Pluronic F127 Content Research Articles

Ex Vivo and In Vivo Retention Time Evaluation of Fucoidan Isolated from Macrocystis pyrifera Through a Thermosensitive Gel System in The Vaginal Route

This study evaluated Fucoidan from Macrocystis pyrifera as a potential treatment for cervical cancer. The research aimed to examine Fucoidan’s in vivo retention capacities in poloxamer-based in situ gels for vaginal drug delivery systems. Five different thermosensitive gel formulations were developed, each with varying concentrations of Pluronic F127 and F68 polymers. The incorporation of HPMC affected the gelation temperature, viscosity, and bioadhesive strength. The accepted formula, F3, had a bioadhesive value of 5415.93 ± 98.74 dyne/cm2 and could form a gel at physiological temperature. Ex vivo animal models showed that Fucoidan components retained well on vaginal tissue. Only F1, F2, and F3 achieved the media after 8 hours of examination. In vivo evaluation showed F3 had the highest drug concentration retained in the vaginal mucosa of female rats after 8 hours (24,115 ± 4,842 g), slowly removed after 24 hours (13,014 ± 5,596 g). In conclusion, increases in the hydrophilic content of formulations led to the retained hydrogel formula, which increased drug release and lowered intravaginal elimination.

Transforming layered 2D mats into multiphasic 3D nanofiber scaffolds with tailored gradient features for tissue regeneration.

Multiphasic scaffolds with tailored gradient features hold significant promise for tissue regeneration applications. Herein, this work reports the transformation of two-dimensional (2D) layered fiber mats into three dimensional (3D) multiphasic scaffolds using a 'solids-of-revolution' inspired gas-foaming expansion technology. These scaffolds feature precise control over fiber alignment, pore size, and regional structure. Manipulating nanofiber mat layers and Pluronic F127 concentrations allows further customization of pore size and fiber alignment within different scaffold regions. The cellular response to multiphasic scaffolds demonstrates the number of cells migrated and proliferated onto the scaffolds are mainly dependent on the pore size rather than fiber alignment. In vivo subcutaneous implantation of multiphasic scaffolds to rats reveals substantial cell infiltration, neo tissue formation, collagen deposition, and new vessel formation within scaffolds, greatly surpassing the capabilities of traditional nanofiber mats. Histological examination indicates the importance of optimizing pore size and fiber alignment for promotion of cell infiltration and tissue regeneration. Overall, these scaffolds have potential applications in tissue modeling, studying tissue-tissue interactions, interface tissue engineering, and high-throughput screening for optimized tissue regeneration.

Sprayable ciprofloxacin-loaded poloxamer hydrogels for wound infection treatment.

Topical antimicrobial treatments for severe burns and chronic wounds provide effective treatment against infections, but cause pain and discomfort with application. This study aimed to develop an antimicrobial topical formulation comprising thermoreversible poloxamers (Pluronic F127 and F68) and a broad-spectrum antimicrobial agent (ciprofloxacin hydrochloride, CH), that could be sprayed to eliminate application pain while maintaining antimicrobial activity. Formulations were characterized to determine their sprayability under cold conditions, gelation temperature, final storage modulus at skin temperature, drug release profile, ex vivo permeation through impaired porcine skin, and inhibition against common bacterial pathogens that colonize wounds. All cold formulations were sprayable from simple hand-held, pump-action sprayers due to their low viscosity. Upon heating, 17 and 20% Pluronic F127 formulations produced hydrogels eight to ten degrees below skin temperature, independent of ciprofloxacin loading. Increasing concentrations of Pluronic F127 increased the final storage modulus and viscosity of the gels, while inclusion of Pluronic F68 reduced these properties, showing that hydrogel rheological properties at skin temperature can be tuned via choice of formulation. Drug release was directly correlated to the rheological properties, with stiffer gels resulting in a decrease in drug release rate. Overall, gels released about 65-90% of their load within 12 hours. Ex vivo skin permeation demonstrated that drug was well retained in impaired porcine skin, which is desired to continuously treat bacteria localized to the wound. A well-diffusion assay indicated that the hydrogels had greater bacterial inhibition against Pseudomonas aeruginosa, Escherichia coli, and two strains of Staphylococcus aureus when compared to commercial controls. Overall, the results show the potential of CH-loaded poloxamer formulations as suitable sprayable topical dressings to deliver antimicrobials directly to wounds.

