scholarly journals 4-n-Butylresorcinol-Based Linear and Graft Polymethacrylates for Arbutin and Vitamins Delivery by Micellar Systems

Polymers ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 330 ◽  
Author(s):  
Justyna Odrobińska ◽  
Łukasz Mielańczyk ◽  
Dorota Neugebauer
Keyword(s):  
Click Reaction ◽  
Skin Condition ◽  
Amphiphilic Copolymers ◽  
Solution Ph ◽  
Polymeric Systems ◽  
Micellar Systems ◽  
Poly Ethylene ◽  
Positive Effect ◽  
Active Substances

A novel initiator, bromoester modified 4-n-butylresorcinol (4nBREBr2), was prepared and utilized in controlled atom transfer radical polymerization (ATRP) to obtain three series of amphiphilic copolymers. The V-shaped copolymers of methyl methacrylate (MMA), 2-hydroxyethyl methacrylate (HEMA), and poly(ethylene glycol) methyl ether methacrylate (MPEGMA), abbreviated to P(HEMA–co–MMA), P(HEMA–co–MPEGMA), and P(MMA–co–MPEGMA), were synthesized. Moreover, P((HEMA–graft–PEG)–co–MMA) graft copolymers were prepared by combining the pre-polymerization modification of HEMA and a “click” reaction using a “grafting onto” approach. All copolymers could form micelles with encapsulated active substances (vitamin C (VitC), vitamin E (VitE), arbutin (ARB)), which are used in cosmetology. In vitro studies carried out in a PBS solution (pH 7.4) demonstrates that in most cases the maximum release of active substance was after 1 h. The polymeric systems presenting satisfactory encapsulation characteristics and release profiles are attractive micellar carriers of cosmetic substances, which show a positive effect on the skin condition.

scholarly journals Micellar Carriers Based on Amphiphilic PEG/PCL Graft Copolymers for Delivery of Active Substances

Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2876 ◽  
Author(s):  
Justyna Odrobińska ◽  
Dorota Neugebauer
Keyword(s):  
Molecular Weight ◽  
Graft Copolymers ◽  
Drug Loading ◽  
Polymer System ◽  
Amphiphilic Copolymers ◽  
Bioactive Substances ◽  
Click Reactions ◽  
Micellar Systems ◽  
Active Substances

Amphiphilic copolymers of alkyne functionalized 2-hydroxyethyl methacrylate (AlHEMA) and poly(ethylene glycol) methyl ether methacrylate (MPEGMA) with graft or V-shaped graft topologies were synthesized. The functionalization of poly(ε-caprolactone) (PCL) with azide group enabled attachment to P(AlHEMA-co-MPEGMA) copolymers via a “click” alkyne-azide reaction. The introduction of PCL as a second side chain type in addition to PEG resulted in heterografted copolymers with modified properties such as biodegradability. “Click” reactions were carried out with efficiencies between 17–70% or 32–50% (for lower molecular weight PCL, 4000 g/mol, or higher molecular weight PCL, 9000 g/mol, respectively) depending on the PEG grafting density. The graft copolymers were self-assembled into micellar superstructures with the ability to encapsulate active substances, such as vitamin C (VitC), arbutin (ARB) or 4-n-butylresorcinol (4nBRE). Drug loading contents (DLC) were obtained in the range of 5–55% (VitC), 39–91% (ARB) and 42–98% (4nBRE). In vitro studies carried out in a phosphate buffer saline (PBS) solution (at pH 7.4 or 5.5) gave the maximum release levels of active substances after 10–240 min depending on the polymer system. Permeation tests in Franz chambers indicated that the bioactive substances after release by micellar systems penetrated through the artificial skin membrane in small amounts, and a majority of the bioactive substances remained inside the membrane, which is satisfactory for most cosmetic applications.

scholarly journals PEG Grafted Polymethacrylates Bearing Antioxidants as a New Class of Polymer Conjugates for Application in Cosmetology

