Construction of a water‐in‐oil‐in‐water (W/O/W) double emulsion system based on oyster peptides and characterization of freeze‐dried products

Author(s):  
Wen Yang ◽  
Jinzhen Li ◽  
Dingding Ren ◽  
Wenhon Cao ◽  
Haisheng Lin ◽  
...  
2019 ◽  
Author(s):  
T S ◽  
Philippa J. Hooper ◽  
Gabi Kaminski ◽  
Christopher F. van der Walle ◽  
J. Axel Zeitler

Biodegradable poly lactic-co-glycolic acid (PLGA) microspheres can be used to encapsulate peptide and offer a promising drug delivery vehicle. In this work we investigate the dynamics of PLGA microspheres prepared by freeze-drying and the molecular mobility at lower temperatures leading to the glass transition temperature, using temperature-variable terahertz time-domain spectroscopy (THz-TDS) experiments. The microspheres were prepared using a water-in-oil-in-water (w/o/w) double emulsion technique and subsequent freeze-drying of the samples. Physical characterisation was performed by morphology measurements, scanning electron microscopy (SEM), and helium pycnometry. The THz-TDS data show two distinct transition processes, T<sub>g,β</sub> in the range of 167-219 K, associated with local motions, and T<sub>g,α</sub> in the range of 313-330 K associated with large-scale motions, for the microspheres examined. Using FTIR measurements in the mid-infrared we were able to characterise the interactions between a model polypeptide, exendin-4, and the PLGA copolymer. We observe a relationship between the experimentally determined T<sub>g,β</sub> and T<sub>g,α</sub> and free volume and microsphere dynamics. <br>


Pharmaceutics ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 281
Author(s):  
Soo-Yong Park ◽  
Jiin Kang ◽  
Ji-Young Yoon ◽  
Ildoo Chung

Biodegradable polyfumarateurethane (PFU) for use as a bupivacaine delivery vehicle, synthesized using di-(2-hydroxypropyl fumarate) (DHPF), polyethylene glycol (PEG) and 1,6-hexamethylene diisocyanate (HMDI), was designed to be degradable through the hydrolysis and enzymatic degradation of the ester bonds in its polymer backbone. Using a water-in-oil-in-water double emulsion techniques, nanoparticles encapsulating water or fluorescein isothiocyanate (FITC) were fabricated to avoid the immune system owing to the presence of PEG on their surface. The morphologies of these nanoparticles were characterized by DLS, TEM, FE-SEM, and fluorescent microscopies. The present study explored the encapsulation, loading efficiency and in vitro drug release of bupivacaine encapsulated with biodegradable PFU nanoparticles for the treatment of local anesthesia. Various concentrations of bupivacaine were encapsulated into nanoparticles and their encapsulation efficiencies and drug loading were investigated. Encapsulation efficiency was highest when 2.5% bupivacaine was encapsulated. Drug release behavior from the bupivacaine-loaded PFU nanoparticles followed a sustained release profile.


2019 ◽  
Author(s):  
T S ◽  
Philippa J. Hooper ◽  
Gabi Kaminski ◽  
Christopher F. van der Walle ◽  
J. Axel Zeitler

Biodegradable poly lactic-co-glycolic acid (PLGA) microspheres can be used to encapsulate peptide and offer a promising drug delivery vehicle. In this work we investigate the dynamics of PLGA microspheres prepared by freeze-drying and the molecular mobility at lower temperatures leading to the glass transition temperature, using temperature-variable terahertz time-domain spectroscopy (THz-TDS) experiments. The microspheres were prepared using a water-in-oil-in-water (w/o/w) double emulsion technique and subsequent freeze-drying of the samples. Physical characterisation was performed by morphology measurements, scanning electron microscopy (SEM), and helium pycnometry. The THz-TDS data show two distinct transition processes, T<sub>g,β</sub> in the range of 167-219 K, associated with local motions, and T<sub>g,α</sub> in the range of 313-330 K associated with large-scale motions, for the microspheres examined. Using FTIR measurements in the mid-infrared we were able to characterise the interactions between a model polypeptide, exendin-4, and the PLGA copolymer. We observe a relationship between the experimentally determined T<sub>g,β</sub> and T<sub>g,α</sub> and free volume and microsphere dynamics. <br>


2019 ◽  
Author(s):  
T S ◽  
Philippa J. Hooper ◽  
Gabi Kaminski ◽  
Christopher F. van der Walle ◽  
J. Axel Zeitler

Biodegradable poly lactic-co-glycolic acid (PLGA) microspheres can be used to encapsulate peptide and offer a promising drug delivery vehicle. In this work we investigate the dynamics of PLGA microspheres prepared by freeze-drying and the molecular mobility at lower temperatures leading to the glass transition temperature, using temperature-variable terahertz time-domain spectroscopy (THz-TDS) experiments. The microspheres were prepared using a water-in-oil-in-water (w/o/w) double emulsion technique and subsequent freeze-drying of the samples. Physical characterisation was performed by morphology measurements, scanning electron microscopy (SEM), and helium pycnometry. The THz-TDS data show two distinct transition processes, T<sub>g,β</sub> in the range of 167-219 K, associated with local motions, and T<sub>g,α</sub> in the range of 313-330 K associated with large-scale motions, for the microspheres examined. Using FTIR measurements in the mid-infrared we were able to characterise the interactions between a model polypeptide, exendin-4, and the PLGA copolymer. We observe a relationship between the experimentally determined T<sub>g,β</sub> and T<sub>g,α</sub> and free volume and microsphere dynamics. <br>


Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 358
Author(s):  
Phui Yee Tan ◽  
Beng Ti Tey ◽  
Eng Seng Chan ◽  
Oi Ming Lai ◽  
Hon Weng Chang ◽  
...  

Calcium carbonate (CaCO3) has been utilized as a pH-responsive component in various products. In this present work, palm tocotrienols-rich fraction (TRF) was successfully entrapped in a self-assembled oil-in-water (O/W) emulsion system by using CaCO3 as the stabilizer. The emulsion droplet size, viscosity and tocotrienols entrapment efficiency (EE) were strongly affected by varying the processing (homogenization speed and time) and formulation (CaCO3 and TRF concentrations) parameters. Our findings indicated that the combination of 5000 rpm homogenization speed, 15 min homogenization time, 0.75% CaCO3 concentration and 2% TRF concentration resulted in a high EE of tocotrienols (92.59–99.16%) and small droplet size (18.83 ± 1.36 µm). The resulting emulsion system readily released the entrapped tocotrienols across the pH range tested (pH 1–9); with relatively the highest release observed at pH 3. The current study presents a potential pH-sensitive emulsion system for the entrapment and delivery of palm tocotrienols.


RSC Advances ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1952-1959
Author(s):  
Yi Zhao ◽  
Fangfang Peng ◽  
Yangchuan Ke

Emulsion with small particle size and good stability stabilized by emulsifiers was successfully prepared for EOR application.


2006 ◽  
Vol 514-516 ◽  
pp. 1005-1009 ◽  
Author(s):  
José V. Araújo ◽  
J.A. Lopes da Silva ◽  
Margarida M. Almeida ◽  
Maria Elisabete V. Costa

Porous chitosan/brushite composite scaffolds were prepared by a freeze-drying technique, starting from brushite suspensions in chitosan solutions. The obtained scaffolds showed a regular macroporous and interconnected structure with brushite particles uniformly distributed in the chitosan matrix. The variation of the brushite concentration affected the microstructure of the final freeze-dried scaffold, in particular, its porosity and its average pore size. The yield strengths of the composite scaffolds could also be improved by the increase of the brushite content.


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