Adsorption of Mixed Dispersions of Silica Nanoparticles and an Amphiphilic Triblock Copolymer at the Water–Vapor Interface

This study investigates the surface modification of hydrophilic silica nanoparticles by non-chemical adsorption of an amphiphilic triblock copolymer, Pluronic F-127, and elucidates its influence on the interfacial dispersion properties. The interaction between Pluronic F-127 and silica nanoparticles drives the formation of copolymer-decorated particles with increased hydrodynamic diameter and reduced effective charge as the copolymer concentration increases, while the opposite effect occurs as the particle concentration increases at a fixed polymer concentration. This indicates that increasing the copolymer concentration leads to an increase in the coating density, whereas increasing the particle concentration leads to a decrease. This is of paramount importance for modulating the reorganization of the Pluronic F-127 shell upon adsorption at fluid–fluid interfaces and, thus, the adsorption of the decorated nanoparticles at the interface and the rheological properties of the obtained layers. In fact, the relationship between copolymer concentration and interfacial tension, as well as the mechanical response of the interface, mirrors the patterns observed in Pluronic F-127 solutions, and only a shift mediated by the Pluronic F-127 concentration is found. This suggests that the presence of particles limits the space available for Pluronic F-127 molecules to reorganize at the interface but does not significantly affect the interfacial behavior of the particle-laden interface.

Box Behnken optimization of cubosomes for enhancing the anticancer activity of metformin: Design, characterization, and in-vitro cell proliferation assay on MDA-MB-231 breast and LOVO colon cancer cell lines

This study aimed to formulate and statistically optimize cubosomal formulations of metformin (MTF) to enhance its breast anticancer activity. A Box Behnken design was employed using Design-Expert® software. The formulation variables were glyceryl monooleate concentration (GMO) w/w%, Pluronic F-127 concentration (PF127) w/w% and Tween 80 concentration w/w% whereas Entrapment efficiency (EE%), Vesicles' size (VS) and Zeta potential (ZP) were set as the dependent responses. The design expert software was used to perform the process of optimization numerically. X ray diffraction (XRD), Transmission electron microscope (TEM), in-vitro release study, short-term stability study, and in in-vitro cell proliferation assay on the MDA-MB-231 breast cancer and LOVO cancer cell lines were used to validate the optimized cubosomal formulation. The optimized formulation had a composition of 4.35616 (w/w%) GMO, 5 (w/w%) PF127 and 7.444E-6 (w/w%) Tween 80 with a desirability of 0.733. The predicted values for EE%, VS and ZP were 78.0592%, 307.273 nm and − 26.8275 mV, respectively. The validation process carried out on the optimized formula revealed that there were less than a 5% variance from the predicted responses. The XRD thermograms showed that MTF was encapsulated inside the cubosomal vesicles. TEM images of the optimized MTF cubosomal formulation showed spherical non-aggregated nanovesicles. Moreover, it revealed a sustained release profile of MTF in comparison to the MTF solution. Stability studies indicated that optimum cubosomal formulation was stable for thirty days. Cytotoxicity of the optimized cubosomal formulation was enhanced on the MDA-MB-231 breast and LOVO cancer cell lines compared to MTF solution even at lower concentrations. However, it showed superior cytotoxic effect on breast cancer cell line. So, cubosomes could be considered a promising carrier of MTF to treat breast and colon cancers.

An Innovative Biofunctional Composite Hydrogel with Enhanced Printability, Rheological Properties, and Structural Integrity for Cell Scaffold Applications.

