Antibacterial Poly(ε-CL)/Hydroxyapatite Electrospun Fibers Reinforced by Poly(ε-CL)-b-Poly(Ethylene Phosphoric Acid)

In bone surgery and orthopedics, bioresorbable materials can be helpful in bone repair and countering post-op infections. Explicit antibacterial activity, osteoinductive and osteoconductive effects are essential to achieving this objective. Nonwoven electrospun (ES) fibers are receiving the close attention of physicians as promising materials for wound dressing and tissue engineering; potentially, in high contrast with dense materials, ES mats hamper regeneration of the bone extracellular matrix to a lesser extent. The use of the compositions of inherently biodegradable polyesters (poly(ε-caprolactone) PCL, poly(lactoglycolide), etc.), calcium phosphates and antibiotics is highly prospective, but the task of forming ES fibers from such compositions is complicated by the incompatibility of the main organic and inorganic ingredients, polyesters and calcium phosphates. In the present research we report the synthesis of hydroxyapatite (HAp) nanoparticles with uniform morphology, and demonstrate high efficiency of the block copolymer of PCL and poly(ethylene phosphoric acid) (PEPA) as an efficient compatibilizer for PCL/HAp mixtures that are able to form ES fibers with improved mechanical characteristics. The materials obtained in the presence of vancomycin exhibited incremental drug release against Staphylococcus aureus (St. aureus).

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A New Approach to Developing Long-Acting Injectable Formulations of Anti-HIV Drugs: Poly(Ethylene Phosphoric Acid) Block Copolymers Increase the Efficiency of Tenofovir against HIV-1 in MT-4 Cells

International Journal of Molecular Sciences ◽

10.3390/ijms22010340 ◽

2020 ◽

Vol 22 (1) ◽

pp. 340

Author(s):

Ilya Nifant’ev ◽

Andrei Siniavin ◽

Eduard Karamov ◽

Maxim Kosarev ◽

Sergey Kovalchuk ◽

...

Keyword(s):

Controlled Release ◽

Block Copolymers ◽

Phosphoric Acid ◽

Hiv Infection ◽

Targeted Delivery ◽

Release Formulation ◽

Poly Ethylene ◽

Long Acting ◽

Hiv Drugs ◽

Anti Hiv

Despite the world’s combined efforts, human immunodeficiency virus (HIV), the causative agent of AIDS, remains one of the world’s most serious public health challenges. High genetic variability of HIV complicates the development of anti-HIV vaccine, and there is an actual clinical need for increasing the efficiency of anti-HIV drugs in terms of targeted delivery and controlled release. Tenofovir (TFV), a nucleotide-analog reverse transcriptase inhibitor, has gained wide acceptance as a drug for pre-exposure prophylaxis or treatment of HIV infection. In our study, we explored the potential of tenofovir disoproxil (TFD) adducts with block copolymers of poly(ethylene glycol) monomethyl ether and poly(ethylene phosphoric acid) (mPEG-b-PEPA) as candidates for developing a long-acting/controlled-release formulation of TFV. Two types of mPEG-b-PEPA with numbers of ethylene phosphoric acid (EPA) fragments of 13 and 49 were synthesized by catalytic ring-opening polymerization, and used for preparing four types of adducts with TFD. Antiviral activity of [mPEG-b-PEPA]TFD or tenofovir disoproxil fumarate (TDF) was evaluated using the model of experimental HIV infection in vitro (MT-4/HIV-1IIIB). Judging by the values of the selectivity index (SI), TFD exhibited an up to 14-fold higher anti-HIV activity in the form of mPEG-b-PEPA adducts, thus demonstrating significant promise for further development of long-acting/controlled-release injectable TFV formulations.

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Photo-Crosslinked Polymeric Matrix with Antimicrobial Functions for Excisional Wound Healing in Mice

Nanomaterials ◽

10.3390/nano8100791 ◽

2018 ◽

Vol 8 (10) ◽

pp. 791 ◽

Cited By ~ 3

Author(s):

Ming-Hsiang Chang ◽

Yu-Ping Hsiao ◽

Chia-Yen Hsu ◽

Ping-Shan Lai

Keyword(s):

