Evaluation of the potential of air jet milling of solid protein-poly(acrylate) complexes for microparticle preparation

Schlocker, Wolfgang; Gschließer, Siegfried; Bernkop‐Schnürch, Andreas

doi:10.1016/j.ejpb.2005.09.001

Cited by 28 publications

(14 citation statements)

References 21 publications

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“…Goldcoated quartz crystal sensors were used (also from Q-sense). The resonance frequency of the crystal sensor was 4.95 MHz AE 50 kHz and was excited during experimentation at the fundamental frequency, as well as the 3rd, 5th, 7th, 9th, 11th, and 13th overtones (15,25,35,45,55, and 65 MHz, respectively). The Sauerbrey equation relates change in frequency of the oscillating sensor to the change in adsorbed mass on the sensor by the following equation: Dm ¼ ÀCDf/m where Dm is the change in mass, or mass of the deposited film; C is a constant (¼ 17.7 ng cm 2 Hz À1 at f n¼1 ¼ 5 MHz), Df is the change in frequency of the oscillating system, and m is the overtone number.…”

Section: Characterization Techniquesmentioning

confidence: 99%

“…[3][4][5] Other shell-like spherical structures, such as layer-by-layerassembled capsules [6][7][8] and nanoparticle-assembled capsules, [9][10][11][12] are also possible encapsulation and delivery agents, with chemical release from these constructs demonstrated experimentally. The synthesis of spherical structures from the cross-linking of polyelectrolytes 13 to encapsulate whole cells, 14 enzymes and other proteins, [15][16][17][18][19][20][21][22] is a common practice to preserve biological or catalytic activity. In drug delivery applications, [23][24][25][26][27] spherical structures can be in the form of solid lipid particles, 28 chitosan nano and microspheres, [29][30][31][32][33][34] cross-linked polysaccharide microspheres, [35][36][37] and alginate microspheres.…”

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confidence: 99%

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Experimental and modeling analysis of diffusive release from single‐shell microcapsules

et al. 2009

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in Wiley InterScience (www.interscience.wiley.com).There is much experimental and mathematical work that describes chemical transport from multilayered films of planar geometries. There is less so, however, for chemical transport from multilayered spheres, a common structure for controlled-release materials. Based on the Sturm-Liouville approach of Ramkrishna and Amundson (1974), explicit analytical solutions for the concentration profiles and release kinetics from spherical capsules are presented. Fluorescent dye-release studies using singleshelled microspheres called nanoparticle-assembled capsules were performed to validate the model for uniformly and nonuniformly sized capsules. The combined experiment-modeling approach allows optical microscopy images and release measurements to be readily analyzed for estimating diffusion coefficients in capsule core and shell walls. V IntroductionThe availability of new types of materials with engineered composition, porosity, internal gradation, and morphology is providing exciting opportunities in encapsulation and delivery applications, like in the biotechnology arena. Unilamellar and multilamellar vesicles, for example, have long been studied as drug and chemical delivery agents, 1,2 in which the NACs were synthesized by first mixing 14 ml of 5 mg/ml of PAH solution with 35 ml of 14.2 mM citrate solution in a 250 ml beaker under gentle magnetic stirring (speed ''4'' of 0 through 10) for 10 s. The resulting suspension turned turbid instantly indicating the formation of polymer-salt aggregates. After aging these aggregates for 20 min, 35 ml of a 1 mg/ml fluorescein sodium salt (''Na-Flu'') dye solution was added under gentle magnetic stirring for 10 s. This mixture was aged for another 10 min and 35 ml of 1.2 wt % To compare our model predictions of the fractional release rate with experiments, the following parameters were required to be estimated from experiments: (i) x 1 , the ratio between the inner and outer radii, (ii) P 12 , partition coefficient between the polymer-salt aggregate and the interior of the shell, (iii) P 2b , the partition coefficient between the outer shell surface

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Section: Characterization Techniquesmentioning

confidence: 99%

mentioning

confidence: 99%

Experimental and modeling analysis of diffusive release from single‐shell microcapsules

et al. 2009

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“…Generally, peroxidase activity decreased during the process due to its relatively low stability. Schlocker et al (2006) could show that Table 1. Influences of pressure and number of passes on particle size distribution of NP and remaining drug load and activity of peroxidase after the homogenization process.…”

