared to the raw material, such as a shift of molar mass distributions towards lower molar mass and the appearance of C-H absorption bands attributed to non-aromatic alkanes. These modifications have been attributed to sizing of PEEK filament. Calorimetric (DSC) and rheological analyses have demonstrated that the presence of sizing in the semi-finished products have huge consequences on the degradation kinetics. The crystallization temperature decreases and the viscosity increases significantly. This acceleration of the degradation kinetics is the reason of the poor consolidation behavior during composite manufacturing. The conditions of melt spinning extrusion under which the neat PEEK is transformed into filament are therefore a key factor of PEEK degradation.

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Degradation of Remazol Black dye from Aqueous Solution by Heterogeneous NH3(MoO3)3/H2O2 System

International Research Journal of Pure and Applied Chemistry ◽

10.9734/irjpac/2021/v22i730421 ◽

2021 ◽

pp. 67-78

Author(s):

Kouakou Yao Urbain ◽

Kambiré Ollo ◽

Gnonsoro Urbain Paul ◽

Eroi N’goran Sévérin ◽

Trokourey Albert

Keyword(s):

Hydrogen Peroxide ◽

Molybdenum Oxide ◽

Degradation Rate ◽

Dye Degradation ◽

Degradation Kinetics ◽

Sol Gel ◽

Gel Method ◽

Sol Gel Method ◽

Molybdenum Nanoparticles ◽

Remazol Black

Aims: The pollution of the environment by organic dyes in water is a matter of great concern. Wastewater containing dyes is difficult to treat by conventional wastewater treatment methods such as coagulation, ozonation, biological treatment, etc. This is why the implementation of an effective method by not generating pollutants secondary is necessary. The objective of this work is to study the degradation of remazol black, an azo dye, by the coupling of hydrogen peroxide - molybdenum oxide nanoparticle. The nanoparticles were synthesized by the aqueous sol-gel method using a reflux assembly. Study Design: Random design. Methodology: The nanoparticles were synthesized by the aqueous sol-gel method using a reflux assembly and then characterized by X-ray diffraction and using software origin to determine the particles size by Scherrer's formula. The influence of hydrogen peroxide, molybdenum oxide and hydrogen peroxide / molybdenum oxide coupling, and the degradation kinetics of remazol black were studied. We also studied the influence of the pH of the solution, the mass of molybdenum nanoparticles and the concentration of remazol black on the dye degradation process. Results: The results showed that the synthesized oxide is ammonium molybdenum trioxide NH3(MoO3)3) with a hexagonal structure and size 22.79 nm. The study of the catalytic effect revealed a degradation rate of 17%, 0.83% and 42% respectively for H2O2, NH3(MoO3)3 and the coupling NH3(MoO3)3/H2O2. The study also showed that the degradation of remazol black by the couple NH3(MoO3)3 /H2O2 is better at pH = 4 and for a mass of nanoparticles of 400 mg. This degradation kinetics are pseudo 1st order. In addition, the degradation rate decreases when the concentration of remazol black increases. The efficiency of the coupling (NH3(MoO3)3 / H2O2 showed at ambient temperature, that it was possible to remove about 60% of the initial color of remazol black from the water in a batch reaction. Conclusion: The reflux method makes it possible to synthesize molybdenum nanoparticles. The molybdenum oxide hetero-Fenton process is effective in removing remazol black dye from water.

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Synthesis and characterization of novel methacrylate copolymers having pendant piperonyl group: monomer reactivity ratio, thermal degradation kinetics, and biological activity

Polymers and Polymer Composites ◽

10.1177/09673911211053978 ◽

2021 ◽

Vol 29 (9_suppl) ◽

pp. S1432-S1445

Author(s):

Ibrahim Erol ◽

Bayram Gencer ◽

Zeki Gurler

Keyword(s):

