The effect of pharmaceuticals on the nanoscale structure of PEO–PPO–PEO micelles

Kumar, Praveen; Reilly, Meghan J.; Jones, Deanna N.; Robinson, Paula; Bhatia, Surita R.

doi:10.1016/j.colsurfb.2007.07.002

Cited by 79 publications

(76 citation statements)

References 14 publications

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“…Moreover, the gelation temperatures of 18% F127 containing low (0.21%, w/v), medium (0.42%, w/v), and high (1.25%, w/v) lipid concentrations of blank liposomes was found at 27.4°C, 25.8°C, and 23.1°C, respectively. In many published studies, the effect of smaller solutes, salts, cosolvents, or cell culture on the phase transform behavior of F127 has been well discussed, 41,61,63,[67][68][69] but the influence of liposomes on the self-assembling and thermogelation property of the F127 system has not been examined. Therefore, a more easy and sensitive method (DSC thermal analysis) was considered for our study in order to get more useful information about both micellization and sol-gelation transition processes that are always accompanied by the thermoreversible behavior of F127.…”

Section: Thermal Analysis Of Thermo-sensitive F127 Systemmentioning

confidence: 99%

“…In addition, a small shoulder peak representing SGT was found at a higher temperature, which appeared at the right-hand end of the CMT peak, corresponding to micelle rearrangement -a cause of thermogelation and consistent with previous reports. 41,57,71 However, thermogelation is only accompanied by a small enthalpy value; thus, it appears that DSC is less sensitive to the occurrence of the sol-gel transition, but more sensitive to the onset of rapid micelle formation.…”

Section: Thermal Analysis Of Thermo-sensitive F127 Systemmentioning

confidence: 99%

“…phenomena is that some of the water molecules would have been taken into the hydrophilic inner core of the liposome bilayer structure, so the presence of liposomes probably caused dehydration of the micelles' cores, which has been suggested as one of the major causes of gelation in these systems. 41,66 The more liposome present in the F127 solution, the more water molecules would be located within the inner core of the liposomes, and consequently the greater the extent of dehydration.…”

Section: Thermal Analysis Of Thermo-sensitive F127 Systemmentioning

confidence: 99%

“…40 A moderately concentrated solution of F127 forms a free-flowing solution at or below normal ambient temperature and is able to form a gel at body temperature, as the micelles form partially ordered cubic phases as the micellar cores dehydrate. 41 Therefore, it has been widely exploited as a topical drug delivery carrier of anticancer agents, and for the covering of burn wounds. It also has been used in rectal, ophthalmic, parenteral, and nasal administrations, as well as in subcutaneous administrations.…”

Section: Introductionmentioning

confidence: 99%

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Thermoreversible Pluronic® F127-based hydrogel containing liposomes for the controlled delivery of paclitaxel: in vitro drug release, cell cytotoxicity, and uptake studies

Nie¹,

Hsiao²,

Pan³

et al. 2011

IJN

119

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Purpose To develop an in situ gel system comprising liposome-containing paclitaxel (PTX) dispersed within the thermoreversible gel (Pluronic ® F127 gel) for controlled release and improved antitumor drug efficiency. Methods The dialysis membrane and membrane-less diffusion method were used to investigate the in vitro drug release behavior. Differential scanning calorimetry (DSC) thermal analysis was used to investigate the “micellization” and “sol/gel transition” process of in situ gel systems. In vitro cytotoxicity and drug uptake in KB cancer cells were determined by MTT, intercellular drug concentration, and fluorescence intensity assay. Results The in vitro release experiment performed with a dialysis membrane model showed that the liposomal gel exhibited the longest drug-release period compared with liposome, general gel, and commercial formulation Taxol ® . This effect is presumably due to the increased viscosity of liposomal gel, which has the effect of creating a drug reservoir. Both drug and gel release from the in situ gel system operated under zero-order kinetics and showed a correlation of release of PTX with gel, indicating a predominating release mechanism of the erosion type. Dispersing liposomes into the gel replaced larger gel itself for achieving the same gel dissolution rate. Both the critical micelle temperature and the sol/gel temperature, detected by DSC thermal analysis, were shifted to lower temperatures by adding liposomes. The extent of the shifts depended on the amount of embedded liposomes. MTT assay and drug uptake studies showed that the treatment with PTX-loaded liposomal 18% Pluronic F127 yielded cytotoxicities, intercellular fluorescence intensity, and drug concentration in KB cells much higher than that of conventional liposome, while blank liposomal 18% Pluronic F127 gel was far less than the Cremophor EL ® vehicle and empty liposomes. Conclusions A thermosensitive hydrogel with embedded liposome is a promising carrier for hydrophobic anticancer agents, to be used in parenteral formulations for treating local cancers.

