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Protein-Based Nanoparticle Materials for Medical Applications
Published in Shaker A. Mousa, Raj Bawa, Gerald F. Audette, The Road from Nanomedicine to Precision Medicine, 2020
Kelsey DeFrates, Theodore Markiewicz, Pamela Gallo, Aaron Rack, Aubrie Weyhmiller, Brandon Jarmusik, Xiao Hu
The drug delivery properties of silk fibroin can be modified by changing many factors during nanoparticle synthesis. One of these factors is the pH of the silk fibroin [95]. Particles are made by salting out a fibroin solution with potassium phosphate. The pH of the particles can be controlled depending on what type of potassium phosphate is used in the salting out. Mono potassium phosphate has a pH of 4 and dibasic potassium phosphate has a pH of 9. Silk fibroin particles with a pH of 4 develop silk II rich secondary structures while silk fibroin particles with a pH of 9 developed a silk I rich secondary structure. Particles with the silk II structure or the lower pH are less chemically stable than the particles with a higher pH and the silk I structure. When a positively charged drug is loaded into a negatively charged silk fibroin particle there is a difference in the release depending on the pH of the particle. Particle with the silk II structure and low pH have an increased initial release, whereas the high pH particles have a low release. However, particles at a neutral pH of 7 had an overall increased release over the entire time not just initially.
Protein-Based Nanoparticle Materials for Medical Applications
Published in Shaker A. Mousa, Raj Bawa, Gerald F. Audette, The Road from Nanomedicine to Precision Medicine, 2019
Kelsey DeFrates, Theodore Markiewicz, Pamela Gallo, Aaron Rack, Aubrie Weyhmiller, Brandon Jarmusik, Xiao Hu
The drug delivery properties of silk fibroin can be modified by changing many factors during nanoparticle synthesis. One of these factors is the pH of the silk fibroin [95]. Particles are made by salting out a fibroin solution with potassium phosphate. The pH of the particles can be controlled depending on what type of potassium phosphate is used in the salting out. Mono potassium phosphate has a pH of 4 and dibasic potassium phosphate has a pH of 9. Silk fibroin particles with a pH of 4 develop silk II rich secondary structures while silk fibroin particles with a pH of 9 developed a silk I rich secondary structure. Particles with the silk II structure or the lower pH are less chemically stable than the particles with a higher pH and the silk I structure. When a positively charged drug is loaded into a negatively charged silk fibroin particle there is a difference in the release depending on the pH of the particle. Particle with the silk II structure and low pH have an increased initial release, whereas the high pH particles have a low release. However, particles at a neutral pH of 7 had an overall increased release over the entire time not just initially.
Compressed Solids Formulations
Published in Sarfaraz K. Niazi, Handbook of Pharmaceutical Manufacturing Formulations, Third Edition, 2019
Granulation Load lactose cellulose microcrystalline, hydroxypropyl cellulose, dyes, or dye into mixer, and blend powders. If necessary, screen or mill powders to break up agglomerates. A portion of the cellulose microcrystalline may be added at the lubrication step.Dissolve the dibasic potassium phosphate in purified water. Use this solution to granulate powders in step 1a.Size wet granulation, dry, and pass through screen and mill.Dissolve tromethamine and estropipate in water or alcohol.Load granulation from step 1c and sodium starch glycolate into mixer, and mass with step 1d. Size wet granulation, and dry. Pass the dried granulation through screen and mill.
Modeling and simulation of single droplet drying in an acoustic levitator
Published in Drying Technology, 2023
Martin Doß, Nadja Ray, Eberhard Bänsch
In this section, we present, validate, and discuss the results obtained from our direct numerical simulations. As a representative model protein, we consider phosphoglycerate kinase (PGK) whose drying and inactivation kinetics are well documented by Prihoda.[52] The droplet formulation used by Prihoda[52] contains potassium dihydrogen phosphate (KH2 PO4) as an excipient salt for pH regulation. From Pereira et al.[53] we adopt the empirical relation for the dynamic viscosity μws of the aqueous potassium phosphate solution. Table 1 lists the values of all physical parameters which are (assumed to be) constant. Following Yarin et al.,[43] we introduce the effective sound pressure level to express the ultrasound amplitude near the levitated droplet in decibel.
Influence of different PEG/salt aqueous two-phase system on the extraction of 2,3-butanediol
Published in Preparative Biochemistry & Biotechnology, 2022
Fabiana Luisa Silva, Jádina Carina Pinheiro, Monique Juna Lopes Leite, Mariane Carolina Proner, Anderson Felipe Viana da Silva, Denise Maria Guimarães Freire, Helen Treichel, Alan Ambrosi, Marco Di Luccio
PEG 4000 g mol−1 and PEG 6000 g mol−1 were purchased from Neon (BR). PEG molar mass was chosen based on the acceptable phase forming ability (important for phase separation) without considerably impacting the solution density and viscosity. Sodium citrate, ammonium sulfate, monobasic potassium phosphate, and dipotassium phosphate were purchased from Synth (BR). All the reagents are GR grade. 2,3-butanediol (B84904), 98% purity, was acquired from Sigma-Aldrich (US). Stock solutions of PEG 4000 (60% w/w), PEG 6000 (60% w/w) and citrate buffer salts pH 6.4 (27% w/w), ammonium sulfate pH 6.5 (40% w/w) and phosphate buffer pH 7.0 (27% w/w) were prepared with ultrapure water (Milli-Q, Milipore Inc., US). The choice of the concentration of the 2,3-butanediol stock solution (40 g L−1) was based on data from the literature related to its production in fermented media obtained from substrates such as glucose, fruits, and plant residues.[2,3]
Effect of complex iron on the phosphorus absorption by two freshwater algae
Published in Environmental Technology, 2021
Yongting Qiu, Zhihong Wang, Feng Liu, Zekun Wu, Hongwei Chen, Daijun Tang, Junxia Liu
Four kinds of complex iron (EDTA-Fe, ferric humate, ferric oxalate, ammonium ferric citrate) were added into the modified BG11 medium with different concentrations in the range of 0.3–1.2 mg/L as the only iron source in the medium. EDTA-Fe, ferric oxalate, ammonium ferric citrate were first prepared as a complex solution with an iron concentration of 1 g/L. Ferric humate was compounded by ferric chloride and ammonium humate according to the molar ratio of 1:1. After all the complexed iron solutions are standing, the stable clarified solution is used as the complexed iron mother liquor. The iron concentration of each stock solution was determined, and then they were added to the culture medium according to the required concentration. The phosphorus source in the experiment was potassium phosphate monobasic. The initial concentrations of P were set at 1.0 mg/L, which was sufficient for the growth of these two algae in the whole culture period [32]. The initial biomass of S. quadricauda was set at 5 × 106 cells/L, and that of A. flos-aquae was set at 2 × 107 cells/L and the medium volume of each group was 800 mL. The culture of all groups lasted for 20 days under the condition of 25°C, a radiation intensity of 1000 Lx and a light: dark regime of 12:12 h. During the experiment period, all the flasks were shaken twice each day to avoid agglomeration. Unless otherwise specified, all the experiments were repeated 3 times.