Biological Activity ◽

Degradation Kinetics ◽

Gel Permeation Chromatography ◽

Reactivity Ratio ◽

Thermal Degradation Kinetics ◽

Scanning Calorimetry ◽

Molecular Weights ◽

Monomer Reactivity Ratio ◽

Bacteria And Fungi ◽

Photo Stability

In this study, 2-{[(2H-1,3-benzodioxol-5-yl)methyl]amino}-2-oxoethyl 2-methylprop-2-enoate (BMAOME) monomer was synthesized, and copolymers were prepared with glycidyl methacrylate (GMA). Structural characterizations of the compounds were performed using FTIR, 1H-, and 13C-NMR techniques. Monomer reactivity ratio values were calculated by Finemann–Ross (FR) and Kelen–Tudos (KT) methods. The Tg value of the polymers was determined by differential scanning calorimetry (DSC) and their thermal stability was determined by thermogravimetric analysis (TGA). The molecular weights (w and n) and polydispersity index of the polymers were determined by gel permeation chromatography. The Ea value of thermal decomposition was determined by using the Ozawa and Kissinger methods. The photo-stability of the copolymers was investigated. Furthermore, the photo-stability of the copolymers and the biological activity of polymers against different types of bacteria and fungi were investigated.

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Hyaluronic acid functionalized nanoparticles for simultaneous delivery of curcumin and resveratrol for management of chronic diabetic wounds: Fabrication, characterization, stability and in vitro release kinetics

Journal of Drug Delivery Science and Technology ◽

10.1016/j.jddst.2020.101747 ◽

2020 ◽

Vol 57 ◽

pp. 101747 ◽

Cited By ~ 4

Author(s):

Zahid Hussain ◽

Manisha Pandey ◽

Hira Choudhury ◽

Pang Cheau Ying ◽

Tan Mei Xian ◽

...

Keyword(s):

Hyaluronic Acid ◽

Release Kinetics ◽

In Vitro Release ◽

Functionalized Nanoparticles ◽

Diabetic Wounds ◽

Vitro Release ◽

Simultaneous Delivery

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Applicability of various amphiphilic polymers to the modification of protein release kinetics from biodegradable reservoir-type microspheres

European Journal of Pharmaceutics and Biopharmaceutics ◽

10.1016/s0939-6411(00)00138-7 ◽

2001 ◽

Vol 51 (1) ◽

pp. 45-53 ◽

Cited By ~ 41

Author(s):

Takahiro Morita ◽

Yuji Horikiri ◽

Takehiko Suzuki ◽

Hiroyuki Yoshino

Keyword(s):

Release Kinetics ◽

Amphiphilic Polymers ◽

Protein Release ◽

Reservoir Type

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Photocatalytic Degradation of Monolinuron and Linuron in an Aqueous Suspension of Titanium Dioxide Under Simulated Solar Irradiation

Revue des sciences de l eau ◽

10.7202/015810ar ◽

2007 ◽

Vol 20 (2) ◽

pp. 163-172 ◽

Cited By ~ 3

Author(s):

Razika Zouaghi ◽

Abdennour Zertal ◽

Bernard David ◽

Sylvie Guittonneau

Keyword(s):

Photocatalytic Degradation ◽

Degradation Rate ◽

Ph Value ◽

Degradation Kinetics ◽

Aqueous Suspension ◽

Operating Conditions ◽

Solar Irradiation ◽

Point Of Zero Charge ◽

Degradation Rates ◽

Simulated Solar Irradiation

Abstract The photocatalytic degradation of two phenylurea herbicides, monolinuron (MLN) and linuron (LN), was investigated in an aqueous suspension of TiO2 using simulated solar irradiation. The objective of the study was to compare their photocatalytic reactivity and to assess the influence of various parameters such as initial pesticide concentration, catalyst concentration and photonic flux on the photocatalytic degradation rate of MLN and LN. A comparative study of the photocatalytic degradation kinetics of both herbicides showed that these two compounds have a comparable reactivity with TiO2/simulated sun light. Under the operating conditions of this study, the photocatalytic degradation of MLN and LN followed pseudo first-order decay kinetics. The kobs values indicated an inverse dependence on the initial herbicide concentration and were fitted to the Langmuir-Hinshelwood equation. Photocatalytic degradation rates increased with TiO2 dosage, but overdoses did not necessarily increase the photocatalytic efficiency. The degradation rate of MLN increased with radiant flux until an optimum at 580 W m‑2 was reached and then decreased. Under these conditions, an electron-hole recombination was favored. Finally, the photocatalytic degradation rate depended on pH, where an optimum was found at a pH value close to the pH of the point of zero charge (pH = 6).