The present study was conducted to manipulate various biomaterials to find potential hydrogel formulations through three-dimensional (3D) bioprinting fabrication for tissue repair, reconstruction, or regeneration. The hydrogels were prepared using sodium alginate and gelatin combined with different concentrations of Pluronic F127 (6% (3 g), 8% (4 g), and 10% (5 g)) and were marked as AGF-6%, AGF-8%, and AGF-10%, respectively. The properties of the hydrogels were investigated using a contact angle goniometer, rheometer, and 3D bioprinter. In addition, the osteoblast-like cell line (MG-63) was used to evaluate the cell viability including hydrogels before and after 3D bioprinting. It was found that the ratio of contact angle was lowest at AGF-6%, and the rheological results were higher for all samples of AGF-6%, AGF-8%, and AGF-10% compared with the control sample. The printability indicated that the AGF-6% hydrogel possessed great potential in creating a cell scaffold with shape integrity. Moreover, the live/dead assay also presented the highest numbers of live cells before printing compared with after printing. However, the number of live cells on day 7 was higher than on day 1 before and after printing (** p < 0.01). Therefore, the combination of AGF-6% could be developed as a biofunctional hydrogel formulation for potential tissue regeneration applications.

MICRONEEDLES ASSISTED ENHANCEMENT OF TRANSDERMAL DELIVERY OF CURCUMIN THROUGH ORGANOGEL FORMULATION

Curcumin is a natural compound found in turmeric and has been shown to have anti-inflammatory and antioxidant properties. Topical delivery of curcumin through an organic emulsion-based gel can effectively target inflammation at specific sites on the body. The current study aims to formulate Pluronic based organogel of curcumin, whose absorption is further assisted by microneedles technology. Nine organogel formulations were prepared and optimized by 32 full factorization model to fix the ratio of lecithin[A] and Pluronic[B] concentration in order to get optimum drug release after 2 hours (Q2) and maximum release of drug after 8 hours (Q8). The in-vitro study through the Franz diffusion cell indicated a significant impact of Pluronic F-127 concentration on the release of drug. As increased concentration of Pluronic increased the viscosity of formulations which ultimately retarded the release of drug. Based on Design of Experiment (DoE) study, optimized batch containing 6.5% lecithin and 20.6% Pluronic was further studied for microneedle assisted ex-vivo skin permeation through rat skin. Permeation without microneedle poration was around 70.26% after 8 hours, which was significantly increased (around 25%) after microneedle treatment of the skin. The results indicated promising application microneedle assisted skin permeation as a non-invasive and controlled delivery of curcumin through the transdermal route. Further, in-vivo studies are recommended to further establish this promising concept, targeting a variety of inflammatory conditions, including arthritis, psoriasis, and eczema, etc., through non-invasive transdermal drug delivery systems.

Extraction of hydroxycinnamic acids (ferulic and p-coumaric) from rice straw alkaline black liquor using Pluronic F-127 for potential applications in the cosmetics industry

In the present study, ferulic (FA) and p-coumaric (pCA) acids were extracted from rice straw (Oryza sativa) alkaline black liquor by an aqueous two-phase system (ATPS) based on cloud point of surfactant/copolymer Pluronic F-127 (PF-127). An acid precipitation process was studied as a primary purification step of FA and pCA and next, an extraction of these hydroxycinnamic acids (HAs) using PF-127 in different concentrations (1.1–17.3% w/w) was performed. The results showed that in PF-127 concentration of 9.4% w/w, yield extractions of 75.8% for FA and 74.3% for pCA were achieved. In addition, FA and pCA were concentrated 2.3 and 2.5-fold, respectively, compared to their original concentrations in the liquor, resulting in a PF-127 gel containing 0.12% w/w HAs. This material will be further investigated for potential applications in the cosmetics industry as an alternative for obtaining high value-added products in a rice straw-based biorefinery. Data availabilityData will be made available on request.

Modulating and optimizing Pluronic F-68 concentrations and feeding for intensified perfusion Chinese hamster ovary cell cultures.

