A degradable brush polymer–drug conjugate for pH-responsive release of doxorubicin

2015 ◽  
Vol 6 (6) ◽  
pp. 953-961 ◽  
Author(s):  
Yun Yu ◽  
Chih-Kuang Chen ◽  
Wing-Cheung Law ◽  
Haotian Sun ◽  
Paras N. Prasad ◽  
...  
Keyword(s):  
Ph Responsive ◽  
Triggered Release ◽  
Drug Conjugate ◽  
Brush Polymer

We report the synthesis, characterization andin vitroassessment of a degradable brush polymer–drug conjugate which can enable acid-triggered release of doxorubicin (DOX).

scholarly journals pH-Responsive “Smart” Hydrogel for Controlled Delivery of Silver Nanoparticles to Infected Wounds

Antibiotics ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 49
Author(s):  
Hanif Haidari ◽  
Zlatko Kopecki ◽  
Adam T. Sutton ◽  
Sanjay Garg ◽  
Allison J. Cowin ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Pathogenic Bacteria ◽  
Current Treatment ◽  
Ph Responsive ◽  
Triggered Release ◽  
Smart Hydrogel ◽  
Infected Wounds ◽  
Long Time ◽  
New Material

Persistent wound infections have been a therapeutic challenge for a long time. Current treatment approaches are mostly based on the delivery of antibiotics, but these are not effective for all infections. Here, we report the development of a sensitive pH-responsive hydrogel that can provide controlled, pH-triggered release of silver nanoparticles (AgNPs). This delivery system was designed to sense the environmental pH and trigger the release of AgNPs when the pH changes from acidic to alkaline, as occurs due to the presence of pathogenic bacteria in the wound. Our results show that the prepared hydrogel restricts the release of AgNPs at acidic pH (pH = 4) but substantially amplifies it at alkaline pH (pH = 7.4 and pH = 10). This indicates the potential use of the hydrogel for the on-demand release of Ag+ depending on the environmental pH. In vitro antibacterial studies demonstrated effective elimination of both Gram-negative and positive bacteria. Additionally, the effective antibacterial dose of Ag+ showed no toxicity towards mammalian skin cells. Collectively, this pH-responsive hydrogel presents potential as a promising new material for the treatment of infected wounds.

scholarly journals Functional polyurethane nanomicelle with pH-responsive drug delivery property

e-Polymers ◽  
2018 ◽  
Vol 18 (5) ◽  
pp. 409-417 ◽  
Author(s):  
Yifan Song ◽  
Yun Chai ◽  
Kai Xu ◽  
Puyu Zhang
Keyword(s):  
Drug Delivery ◽  
Drug Loading ◽  
Acid Group ◽  
Hydrophobic Drug ◽  
Ph Responsive ◽  
Triggered Release ◽  
New Thought ◽  
Buffering Agent ◽  
Sensitive Property

AbstractA new functional pH-responsive polyurethane-based nanomicelle has been developed with BES-Na as the functional monomer, the buffering agent with tertiary amine, and sulfonic acid group was incorporated into the hydrophilic shell as the functional agent, which resulted in polyurethane nanosystem with pH-sensitive property. Folic acid (FA) was chosen as model hydrophobic drug to evaluate the loading and pH-triggered release of the PU micelles in vitro drug loading and release. The drug loading content (LC) and the encapsulation efficiency (EE) for FA-loaded micelles in phosphate-buffered solutions were 7.68% and 27.72%, respectively, and the largest accumulative drug release percentages in pH 6.8 and pH 5.0 were 79.17% and 89.83% in 24 h, respectively. A facile and versatile approach has been provided for the design and fabrication of smart nanovehicles for effective drug delivery and opens a new thought in the design and fabrication of biodegradable polyurethanes for next generation of nanomicellar systems.

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.

Real time monitoring of peptide delivery in vitro using high payload pH responsive nanogels

2020 ◽  
Vol 11 (2) ◽  
pp. 425-432 ◽  
Author(s):  
Shegufta Farazi ◽  
Fan Chen ◽  
Henry Foster ◽  
Raelene Boquiren ◽  
Shelli R. McAlpine ◽  
...  
Keyword(s):  
Real Time ◽  
Intracellular Delivery ◽  
Peptide Delivery ◽  
High Loading ◽  
Loading Capacity ◽  
Ph Responsive ◽  
Real Time Monitoring ◽  
High Payload

A pH responsive pMAA nanogel that demonstrates high loading capacity and rapid intracellular delivery of hydrophilic peptides.