Materials ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 3455 ◽  
Author(s):  
Justyna Odrobińska ◽  
Dorota Neugebauer
Keyword(s):  
Release Kinetics ◽  
Amphiphilic Copolymers ◽  
Click Reactions ◽  
Polymer Carriers ◽  
New Class ◽  
Polymer Conjugates ◽  
Poly Ethylene ◽  
Esterification Reactions ◽  
Neutral Conditions

The amphiphilic copolymers of poly(ethylene glycol) methyl ether methacrylate (MPEGMA) and alkyne functionalized 2-hydroxyethyl methacrylate (AlHEMA) were synthesized by controlled atom transfer radical polymerization (ATRP). The reactions were carried out using the standard ATRP initiator ethyl α-bromoisobutyrate, (EiBBr) and the “bio”initiator bromoester derivative of 4-n-butylresorcinol (4nBREBr2). Two substances with antioxidant activity used in cosmetology, (±)-α-lipoic acid (LA) and ferulic acid (FA), were subjected to esterification reactions to introduce azide groups. The “click” reactions between the alkyne contained copolymers and functionalized acids (LA-N3, FA-N3) were performed to obtain polymer-antioxidant conjugates (P((HEMA-click-FA)-co-MPEGMA) and P((HEMA-click-LA)-co-MPEGMA)). The conjugation was performed with an efficiency of 20–75%. In vitro experiments in a phosphate buffer saline (PBS) solution at neutral conditions demonstrated that the sufficient release was reached after 2.5 h for FA and 1 h for LA. The rapid release kinetics as well as the polymer carriers, which were applied to regulate the delivery of antioxidant substances, are beneficial in cosmetology.

scholarly journals Tiamulin fumarat – new makrolide on bovine mastitis therapy in vivo and in vitro

2020 ◽  
Vol 17 ◽  
pp. 00203
Author(s):  
Vera Kriukova ◽  
Nadezda Kuznechova ◽  
Viktoriya Gaponova ◽  
Lilia Sabyrzyanova
Keyword(s):  
Virulence Factors ◽  
Antibacterial Effect ◽  
Bovine Mastitis ◽  
Leningrad Region ◽  
Negative Consequences ◽  
Chemotherapy Drugs ◽  
Positive Effect ◽  
Active Substances

Antibiotics nowadays are widely used for the treatment of mastitis in cows, which, along with a positive effect, cause negative consequences to the organism of an animal, can be consumed by people and interacts the cultural qualities of microorganisms However, it is almost impossible to refuse from antibacterial therapy of mastitis with chemotherapy drugs. And the variety range of chemotherapy drugs for mastitis therapy today is very wide. Since we conduct monitoring devoted to full characteristics of the strains of Streptococcus spp., isolated from bovine mastitis milk of the geographical zone of Leningrad region, Russia. That is, we analyses received data on the cultural, microbiological, serological, virulence factors, and sensibility to main used in practice antibiotics and to new ones. Taking into account the already proven resistance of microorganisms to antibiotics, the biological industry offers antibacterial drugs based on new active substances for use in the treatment of cow mastitis. In the assay described in this paper, we set a goal-to investigate the antibacterial effect of tiamulin fumarat to clinical isolates of streptococci received from milk of cows with mastitis, and to determine its clinical efficacy on cows with mastitis of the bacteriological etiology

scholarly journals Thiol-ene Reaction: An Efficient Tool to Design Lipophilic Polyphosphoesters for Drug Delivery Systems

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1750
Author(s):  
Stéphanie Vanslambrouck ◽  
Raphaël Riva ◽  
Bernard Ucakar ◽  
Véronique Préat ◽  
Mick Gagliardi ◽  
...  
Keyword(s):  
Click Reaction ◽  
Drug Loading ◽  
Water Soluble ◽  
Amphiphilic Copolymers ◽  
Poorly Water Soluble Drugs ◽  
Ene Reaction ◽  
Water Soluble Drugs ◽  
Poorly Water Soluble ◽  
Poly Ethylene