Perfusion culture is often performed with micro-sparger to fulfill the high oxygen demand from the densified cells. Protective additive Pluronic F-68 (PF-68) is widely used to mitigate the adverse effect in cell viability from micro-sparging. In this study, different PF-68 retention ratio in alternating tangential filtration (ATF) columns was found to be crucial for cell performance of different perfusion culture modes. The PF-68 in the perfusion medium was found retained inside the bioreactor when exchanged through ATF hollow fibers with a small pore size (50 kD). The accumulated PF-68 could provide sufficient protection for cells under micro-sparging. On the other hand, with large-pore-size (0.2μm) hollow fibers, PF-68 could pass through the ATF filtration membranes with little retention, and consequently led to compromised cell growth. To overcome the defect, a PF-68 feeding strategy was designed and successfully verified on promoting cell growth with different Chinese hamster ovary (CHO) cell lines. With PF-68 feeding, enhancements were observed in both viable cell densities (20%-30%) and productivity (~30%). A threshold PF-68 concentration of 5g/L for high-density cell culture (up to 100 × 106 cells/mL) was also proposed and verified. The additional PF-68 feeding was not observed to affect product qualities. By designing the PF-68 concentration of perfusion medium to or higher than the threshold level, a similar cell growth enhancement was also achieved. This study systematically investigated the protecting role of PF-68 in intensified CHO cell cultures, shedding a light on the optimization of perfusion cultures through the control of protective additives.

Thermosensitive Pluronic® F127-Based in situ gel formulation containing nanoparticles for the sustained delivery of paclitaxel

Bone metastasis is one of the most encountered complications among cancer patients and majority of cancer types has led to bone metastasis. Paclitaxel (PCX) is an anticancer agent commonly used in cancer treatment. However, its clinical use is restricted owing to poor water solubility. PCL NPs were investigated to cope with solubility problem of PCX. The size, polydispersity index and zeta potential of PCL were 383.8±2.4 nm, 0.253±0.122 and +51.3±6.1 mV, respectively. The PCX encapsulation efficiency was 77.2±2.1%. Subsequently, in situ gellling system was prepared by using different Pluronic F-127 concentration in order to determine the optimum ratio. İn situ gel formulation containing 20% Pluronic F-127 was selected as the optimum formulation and subjected to characterization tests. The viscosity of in situ gelling system with CS/PCX-PCL NPs at room temperature (25 °C±0.1) and at body temperature (37 °C±0.1) were found 137.00 ±3.05 cP and 890.30 ±89.61 cP at 100 rpm, respectively. According to the release results, in situ gel provided prolonged release profile compared to PCL NPs alone. Consequently, in situ gel containing CS/PCX-PCL NP elucidated in detail is a promising approach for locally applicable injectable systems.

Response Surface Methodology (RSM) Powered Formulation Development, Optimization and Evaluation of Thiolated Based Mucoadhesive Nanocrystals for Local Delivery of Simvastatin.

In oral administration systems, mucoadhesive polymers are crucial for drug localization and target-specific activities. The current work focuses on the application of thiolated xanthan gum (TXG) to develop and characterize a novel mucoadhesive nanocrystal (NC) system of simvastatin (SIM). Preparation of SIM-NC was optimized using response surface methodology (RSM) coupled with statistical applications. The concentration of Pluronic F-127 and vacuum pressure were optimized by central composite design. Based on this desirable approach, the prerequisites of the optimum formulation can be achieved by a formulation having 92.568 mg of F-127 and 77.85 mbar vacuum pressure to result in EE of 88.8747% and PS of 0.137.835 nm. An optimized formulation was prepared with the above conditions along with xanthan gum (XG) and TXG and various parameters were evaluated. A formulation containing TXG showed 98.25% of SIM at the end of 96 h. Regarding the mucoadhesion potential evaluated by measuring zeta potential, TXG-SIM-NC shoed the maximum zeta potential of 16,455.8 ± 869 mV at the end of 6 h. The cell viability percentage of TXG-SIM-NC (52.54 ± 3.4% with concentration of 50 µg/mL) was less than the plain SIM, with XG-SIM-NC showing the highest cytotoxicity on HSC-3 cells. In vivo pharmacokinetic studies confirm the enhanced bioavailability of formulated mucoadhesive systems of SIM-NC, with TXG-SIM-NC exhibiting the maximum.

Optimization of an adenovirus-vectored zoster vaccine production process with chemically defined medium and a perfusion system.

