pH-Responsive and Degradable Polyurethane Film With Good Tensile Properties for Drug Delivery in vitro

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.

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Evaluation of pH-responsive liposomes containing amino acid-based zwitterionic lipids for improving intracellular drug delivery in vitro and in vivo

Journal of Controlled Release ◽

10.1016/j.jconrel.2009.10.023 ◽

2010 ◽

Vol 142 (2) ◽

pp. 267-276 ◽

Cited By ~ 87

Author(s):

Yosuke Obata ◽

Shoji Tajima ◽

Shinji Takeoka

Keyword(s):

Drug Delivery ◽

Amino Acid ◽

Ph Responsive ◽

Intracellular Drug Delivery ◽

Zwitterionic Lipids

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A Tunable pH-Responsive Nanomaterials for Cancer Delivery

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.750-752.1476 ◽

2013 ◽

Vol 750-752 ◽

pp. 1476-1479 ◽

Cited By ~ 1

Author(s):

Bin Liu ◽

Guan Hui Gao ◽

Peng Liu ◽

Hu Qiang Yi ◽

Wei Wei ◽

...

Keyword(s):

Drug Delivery ◽

Ethylene Glycol ◽

Potential Application ◽

Ph Responsive ◽

Poly Ethylene Glycol ◽

Positive Potential ◽

Ph Values ◽

Drugs In Blood ◽

Poly Ethylene

In this paper, we successfully designed a pH-responsive micelles based on hybrid polypeptide copolymers of poly (L-lysine-4-Azepan-1-yl-butyric)-b-poly (ethylene glycol)-b-poly (L-lysine-Diisopropylamide)-b-poly (L-leucine) (PLL(A)-PEG-PLL(B)-PLLeu) for efficient drug delivery. This pH-responsive nanoparticles were able to response to different pH values (pH=6.8 and 5.5). In vitro, these nanoparticles exhibited a stable and evenly distributed approximately 51 nm, a slightly positive potential about 10.3 mv at pH 7.4, which were crucial for the circulation of drugs in blood. While size and potential were about 130 nm and 34.7 mv at pH 6.8, which were good for drugs in membrane. Furthermore, the loading capability of DOX was up to 11.3%, and the pH-responsive release efficiency reached to 68.3% at pH 5.5. The results indicated that these micelles had huge potential application in cancer delivery.

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Improved in vivo tumor therapy via host–guest complexation

Journal of Materials Chemistry B ◽

10.1039/c5tb02611c ◽

2016 ◽

Vol 4 (15) ◽

pp. 2691-2696 ◽

Cited By ~ 21

Author(s):

Yong Yao ◽

Yang Wang ◽

Ruibo Zhao ◽

Li Shao ◽

Ruikang Tang ◽

...

Keyword(s):

Drug Delivery ◽

Drug Delivery System ◽

Intracellular Ph ◽

Tumor Therapy ◽

Controlled Drug Delivery ◽

Water Soluble ◽

Ph Responsive ◽

Mesoporous Nanoparticles

A decomposable and intracellular pH-responsive drug delivery system by immobilizing a water-soluble pillar[5]arene onto hollow mesoporous nanoparticles through host–guest complexation was successfully prepared and its application in controlled drug delivery in vitro and in vivo was also investigated.

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Fabrication of a pH responsive DOX conjugated PEGylated palladium nanoparticle mediated drug delivery system: an in vitro and in vivo evaluation

RSC Advances ◽

10.1039/c5ra05803a ◽

2015 ◽

Vol 5 (56) ◽

pp. 44998-45014 ◽

Cited By ~ 31

Author(s):

Krishnamurthy Shanthi ◽

Karuppaiya Vimala ◽

Dhanaraj Gopi ◽

Soundarapandian Kannan

Keyword(s):

Drug Delivery ◽

Drug Delivery System ◽

Delivery System ◽

Hela Cells ◽

Ph Responsive ◽

Palladium Nanoparticle ◽

In Vivo Evaluation ◽

Induced Apoptosis

Schematic illustration of the possible mechanism of pH based drug delivery system of DOX conjugated PEGylated PdNPs induced apoptosis in HeLa cells.