Section: Measurement Of Peroxidase Activitymentioning

confidence: 94%

“…Schlocker et al (2006) demonstrated that the polymer used as well as the type of added non-solvent has a great impact on the resulting drug load. Before HPH NP consisting of Ch-GSH display a protein load of 45 AE 2% (mean AE SD; n ¼ 3) could be determined, whereas NP consisting of PAA-GSH display a protein load of 49 AE 2% (mean AE SD; n ¼ 3).…”

Section: Determination Of Model Protein Loadmentioning

confidence: 98%

Preparation and evaluation of thiomer nanoparticles via high pressure homogenization

Hoyer¹,

Schlocker²,

Greindl³

et al. 2010

Journal of Microencapsulation

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The aim of this study was to establish and evaluate a high pressure homogenization method for the preparation of thiomer nanoparticles. Particles were formulated by incorporation of the model protein horseradish peroxidase in chitosan-glutathione (Ch-GSH) and poly(acrylic acid)-glutathione (PAA-GSH) via co-precipitation followed by air jet milling. The resulting microparticles were suspended in distilled water using an Ultraturax and subsequently micronized by high pressure homogenization. Finally, resulting particles were evaluated regarding size distribution, shape, zeta potential, drug load, protein activity and release behaviour. The mean particle size after 30 cycles with a pressure of 1500 bar was 538 +/- 94 nm for particles consisting of Ch-GSH and 638 +/- 94 nm for particles consisting of PAA-GSH. Nanoparticles of Ch-GSH had a positive zeta-potential of +1.03 mv, whereas nanoparticles from PAA-GSH had a negative zeta potential of -6.21 mv. The maximum protein load for nanoparticles based on Ch-GSH and based on PAA-GSH was 45 +/- 2% and 37 +/- %, respectively. The release profile of nanoparticles followed a first order release kinetic. Thiolated nanoparticles prepared by a high pressure homogenization technique were shown to be stable and provide controlled drug release characteristics. The preparation method described here might be a useful tool for a more upscaled production of nanoparticulate drug delivery systems.

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“…Traditional encapsulation methods include the emulsification/solvent evaporation (Rogers et al, 2002), jet milling (Schlocker et al, 2006), spray drying (Vehring, 2008) and freeze drying (Semyonov et al, 2010). However, these methods may present limitations, such as relatively large particle size, wide particle size distribution, degradation of the product and difficulties in complete recovery of organic solvents (Wang et al, 2013).…”

Section: Introductionmentioning

confidence: 99%

Precipitation of Capsicum Pepper Ethanolic Extract and Poly(l-Lactic Acid) by Supercritical Co2 Antisolvent Process

Aguiar

Barrales²,

Rezende³

et al. 2015

Anais Do XX Congresso Brasileiro De Engenharia Química

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-Biquinho pepper is rich in capsinoids, which present strong pharmacological effects on health. The lack of pungency assigned to capsinoids make them interesting for the application in pharmaceutical and food industries. The aim of this work was to evaluate the encapsulation of biquinho extracts by supercritical antisolvent technique using Poly(L-lactic acid) as the coating material. A lab-scale apparatus that consists of a CO 2 supply system, solution and CO 2 injection unit (coaxial nozzle with an internal diameter equal to 127 µm), and a high pressure column was used. The process parameters were: temperature and CO 2 flow rate were fixed at 40 ˚C and 20.4 g/min respectively, pressure varied from 8 to 12 MPa, and solution flow rate varied from 0.5 and 1.0 mL/min. The morphology of particles was analyzed using a scanning electron microscope. The micrographies showed that the geometry of the particles was greatly influenced by pressure and solution flow rate. At the conditions of 10 MPa and 0.75 mL/min solution flow rate, small spherical particles (diameter of approximately 5-10 µm) were observed.

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Evaluation of the potential of air jet milling of solid protein-poly(acrylate) complexes for microparticle preparation

Cited by 28 publications

References 21 publications

Experimental and modeling analysis of diffusive release from single‐shell microcapsules

Experimental and modeling analysis of diffusive release from single‐shell microcapsules

Preparation and evaluation of thiomer nanoparticles via high pressure homogenization

Precipitation of Capsicum Pepper Ethanolic Extract and Poly(l-Lactic Acid) by Supercritical Co2 Antisolvent Process

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