ObjectivesCells grown in chemically defined medium are sensitive to shear force, potentially resulting in decreased cell growth. We optimized the perfusion process for HEK293 cell-based recombinant adenovirus-vectored zoster vaccine (Ad-HER) production with chemically defined medium.MethodsWe first studied the pseudo-continuous strategies in shake flasks as a mimic of the bioreactor equipped with perfusion systems. Using design of experiment (DoE) in shake flasks, we obtained the regression models between Ad-HER titer/virus input–output ratio and three production process parameters: time of infection (TOI), multiplicity of infection (MOI), and virus production pH (pH). We then confirmed the effect of Pluronic F68 (PF-68) at 3.0 g/L on HEK293 cell growth and Ad-HER production in shake flasks and a 2 L benchtop bioreactor.ResultsThe optimized process was scale-up to a 2 L benchtop bioreactor with the PATFP perfusion system, which yielded cell density of 7.4 × 106 cells/mL and Ad-HER titer of 9.8 × 109 IFU/mL at 2 dpi, comparable to the bioreactor with a ATF2 system.ConclusionThis optimization strategy could be used to develop a robust process with stable cell culture performance and adenovirus titer. Increasing PF-68 concentration in chemically defined medium could protect cells from shear stress generated by perfusion system.

Embedded Core-Shell 3D Printing (eCS3DP) with Low-Viscosity Polysiloxanes.

Flexible core-shell 3D structures are essential for the development of soft sensors and actuators. Despite recent advancements in 3D printing, the fabrication of flexible 3D objects with internal architectures (such as channels and void spaces) remains challenging with liquid precursors due to the difficulty to maintain the printed structures. The difficulty of such fabrication is prominent especially when low-viscosity polysiloxane resins are used. This study presents a unique approach to applying direct ink writing (DIW) 3D printing in a three-phase system to overcome this limitation. We performed core-shell 3D printing using a low-viscosity commercial polysiloxane resin (Ecoflex 10) as shell inks combined with a coaxially extruded core liquid (Pluronic F127) in Bingham plastic microparticulate gels (ethanol gel). In the process termed embedded core-shell 3D printing (eCS3DP), we highlighted the dependence of the rheological characteristics of the three fluids on the stability of the printed core-shell filament. With the core liquid with a sufficiently high concentration of Pluronic F127 (30 w/w%; σy = 158.5 Pa), the interfacial instability between the shell liquid and core liquid was suppressed; the removal of the core liquid permitted the fabrication of perfusable channels. We identified the printing conditions to ensure lateral attachments of printed core-shell filaments. Interestingly, judicious selection of the rheological properties and flow rates of three phases allowed the formation of droplets consisting of core liquids distributed along the printed filaments. eCS3DP offers a simple route to fabricate 3D structures of a soft elastomeric matrix with embedded channels and should serve as a useful tool for DIW-based fabrication of flexible wearable devices and soft robotic components.

Enhancement of antiproliferative potential of metformin against melanoma mice B16 cells using an optimized liposomal drug delivery system.

Metformin-loaded liposomes were optimized for enhanced antiproliferative activity against melanoma. Box-Behnken design and response surface methodology were employed to optimize entrapment efficiency, ex-vivo permeation and vesicle size. The optimized formulation was prepared by both the lipid hydration method and the modified injection method for comparison. Different concentrations of Pluronic F127 were employed for modification. Selected Pluronic-modified formulation (lipid molar concentration 55 mmol, cholesterol 30% and drug loading 52.9 mg) was characterized for morphology, entrapment efficiency, permeation and vesicle size. The optimized formulation resulted in entrapment efficiency of 41.7 ± 0.01%, vesicle size of 1.405 ± 0.061 µm and percentage of permeation was 67 ± 5.5%. The improved cytotoxic effect of the selected formulation against melanoma mice B16 cell line compared with metformin solution was determined using MTT assay. Compared with the corresponding drug solution, the Pluronic-modified optimized liposomes displayed a highly efficient cytotoxic effect as evidenced by significant lowering in IC50 -887.3 ± 23.2 and 26.71 ± 0.69 μg/ml, respectively, P < 0.0001. This study introduces an optimized liposomal formulation with enhanced cytotoxic effect against melanoma B16 cell line.