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Nitrogen degradation of the limestone-urea mixtures in the rumen of goats

Journal of the Indonesian Tropical Animal Agriculture ◽

10.14710/jitaa.43.3.282-288 ◽

2018 ◽

Vol 43 (3) ◽

pp. 282

Author(s):

M. A. Harahap ◽

L. K. Nuswantara ◽

E. Pangestu ◽

F. Wahyono ◽

J. Achmadi

Keyword(s):

Dietary Supplement ◽

Dry Matter ◽

Degradation Rate ◽

Slow Release ◽

Soluble Fraction ◽

Degradation Kinetics ◽

Central Java ◽

Ruminal Degradation ◽

Kinetics Of ◽

Central Java Province

This experiment was aimed to study the degradation kinetics of limestone-urea mixtures in the goats rumen using the nylon bag technique. Samples of limestone were obtained from two limestone mountains, Pamotan Subdistrict of Central Java Province and Wonosari Subdistrict of Yogyakarta Province. The mixtures were created by combining urea at levels 25, 50, 75and 100%; respectively with two limestones on the basis of their Ca contents: L0U100, LP25U75, LP50U50; LP75U25, LW25U75; LW50U50; and LW75U25. The soluble fraction, potentially degradable fraction, the degradation rate of potentially degradable fraction, and effective degradation of respective dry matter (DM) and nitrogen (N) ruminal degradation kinetics were measured in each mixture. The mixture of LP75U25 had lowest effective and degradation rate of potentially degradable fraction (P<0.05) respectively for DM and N compared with those of other mixtures. In conclusion, the limestone-urea mixture of LP75U25 could be suggested as a dietary supplement of ruminal N slow release.

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Controlled Release of Interleukin-1 Receptor Antagonist from Hyaluronic Acid-Chitosan Microspheres Attenuates Interleukin-1β-Induced Inflammation and Apoptosis in Chondrocytes

BioMed Research International ◽

10.1155/2016/6290957 ◽

2016 ◽

Vol 2016 ◽

pp. 1-12 ◽

Cited By ~ 6

Author(s):

Bo Qiu ◽

Ming Gong ◽

Qi-Ting He ◽

Pang-Hu Zhou

Keyword(s):

Hyaluronic Acid ◽

Controlled Release ◽

Receptor Antagonist ◽

Release Kinetics ◽

Quantitative Polymerase Chain Reaction ◽

Interleukin 1 ◽

B Cell Lymphoma ◽

Chondrocyte Apoptosis ◽

Burst Release ◽

Interleukin 1 Receptor Antagonist

This paper investigates the protective effect of interleukin-1 receptor antagonist (IL-1Ra) released from hyaluronic acid chitosan (HA-CS) microspheres in a controlled manner on IL-1β-induced inflammation and apoptosis in chondrocytes. The IL-1Ra release kinetics was characterized by an initial burst release, which was reduced to a linear release over eight days. Chondrocytes were stimulated with 10 ng/ml IL-1β and subsequently incubated with HA-CS-IL-1Ra microspheres. The cell viability was decreased by IL-1β, which was attenuated by HA-CS-IL-1Ra microspheres as indicated by an MTT assay. ELISA showed that HA-CS-IL-1Ra microspheres inhibited IL-1β-induced inflammation by attenuating increases in NO2- and prostaglandin E2 levels as well as increase in glycosaminoglycan release. A terminal deoxyribonucleotide transferase deoxyuridine triphosphate nick-end labeling assay revealed that the IL-1β-induced chondrocyte apoptosis was decreased by HA-CS-IL-1Ra microspheres. Moreover, HA-CS-IL-1Ra microspheres blocked IL-1β-induced chondrocyte apoptosis by increasing B-cell lymphoma 2 (Bcl-2) and decreasing Bcl-2-associated X protein and caspase-3 expressions at mRNA and protein levels, as indicated by reverse-transcription quantitative polymerase chain reaction and western blot analysis, respectively. The results of the present study indicated that HA-CS-IL-1Ra microspheres as a controlled release system of IL-1Ra possess potential anti-inflammatory and antiapoptotic properties in rat chondrocytes due to their ability to regulate inflammatory factors and apoptosis associated genes.

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