Dendritic magnetite decorated by pH-responsive PEGylated starch: a smart multifunctional nanocarrier for the triggered release of anti-cancer drugs

RSC Advances ◽  
2015 ◽  
Vol 5 (60) ◽  
pp. 48586-48595 ◽  
Author(s):  
Ali Pourjavadi ◽  
Zahra Mazaheri Tehrani ◽  
Seyed Hassan Hosseini
Keyword(s):  
Acrylic Acid ◽  
Cancer Drugs ◽  
Ph Responsive ◽  
Triggered Release ◽  
Anti Cancer ◽  
Poly Acrylic Acid

In the present study, we designed a pH-responsive drug nanocarrier based on polyamidoamine-modified Fe3O4 nanoparticles coated by PEGylated starch-co-poly(acrylic acid).

scholarly journals pH-Responsive Release of Ruthenium Metallotherapeutics from Mesoporous Silica-Based Nanocarriers

Pharmaceutics ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 460
Author(s):  
Minja Mladenović ◽  
Ibrahim Morgan ◽  
Nebojša Ilić ◽  
Mohamad Saoud ◽  
Marija V. Pergal ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Mesoporous Silica ◽  
Inductively Coupled Plasma ◽  
Drug Delivery Systems ◽  
Mesoporous Silica Nanoparticles ◽  
Release Kinetics ◽  
Delivery Systems ◽  
Emission Spectrometry ◽  
Ph Responsive

Ruthenium complexes are attracting interest in cancer treatment due to their potent cytotoxic activity. However, as their high toxicity may also affect healthy tissues, efficient and selective drug delivery systems to tumour tissues are needed. Our study focuses on the construction of such drug delivery systems for the delivery of cytotoxic Ru(II) complexes upon exposure to a weakly acidic environment of tumours. As nanocarriers, mesoporous silica nanoparticles (MSN) are utilized, whose surface is functionalized with two types of ligands, (2-thienylmethyl)hydrazine hydrochloride (H1) and (5,6-dimethylthieno[2,3-d]pyrimidin-4-yl)hydrazine (H2), which were attached to MSN through a pH-responsive hydrazone linkage. Further coordination to ruthenium(II) center yielded two types of nanomaterials MSN-H1[Ru] and MSN-H2[Ru]. Spectrophotometric measurements of the drug release kinetics at different pH (5.0, 6.0 and 7.4) confirm the enhanced release of Ru(II) complexes at lower pH values, which is further supported by inductively coupled plasma optical emission spectrometry (ICP-OES) measurements. Furthermore, the cytotoxicity effect of the released metallotherapeutics is evaluated in vitro on metastatic B16F1 melanoma cells and enhanced cancer cell-killing efficacy is demonstrated upon exposure of the nanomaterials to weakly acidic conditions. The obtained results showcase the promising capabilities of the designed MSN nanocarriers for the pH-responsive delivery of metallotherapeutics and targeted treatment of cancer.

Human primary fibroblasts in vitro express a purinergic P2X7 receptor coupled to ion fluxes, microvesicle formation and IL-6 release

1999 ◽  
Vol 112 (3) ◽  
pp. 297-305
Author(s):  
A. Solini ◽  
P. Chiozzi ◽  
A. Morelli ◽  
R. Fellin ◽  
F. Di Virgilio
Keyword(s):  
Purinergic Receptor ◽  
Morphological Changes ◽  
Human Fibroblasts ◽  
Ion Fluxes ◽  
Disulfonic Acid ◽  
Triggered Release ◽  
Primary Fibroblasts ◽  
Purinergic P2x7 Receptor ◽  
Skin Biopsies

We have investigated reponses to extracellular ATP in human fibroblasts obtained by skin biopsies. Our data show that these cells express a P2X7 purinergic receptor, as judged by (1) RT-PCR with specific primers, (2) reactivity with a specific anti-P2X7 antiserum, (3) activation by the selective P2X agonist benzoylbenzoylATP and (4) stimulation of transmembrane ion fluxes. Stimulation with benzoylbenzoylATP, and to a lesser extent with ATP, also caused striking morphological changes and increased formation of cytoplasmic microvesicles. These changes were fully reversible upon nucleotide removal. Two known blockers of P2X receptors, oxidised ATP and pyridoxalphosphate-6-azophenyl-2′,4′-disulfonic acid, inhibited the morphological changes fully and the ion fluxes partially. The residual rise in intracellular Ca2+ levels and membrane depolarization observed in the presence of the inhibitors were dependent upon activation of a P2Y-type receptor exhibiting a peculiar pharmacological profile, in that CTP was the preferred agonist. ATP stimulation triggered release of the pro-inflammatory cytokine IL-6 in fibroblasts pre-treated with PMA and bacterial endotoxin. These observations reveal a novel pathway for fibroblast activation and for their recruitment in the inflammatory response.

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