Fabrication of novel anti-fouling poly(m-phenylene isophthalamide) ultrafiltration membrane modified with Pluronic F127 via coupling phase inversion and surface segregation

• PMIA/F127 membrane was prepared via NIPS combining with surface segregation. • DFT calculation was employed for designing membrane casting solution. • Influences of F127 on membrane properties were systematically investigated. • The membrane exhibited good separating performance and high antifouling ability. The novel poly( m -phenylene isophthalamide) (PMIA) ultrafiltration membrane with enhanced anti-fouling performance was successfully designed using amphiphilic block copolymer Pluronic F127 via non-solvent induced phase separation (NIPS) technique combined with induced segregation. The influences of Pluronic F127 on PMIA membrane’s microstructure and properties were systematically conducted by employing a series of characterized methods. Meanwhile, the density functional theory (DFT) calculation was employed to study the intermolecular force among the bulk PMIA, Pluronic F127 additive, solvent, and inorganic agent. Results demonstrated that Pluronic F127, functioning as both a porogen and an induced-segregation additive, could effectively affect membrane structure and property. Specifically, the resultant membrane morphologies of the sublayer gradually altered from the finger-like pore to cavity-like shape, and the pore diameter and porosity displayed a stepwise upward trend via increasing the concentration of Pluronic F127, which further induced the loss of the membrane’s mechanical strength. The filtration experiments demonstrated that the water permeation was enhanced, along with the slightly reduced rejection to bovine serum albumin (BSA) with the increasing concentration of Pluronic F127. Furthermore, the fouling resistance and stability were improved remarkably, which benefited from the enhanced hydrophilicity caused by the migration of polyethylene glycol (PEO) segment of Pluronic F127 toward membrane surface and inner-pore wall. Additionally, DFT calculation confirmed the interaction energy among the dope components, which provided theoretical support on the dope design. In summary, the Pluronic F127/PMIA ultrafiltration membrane demonstrated great potential in the field of water purification and wastewater reclamation.

Statistical optimization of nanostructured gels for enhancement of vinpocetine transnasal and transdermal permeation

Pluronic-based nanostructured gels were developed and optimized to increase the permeability of vinpocetine through the skin and the mucous layer of the nasal cavity. A modified thin-film hydration technique was utilized to prepare the nanostructured gel formulae containing different concentrations of Pluronic F127, Pluronic F68 and oleic acid. The formed nanodispersions were tested for their pH, particle size, zeta potential, polydispersity index, entrapment efficiency and gelation temperature. Box-Behnken statistical design was used to choose the optimized nasal and transdermal nanostructured gel formulae utilizing Design-Expert® software. The nasal optimized formula consisted of 2.4% oleic acid, 23.46% total surfactants and 27.13% Pluronic F68, had a gelation temperature of 35 °C which could be suitable to form in situ gel upon application into the nasal cavity. On the other hand, the transdermal optimized formula, composed of 1.77% oleic acid, 22.46% total surfactants and 11.54% Pluronic F68, formed gel at room temperature that could be suitable to be applied onto the skin. The optimized gel formulae were investigated for their in vitro drug release, rheology, morphology, histopathology and ex vivo permeation. The extent of drug permeated from the optimized formula through both nasal and skin membranes was significantly increased by 3.39 and 4.7 folds when compared to the drug suspension. Finally, the obtained findings ensured the creditable impact of the nanostructured gels as promising nanocarriers for enhancing transmucosal and transdermal vinpocetine permeation.