Poly(ethylene glycol)-b-polyphosphoester (PEG-b-PPE) block copolymer nanoparticles are promising carriers for poorly water soluble drugs. To enhance the drug loading capacity and efficiency of such micelles, a strategy was investigated for increasing the lipophilicity of the PPE block of these PEG-b-PPE amphiphilic copolymers. A PEG-b-PPE copolymer bearing pendant vinyl groups along the PPE block was synthesized and then modified by thiol-ene click reaction with thiols bearing either a long linear alkyl chain (dodecyl) or a tocopherol moiety. Ketoconazole was used as model for hydrophobic drugs. Comparison of the drug loading with PEG-b-PPE bearing shorter pendant groups is reported evidencing the key role of the structure of the pendant group on the PPE backbone. Finally, a first evidence of the biocompatibility of these novel PEG-b-PPE copolymers was achieved by performing cytotoxicity tests. The PEG-b-PPE derived by tocopherol was evidenced as particularly promising as delivery system of poorly water-soluble drugs.

scholarly journals Well-Defined Diblock Poly(ethylene glycol)-b-Poly(ε-caprolactone)-Based Polymer-Drug Conjugate Micelles for pH-Responsive Delivery of Doxorubicin

Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1510 ◽  
Author(s):  
Amin Jafari ◽  
Lingyue Yan ◽  
Mohamed Alaa Mohamed ◽  
Yun Wu ◽  
Chong Cheng
Keyword(s):  
Ethylene Glycol ◽  
Diblock Copolymer ◽  
Click Reaction ◽  
Ph Responsive ◽  
Poly Ethylene Glycol ◽  
Polymer Backbone ◽  
Drug Conjugate ◽  
Wide Range ◽  
Poly Ethylene

Nanoparticles have emerged as versatile carriers for various therapeutics and can potentially treat a wide range of diseases in an accurate and disease-specific manner. Polymeric biomaterials have gained tremendous attention over the past decades, owing to their tunable structure and properties. Aliphatic polyesters have appealing attributes, including biodegradability, non-toxicity, and the ability to incorporate functional groups within the polymer backbone. Such distinctive properties have rendered them as a class of highly promising biomaterials for various biomedical applications. In this article, well-defined alkyne-functionalized poly(ethylene glycol)-b-poly(ε-caprolactone) (PEG-b-PCL) diblock copolymer was synthesized and studied for pH-responsive delivery of doxorubicin (DOX). The alkyne-functionalized PEG-b-PCL diblock copolymer was prepared by the synthesis of an alkyne-functionalized ε-caprolactone (CL), followed by ring-opening polymerization (ROP) using PEG as the macroinitiator. The alkyne functionalities of PEG-b-PCL were modified through copper(I)-catalyzed alkyne-azide cycloaddition (CuAAC) click reaction to graft aldehyde (ALD) groups and obtain PEG-b-PCL-g-ALD. Subsequently, DOX was conjugated on PEG-b-PCL-g-ALD through the Schiff base reaction. The resulting PEG-b-PCL-g-DOX polymer-drug conjugate (PDC) self-assembled into a nano-sized micellar structure with facilitated DOX release in acidic pH due to the pH-responsive linkage. The nanostructures of PDC micelles were characterized using transmission electron microscopy (TEM) and dynamic light scattering (DLS). In vitro studies of the PDC micelles, revealed their improved anticancer efficiency towards MCF-7 cells as compared to free DOX.

scholarly journals Synthesis of Novel pH-Tunable Thermoresponsive Hydroxyl-Terminated Hyperbranched Polyether

Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 895
Author(s):  
Xiuzhong Zhu ◽  
Xiao Duan ◽  
Ting Bai ◽  
Xuan Zhang ◽  
Tong Wang ◽  
...  
Keyword(s):  
Light Scattering ◽  
Ph Value ◽  
Click Reaction ◽  
A549 Cells ◽  
Size Exclusion ◽  
Solution Ph ◽  
One Pot ◽  
Vis Spectroscopy ◽  
Hyperbranched Polyether