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Smart Microneedles with Porous Polymer Coatings for pH-Responsive Drug Delivery

Polymers ◽

10.3390/polym11111834 ◽

2019 ◽

Vol 11 (11) ◽

pp. 1834 ◽

Cited By ~ 8

Author(s):

Ullah ◽

Khan ◽

Choi ◽

Kim

Keyword(s):

Drug Delivery ◽

Controlled Release ◽

Drug Release ◽

Sodium Bicarbonate ◽

Porous Polymer ◽

Polymer Layer ◽

Ph Responsive ◽

Acidic Microenvironment ◽

Model Drug

: This work demonstrates a simple approach for coating a porous polymer layer on stainless-steel (SS) microneedles characterized by a pH-responsive formulation for self-regulated drug delivery. For many drug-delivery applications, the release of therapeutic agents in an acidic microenvironment is desirable. Acid-sensitive polymers and hydrogels were extensively explored, but easily prepared polymeric microcarriers that combine acid sensitivity and biodegradability are rare. Here, we describe a simple and robust method of coating a porous polymer layer on SS microneedles (MNs) that release a model drug (lidocaine) in a pH-responsive fashion. It was constructed by packing the model drug and a pH-sensitive component (sodium bicarbonate) into the pores of the polymer layer. When this acid-sensitive formulation was exposed to the acidic microenvironment, the consequent reaction of protons (H+) with sodium bicarbonate (NaHCO3) yielded CO2. This effect generated pressure inside the pores of the coating and ruptured the thin polymer membrane, thereby releasing the encapsulated drug. Scanning electron micrographs showed that the pH-sensitive porous polymer-coated MNs exposed to phosphate-buffered saline (PBS) at pH 7.4 were characterized by closed pores. However, MNs exposed to PBS at pH 5.5 consisted of open pores and the thin membrane burst. The in vitro studies demonstrated the pH sensitivity of the drug release from porous polymer-coated MNs. Negligible release was observed for MNs in receiving media at pH 7.4. In contrast, significant release occurred when the MNs were exposed to acidic conditions (pH 5.5). Additionally, comparable results were obtained for drug release in vitro in porcine skin and in PBS. This revealed that our developed pH-responsive porous polymer-coated MNs could potentially be used for the controlled release of drug formulations in an acidic environment. Moreover, the stimuli-responsive drug carriers will enable on-demand controlled release profiles that may enhance therapeutic effectiveness and reduce systemic toxicity.

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Synthesis of Chitosan-Polyvinyl Alcohol Copolymers for Smart Drug Delivery Application

Polymers and Polymer Composites ◽

10.1177/096739111702500311 ◽

2017 ◽

Vol 25 (3) ◽

pp. 241-246 ◽

Cited By ~ 4

Author(s):

Neha Mulchandani ◽

Nimish Shah ◽

Tejal Mehta

Keyword(s):

Drug Delivery ◽

Drug Release ◽

Polyvinyl Alcohol ◽

Morphological Changes ◽

Crosslinking Agent ◽

Ph Responsive ◽

Thermal Transitions ◽

Scanning Calorimetry ◽

Model Drug

Chitosan is a natural polymer obtained from exoskeletons of crustaceans and polyvinyl alcohol (PVA) is a synthetic polymer which has excellent film forming ability along with non-toxic nature. The current work focuses on synthesizing a smart polymer by copolymerization of natural and synthetic polymers and exploring its applications in drug delivery. The copolymers were blended in different ratios and were synthesized using ammonium ceric nitrate as initiator and glutaraldehyde as a crosslinking agent which were converted to films by casting method. Amoxicillin, as a model drug was incorporated to the copolymerized films to study the in-vitro drug release. The films obtained were evaluated by varying the pH to study the pH responsive nature of films. Drug release studies were performed to obtain the release profile of drug; water uptake capacity of the copolymerized film were measured to determine the swelling behaviour of the films. The films were further characterized using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Differential Scanning Calorimetry (DSC) to identify the structural and morphological changes along with thermal transitions. The results indicate that the synthesized copolymers are pH responsive in nature having great potential for application in controlled and targeted drug delivery.

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