Wound Healing ◽

Wound Infection ◽

Polymer Solution ◽

Wound Dressing ◽

Glycol Diacrylate ◽

Excisional Wound ◽

Poly Ethylene ◽

Systemic Infections

Wound infection extends the duration of wound healing and also causes systemic infections such as sepsis, and, in severe cases, may lead to death. Early prevention of wound infection and its appropriate treatment are important. A photoreactive modified gelatin (GE-BTHE) was synthesized by gelatin and a conjugate formed from the 3,3′,4,4′-benzophenone tetracarboxylic dianhydride (BTDA) and the 2-hydroxyethyl methacrylate (HEMA). Herein, we investigated the photocurable polymer solution (GE-BTHE mixture) containing GE-BTHE, poly(ethylene glycol) diacrylate (PEGDA), chitosan, and methylene blue (MB), with antimicrobial functions and photodynamic antimicrobial chemotherapy for wound dressing. This photocurable polymer solution was found to have fast film-forming property attributed to the photochemical reaction between GE-BTHE and PEGDA, as well as the antibacterial activity in vitro attributed to the ingredients of chitosan and MB. Our in vivo results also demonstrated that untreated wounds after 3 days had the same scab level as the GE-BTHE mixture-treated wounds after 20 s of irradiation, which indicates that the irradiated GE-BTHE mixture can be quickly transferred into artificial scabs to protect wounds from an infection that can serve as a convenient excisional wound dressing with antibacterial efficacy. Therefore, it has the potential to treat nonhealing wounds, deep burns, diabetic ulcers and a variety of mucosal wounds.

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Surface modification of poly (ethylene terephthalate) fabric by soy protein isolate hydrogel for wound dressing application

International Journal of Polymeric Materials ◽

10.1080/00914037.2018.1493684 ◽

2018 ◽

Vol 68 (12) ◽

pp. 714-722 ◽

Cited By ~ 3

Author(s):

Mohammad-Reza Norouzi ◽

Laleh Ghasemi-Mobarakeh ◽

Hamidreza Gharibi ◽

Rokhsareh Meamar ◽

Fatemeh Ajalloueian ◽

...

Keyword(s):

Surface Modification ◽

Soy Protein ◽

Wound Dressing ◽

Ethylene Terephthalate ◽

Soy Protein Isolate ◽

Protein Isolate ◽

Poly Ethylene Terephthalate ◽

Poly Ethylene

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Effect of Some Acrylate—Poly(Ethylene Glycol) Copolymers as Superplasticizers on the Mechanical and Surface Properties of Portland Cement Pastes

Adsorption Science & Technology ◽

10.1260/0263617054353645 ◽

2005 ◽

Vol 23 (3) ◽

pp. 245-254 ◽

Cited By ~ 18

Author(s):

S.A. Abo-El-Enein ◽

S. Hanafi ◽

F.I. El-Hosiny ◽

El-Said H.M. El-Mosallamy ◽

M.S. Amin

Keyword(s):

Ethylene Glycol ◽

Portland Cement ◽

Ordinary Portland Cement ◽

Mechanical Characteristics ◽

Hardened Cement ◽

Poly Ethylene Glycol ◽

Cement Pastes ◽

Surface Areas ◽

Poly Ethylene ◽

Hardened Cement Pastes

Ordinary Portland cement (OPC) pastes with added superplasticizer were made using water/cement weight ratios of standard consistency. Three types of superplasticizer based on acrylate—poly(ethylene glycol) copolymers were used. The pastes were hydrated for various time lengths and the mechanical characteristics of the hardened cement pastes were studied and related to their pore structures. It was found that the addition of the superplasticizers to OPC improved the mechanical properties of the hardened pastes for all hydration lengths. The addition of such superplasticizers to OPC resulted in a decrease in the specific surface areas and total pore volumes of the hardened superplasticized cement pastes relative to the corresponding hardened neat cement pastes.

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Recent advances in the asymmetric phosphoric acid-catalyzed synthesis of axially chiral compounds

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.17.185 ◽

2021 ◽

Vol 17 ◽

pp. 2729-2764

Author(s):

Alemayehu Gashaw Woldegiorgis ◽

Xufeng Lin

Keyword(s):

Phosphoric Acid ◽

Asymmetric Catalysis ◽

Medicinal Chemistry ◽

High Efficiency ◽

Biologically Active ◽

Chiral Compounds ◽

Chiral Phosphoric Acid ◽

Wide Range ◽

Axially Chiral ◽

Acid Catalyzed

In recent years, the synthesis of axially chiral compounds has received considerable attention due to their extensive application as biologically active compounds in medicinal chemistry and as chiral ligands in asymmetric catalysis. Chiral phosphoric acids are recognized as efficient organocatalysts for a variety of enantioselective transformations. In this review, we summarize the recent development of chiral phosphoric acid-catalyzed synthesis of a wide range of axially chiral biaryls, heterobiaryls, vinylarenes, N-arylamines, spiranes, and allenes with high efficiency and excellent stereoselectivity.

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