In this study, a new pH-tunable thermoresponsive hydroxyl-terminated hyperbranched polyether (HTHP 2) was successfully prepared via a one-pot cationic polymerization technique and postmodification. In the first step, hydroxyl-terminated hyperbranched polyether containing double bonds (HTHP 1) were synthesized. Then, through thiol-ene “click” reaction, pH-responsive carboxyl groups were introduced to the target polymer of HTHP 2. The products were characterized via Fourier-transform infrared spectra (FTIR), nuclear magnetic resonance (NMR), and size-exclusion chromatography-multiangle laser light scattering (SEC-MALLS). Moreover, dynamic light scattering (DLS) and UV–Vis spectroscopy was employed to study the pH- and thermoresponsiveness in detail. Results showed that HTHP 2 possessed typical pH-controllable thermoresponsive behavior. By regulating the solution pH value range 3.0–5.4, LCST of HTHP 2 could be changed from 12.8 to 68.0 °C. Meanwhile, the cell viabilities of A549 cells were more than 80% for in vitro cytotoxicity tests of HTHP 2, suggested that HTHP 2 polymers are of good biocompatibility for up to 24 h.

scholarly journals Micellar Carriers of Active Substances Based on Amphiphilic PEG/PDMS Heterograft Copolymers: Synthesis and Biological Evaluation of Safe Use on Skin

2021 ◽  
Vol 22 (3) ◽  
pp. 1202
Author(s):  
Justyna Odrobińska ◽  
Magdalena Skonieczna ◽  
Dorota Neugebauer
Keyword(s):  
Drug Loading ◽  
In Vitro Release ◽  
Cycloaddition Reaction ◽  
Physicochemical Characterization ◽  
Biological Evaluation ◽  
Amphiphilic Copolymers ◽  
Proliferation Capacity ◽  
Biological Studies ◽  
Active Substances

Amphiphilic copolymers containing polydimethylsiloxane (PDMS) and polyethylene glycol methyl ether (MPEG) were obtained via an azide-alkyne cycloaddition reaction between alkyne-functionalized copolymer of MPEG methacrylate and azide-functionalized PDMS. “Click” reactions were carried out with an efficiency of 33–47% increasing grafting degrees. The grafted copolymers were able to carry out the micellization and encapsulation of active substances, such as vitamin C (VitC), ferulic acid (FA) and arginine (ARG) with drug loading content (DLC) in the range of 2–68% (VitC), and 51–89% (FA or ARG). In vitro release studies (phosphate buffer saline, PBS; pH = 7.4 or 5.5) demonstrated that the maximum release of active substances was mainly after 1–2 h. The permeability of released active substances through membrane mimicking skin evaluated by transdermal tests in Franz diffusion cells indicated slight diffusion into the solution (2–16%) and their remaining in the membrane. Studies on the selected carrier with FA showed no negative effect on cell viability, proliferation capacity or senescence, as well as cell apoptosis/necrosis differences or cell cycle interruption in comparison with control cells. These results indicated that the presented micellar systems are good candidates for carriers of cosmetic substances according to physicochemical characterization and biological studies.

A comparison of covalent and noncovalent strategies for paclitaxel release using poly(ester amide) graft copolymer micelles

2015 ◽  
Vol 93 (4) ◽  
pp. 399-405 ◽  
Author(s):  
Abdolrasoul Soleimani ◽  
Mahmoud M. Abd Rabo Moustafa ◽  
Aneta Borecki ◽  
Elizabeth R. Gillies
Keyword(s):  
Ethylene Oxide ◽  
Graft Copolymer ◽  
Drug Carriers ◽  
Prolonged Release ◽  
Amphiphilic Copolymers ◽  
Release Rates ◽  
Drug Molecules ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

Micelles formed from amphiphilic copolymers are promising for the delivery of drug molecules, potentially leading to enhanced properties and efficacies. Critical aspects of these systems include the use of biocompatible, biodegradable polymer backbones as well as the ability to control the incorporation of drugs and their release rates. In this work, a poly(ester amide)–poly(ethylene oxide) graft copolymer with paclitaxel conjugated via ester linkages was prepared and assembled into micelles. For comparison, micelles with physically encapsulated paclitaxel were also prepared. The release rates of these two systems were studied, and the micelles with covalently conjugated paclitaxel exhibited a prolonged release of the drug in comparison to the noncovalent system, which rapidly released the payload. In vitro studies suggested that the poly(ester amide)–poly(ethylene oxide) copolymers were nontoxic, whereas the toxicities of the drug-loaded micelles were dependent on their release rates. Overall, these systems are promising for further development as anticancer drug carriers.