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Section: Thermal Analysis Of Thermo-sensitive F127 Systemmentioning

confidence: 99%

Section: Thermal Analysis Of Thermo-sensitive F127 Systemmentioning

confidence: 99%

Section: Thermal Analysis Of Thermo-sensitive F127 Systemmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Thermoreversible Pluronic® F127-based hydrogel containing liposomes for the controlled delivery of paclitaxel: in vitro drug release, cell cytotoxicity, and uptake studies

Nie¹,

Hsiao²,

Pan³

et al. 2011

IJN

119

View full text Add to dashboard Cite

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“…The second possibility is that these smaller particles may represent PS-b-PEO micelles not loaded with PLGA. It is known that hydrophobic loading in the core, for example, with drug 49 or NPs, 27 can increase micelle size. Degradation tests in acidic media further suggest that PLGA NPs are not present in solution.…”

mentioning

confidence: 99%

Micelle-templated, poly(lactic-<em>co</em>-glycolic acid) nanoparticles for hydrophobic drug delivery

Nabar¹,

Mahajan²,

Calhoun³

et al. 2018

IJN

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Purpose Poly(lactic- co -glycolic acid) (PLGA) is widely used for drug delivery because of its biocompatibility, ability to solubilize a wide variety of drugs, and tunable degradation. However, achieving sub-100 nm nanoparticles (NPs), as might be desired for delivery via the enhanced permeability and retention effect, is extremely difficult via typical top-down emulsion approaches. Methods Here, we present a bottom-up synthesis method yielding PLGA/block copolymer hybrids (ie, “PolyDots”), consisting of hydrophobic PLGA chains entrapped within self-assembling poly(styrene- b -ethylene oxide) (PS- b -PEO) micelles. Results PolyDots exhibit average diameters <50 nm and lower polydispersity than conventional PLGA NPs. Drug encapsulation efficiencies of PolyDots match conventional PLGA NPs (ie, ~30%) and are greater than those obtained from PS- b -PEO micelles (ie, ~7%). Increasing the PLGA:PS- b -PEO weight ratio alters the drug release mechanism from chain relaxation to erosion controlled. PolyDots are taken up by model glioma cells via endocytotic mechanisms within 24 hours, providing a potential means for delivery to cytoplasm. PolyDots can be lyophilized with minimal change in morphology and encapsulant functionality, and can be produced at scale using electrospray. Conclusion Encapsulation of PLGA within micelles provides a bottom-up route for the synthesis of sub-100 nm PLGA-based nanocarriers with enhanced stability and drug-loading capacity, and tunable drug release, suitable for potential clinical applications.

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pH Switchable Water Dispersed Photocatalytic Nanoparticles

Guernelli

Menichetti

Guidetti

et al. 2022

Chemistry A European J

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Photogeneration of Reactive Oxygen Species (ROS) finds applications in fields as different as nanomedicine, art preservation, air and water depollution and surface decontamination. Here we present photocatalytic nanoparticles (NP) that are active only at acidic pH while they do not show relevant ROS photo-generation at neutral pH. This dual responsivity (to light and pH) is achieved by stabilizing the surface of TiO 2 NP with a specific organic shell during the [a

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The effect of pharmaceuticals on the nanoscale structure of PEO–PPO–PEO micelles

Cited by 79 publications

References 14 publications

Thermoreversible Pluronic® F127-based hydrogel containing liposomes for the controlled delivery of paclitaxel: in vitro drug release, cell cytotoxicity, and uptake studies

Thermoreversible Pluronic® F127-based hydrogel containing liposomes for the controlled delivery of paclitaxel: in vitro drug release, cell cytotoxicity, and uptake studies

Micelle-templated, poly(lactic-<em>co</em>-glycolic acid) nanoparticles for hydrophobic drug delivery

pH Switchable Water Dispersed Photocatalytic Nanoparticles

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The effect of pharmaceuticals on the nanoscale structure of PEO–PPO–PEO micelles

Cited by 79 publications

References 14 publications

Thermoreversible Pluronic&reg; F127-based hydrogel containing liposomes for the controlled delivery of paclitaxel: in vitro drug release, cell cytotoxicity, and uptake studies

Thermoreversible Pluronic&reg; F127-based hydrogel containing liposomes for the controlled delivery of paclitaxel: in vitro drug release, cell cytotoxicity, and uptake studies

Micelle-templated, poly(lactic-<em>co</em>-glycolic acid) nanoparticles for hydrophobic drug delivery

pH Switchable Water Dispersed Photocatalytic Nanoparticles

Contact Info

Product

Resources

About

Thermoreversible Pluronic® F127-based hydrogel containing liposomes for the controlled delivery of paclitaxel: in vitro drug release, cell cytotoxicity, and uptake studies

Thermoreversible Pluronic® F127-based hydrogel containing liposomes for the controlled delivery of paclitaxel: in vitro drug release, cell cytotoxicity, and uptake studies