Exploring high pressure nebulization of Pluronic F127 hydrogels for intraperitoneal drug delivery

Peritoneal metastasis is an advanced cancer type which can be treated with pressurized intraperitoneal aerosol chemotherapy (PIPAC). Here, chemotherapeutics are nebulized under high pressure in the intraperitoneal (IP) cavity to obtain a better biodistribution and tumor penetration. To prevent the fast leakage of chemotherapeutics from the IP cavity, however, nebulization of controlled release formulations is of interest.In this study, the potential of the thermosensitive hydrogel Pluronic F127 to be applied by high pressure nebulization is evaluated. Therefore, aerosol formation is experimentally examined by laser diffraction and theoretically simulated by computational fluid dynamics (CFD) modelling. Furthermore, Pluronic F127 hydrogels are subjected to rheological characterization after which the release of fluorescent model nanoparticles from the hydrogels is determined.A delicate equilibrium is observed between controlled release properties and suitability for aerosolization, where denser hydrogels (20% and 25% w/v Pluronic F127) are able to sustain nanoparticle release up to 30 h, but cannot effectively be nebulized and vice versa. This is demonstrated by a growing aerosol droplet size and exponentially decreasing aerosol cone angle when Pluronic F127 concentration and viscosity increase. Novel nozzle designs or alternative controlled release formulations could move intraperitoneal drug delivery by high pressure nebulization forward.

Simulated synthesis of silica nanowires by lyotropic liquid crystal template method

ABSTRACT Dissipative particle dynamics simulations were adopted to study the mechanism of lyotropic liquid crystal (LLC) formation and the synthesis process of silica nanowires by LLC template method. Simulation results show that the one-dimensional (1D) LLC channel can be formed at the Pluronic F127 concentration range of 61 ∼ 67%. With the increase of Pluronic F127 concentration, the diameter of LLC channel decreases and the deformation degree increases. The effect of PEO: PPO ratio on the diameter of LLC channel is slight. The appropriate PEO: PPO ratio of Pluronic is 40:70 for the formation of 1D LLC channel, as the deformation degree of channel is the smallest in this case. The effect of polymerisation degree on the diameter and deformation degree of LLC channel is both little. With the increase of TEOS concentration, the nanowire diameter increases rapidly at first, and then increases quite slowly. This work can provide guidance for silica nanowires synthesis by LLC template method.

Effects of Poloxamer Content and Storage Time of Biodegradable Starch-Chitosan Films on Its Thermal, Structural, Mechanical, and Morphological Properties.

Biodegradable packaging prepared from starch is an alternative to fossil-based plastic packaging. However, the properties of starch packaging do not comply with the necessary physicochemical properties to preserve food. Hence, in a previous study, we reported the preparation of a composite polymer material based on starch-chitosan-pluronic F127 that was found to be an adequate alternative packaging material. In this study, we modified the physicochemical properties of this material by storing it for 16 months under ambient conditions. The results indicate that the incorporation of pluronic F127 in the blend polymer can help avoid the retrogradation of starch. Moreover, at higher concentrations of pluronic F127, wettability is reduced. Finally, after storage, the materials exhibited surface modification, which is related to a color change and an increase in solubility, as well as a slight increase in stiffness.

Influence of adding Pluronic F127 in the electrolyte on the morphology, structure and biofilm adhesion of calcium phosphate coatings

In this work, we have investigated the addition of Pluronic F127 (PF127) into the electrolyte solution on the structure, morphology and antibacterial growth of calcium phosphate (CaP) coatings synthesized by an electrochemical method on Ti substrate. Different parameters of the deposition process were investigated, which were temperature, time and PF127 wt%. The coatings were characterized by X-ray diffraction (XRD), gravimetric analysis, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In vitro antimicrobial assays against S. aureus were performed. XRD analysis confirmed the formation of dicalcium phosphate dihydrate (DCPD) or anhydrous dicalcium phosphate (DCPA) and octacalcium phosphate (OCP). The structure and morphology depended mainly on PF127 wt% and deposition temperature in lower deposition time. Interestingly, structure and morphology were not influenced by adding PF127 at higher deposition time using higher PF127 concentrations. The morphology by SEM changed from plate-like to fiber by varying the PF127 concentration as well as blocks at higher temperatures. Moreover, all coatings were crystalline, uniform and crack-free. Antibacterial assays showed that biofilm formation was prevented when a coating of PF127 is deposited on the surface. Bacterial growth depended on the phase and morphology of washed coatings. Thus, the structure, morphology and consequently bacterial growth resistance can be tailored by the use of PF127 in the electrochemical processing at shorter deposition times.