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Järvinen, Kristiina; Åkerman, Satu; Svarfvar, Bror; Tarvainen, Tanja; Viinikka, P.; Paronen, Petteri

doi:10.1023/a:1011995725320

Cited by 41 publications

(9 citation statements)

References 4 publications

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“…They are generally created when weak acids and bases with p K a values between 3 and 10 are incorporated into the hydrogel network [14]. The most commonly studied ionic polymers for pH-responsive behavior include poly(acrylamide) [15], poly(acrylic acid) [16], poly(methacrylic acid) [17] and poly(diethylaminoethyl methacrylate) [18]. In aqueous media of appropriate pH and ionic strength, the pendant groups ionize and develop fixed charges on the polymer network, generating electrostatic repulsive forces that are responsible for pH-dependent swelling or deswelling of the hydrogel.…”

Section: Introductionmentioning

confidence: 99%

Controlled release of doxorubicin from pH-responsive microgels

et al. 2013

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Stimuli-responsive hydrogels have enormous potential in drug delivery applications. They can be used for site-specific drug delivery due to environmental variables in the body such as pH and temperature. In this study, we have developed pH-responsive microgels for the delivery of doxorubicin (DOX) in order to optimize its anti-tumor activity while minimizing its systemic toxicity. We used a copolymer of oligo(polyethylene glycol) fumarate (OPF) and sodium methacrylate (SMA) to fabricate the pH-responsive microgels. We demonstrated that the microgels were negatively charged, and the amounts of charge on the microgels were correlated with the SMA concentration in their formulation. The resulting microgels exhibited sensitivity to the pH and ionic strength of the surrounding environment. We demonstrated that DOX was efficiently loaded into the microgels and released in a controlled fashion via an ion-exchange mechanism. Our data revealed that the DOX release was influenced by the pH and ionic strength of the solution. Moreover, we designed a phenomenological mathematical model, based on a stretched exponential function, to quantitatively analyze the cumulative release of DOX. We found a linear correlation between the maximum release of DOX calculated from the model and the SMA concentration in the microgel formulation. The anti-tumor activity of the released DOX was assessed using a human chordoma cell line. Our data revealed that OPF–SMA microgels prolonged the cell killing effect of DOX.

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Section: Introductionmentioning

confidence: 99%

Controlled release of doxorubicin from pH-responsive microgels

et al. 2013

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“…ion-exchange membranes. As such, hydrophilic PVDF membranes have been studied [1,2] and applied for non-conventional field such as drug delivery [3,4]. Introducing hydrophilic groups on hydrophobic PVDF films surface is also of biological great interest.…”

Section: Introductionmentioning

confidence: 99%

Tailoring bulk and surface grafting of poly(acrylic acid) in electron-irradiated PVDF

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Lafon

et al. 2004

Polymer

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International audienceEndowing conventional hydrophobic poly(vinylidene fluoride) (PVDF) films with hydrophilic properties was conducted using electron beam irradiation. Grafting of acrylic acid (AA) in/onto pre-irradiated PVDF films was investigated. Reaction parameters, monomer concentration and inhibitor concentration were examined. Radiation grafted films (PVDF-g-PAA) were synthesized with various grafting yields ranging from 12 to 130 wt % in presence of Mohr's salt (25 wt %). Below 80 wt % of monomer concentration, the degree of swelling was found to increase with the grafting yield. The PAA was arranged randomly in all PVDF matrix (grafting through). Above 80 wt % of monomer concentration, the PAA was grafted only onto the surface of PVDF films leading to a highly dense layer of PAA. Grafting through or surface grafting processes were achieved by varying the water fraction in the initial monomer solution. Water molecule acts not only as a carrier for the monomer but also as a plasticizer expanding the film in the three dimensions. Evidences of grafting through and surface grafting were produced using FTIR in ATR mode, SEM coupled to X-ray detection and XPS. An accurate quantification of AA units was possible up to the micromole via a Cu 2C –EDTA complex analyzed by UV–vis spectroscopy.

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“…Unfortunately, few pH-sensitive polymers have been used for drug delivery systems because of their limited sensitivity near the pH of blood (pH 7.4). For example, natural polymers (alginate [39,40], chitosan [41,42], and carrageenan [43]) and synthesized polymers (poly(acrylic acid) (AA) [44] and poly(methacrylic acid) (MAA) [45]) exhibit a high swelling property at high pH due to ionizable functional groups on the polymer backbone or side chain. These polymers are not responsive under most physiological conditions, albeit the gastrointestinal system.…”

Section: Stimuli-responsive Materials For Drug Deliverymentioning

confidence: 99%

Bioresponsive matrices in drug delivery

et al. 2010

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For years, the field of drug delivery has focused on (1) controlling the release of a therapeutic and (2) targeting the therapeutic to a specific cell type. These research endeavors have concentrated mainly on the development of new degradable polymers and molecule-labeled drug delivery vehicles. Recent interest in biomaterials that respond to their environment have opened new methods to trigger the release of drugs and localize the therapeutic within a particular site. These novel biomaterials, usually termed "smart" or "intelligent", are able to deliver a therapeutic agent based on either environmental cues or a remote stimulus. Stimuli-responsive materials could potentially elicit a therapeutically effective dose without adverse side effects. Polymers responding to different stimuli, such as pH, light, temperature, ultrasound, magnetism, or biomolecules have been investigated as potential drug delivery vehicles. This review describes the most recent advances in "smart" drug delivery systems that respond to one or multiple stimuli.

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Cited by 41 publications

References 4 publications

Controlled release of doxorubicin from pH-responsive microgels

Controlled release of doxorubicin from pH-responsive microgels

Tailoring bulk and surface grafting of poly(acrylic acid) in electron-irradiated PVDF

Bioresponsive matrices in drug delivery

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