scholarly journals Retinol-Containing Graft Copolymers for Delivery of Skin-Curing Agents

Pharmaceutics ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 378 ◽  
Author(s):  
Justyna Odrobińska ◽  
Katarzyna Niesyto ◽  
Karol Erfurt ◽  
Agnieszka Siewniak ◽  
Anna Mielańczyk ◽  
...  
Keyword(s):  
Graft Copolymers ◽  
Polymeric Systems ◽  
Micellar Systems ◽  
Self Assembling ◽  
Amphiphilic Graft Copolymers ◽  
Initial Monomer ◽  
Skin Lightening ◽  
Phosphate Buffered Saline ◽  
Fast Release

The new polymeric systems for delivery in cosmetology applications were prepared using self-assembling amphiphilic graft copolymers. The synthesis based on “click” chemistry reaction included grafting of azide-functionalized polyethylene glycol (PEG-N3) onto multifunctional polymethacrylates containing alkyne units. The latter ones were obtained via atom transfer radical polymerization (ATRP) of alkyne-functionalized monomers, e.g., ester of hexynoic acid and 2-hydroxyethyl methacrylate (AlHEMA) with methyl methacrylate (MMA), using bromoester-modified retinol (RETBr) as the initiator. Varying the content of alkyne moieties adjusted by initial monomer ratios of AlHEMA/MMA was advantageous for the achievement of a well-defined grafting degree. The designed amphiphilic graft copolymers P((HEMA-graft-PEG)-co-MMA), showing tendency to micellization in aqueous solution at room temperature, were encapsulated with arbutin (ARB) or vitamin C (VitC) with high efficiencies (>50%). In vitro experiments carried out in the phosphate-buffered saline solution (PBS) at pH 7.4 indicated the maximum release of ARB after at least 20 min and VitC within 10 min. The fast release of the selected antioxidants and skin-lightening agents by these micellar systems is satisfactory for applications in cosmetology, where they can be used as the components of masks, creams, and wraps.

Platelet Aggregation Induced in Vitro by Therapeutic Ultrasound

1977 ◽  
Vol 38 (03) ◽  
pp. 0640-0651 ◽  
Author(s):  
B. V Chater ◽  
A. R Williams
Keyword(s):  
Platelet Aggregation ◽  
Direct Action ◽  
Adenosine Diphosphate ◽  
Ultrasonic Cavitation ◽  
Related Phenomenon ◽  
Release Reaction ◽  
Physical Conditions ◽  
Platelet Aggregates ◽  
Active Substances

SummaryPlatelets were found to aggregate spontaneously when exposed to ultrasound generated by a commercial therapeutic device. At a given frequency, aggregation was found to be a dose-related phenomenon, increasing intensities of ultrasound inducing more extensive and more rapid aggregation. At any single intensity, the extent aggregation was increased as the frequency of the applied ultrasound was decreased (from 3.0 to 0.75 MHz).Ultrasound-induced platelet aggregation was found to be related to overall platelet sensitivity to adenosine diphosphate. More sensitive platelets were found to aggregate spontaneously at lower intensities of sound, and also the maximum extent of aggregation was found to be greater. Examination of ultrasound-induced platelet aggregates by electron microscopy demonstrated that the platelets had undergone the release reaction.The observation that haemoglobin was released from erythrocytes in whole blood irradiated under identical physical conditions suggests that the platelets are being distrupted by ultrasonic cavitation (violent gas/bubble oscillation).It is postulated that overall platelet aggregation is the result of two distinct effects. Firstly, the direct action of ultrasonic cavitation disrupts a small proportion of the platelet population, resulting in the liberation of active substances. These substances produce aggregation, both directly and indirectly by inducing the physiological release reaction in adjacent undamaged platelets.

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