SDS gel electrophoresis is a commonly used approach for monitoring purity and apparent molecular mass (Mr) of proteins, especially in the field of quality control of biopharmaceutical proteins. The ...technological installation of CE‐SDS as the replacement of the slab gel technique (SDS‐PAGE) is still in progress, leading to a continuous improvement of CE‐SDS instruments. Various CE‐SDS instruments, namely Maurice (CE‐SDS/CE‐SDS PLUS) and Wes by ProteinSimple as well as the microchip gel electrophoresis system LabChip® GXII Touch™ HT by PerkinElmer were tested for precision and repeatability compared to SDS‐PAGE (Bio‐Rad). For assessing these quality control parameters, standard model proteins with minor post‐translational modifications were used. Overall, it can be concluded that the CE‐SDS‐based methods are similar to SDS‐PAGE with respect to these parameters. Quality characteristics of test systems gain more significance by testing proteins that do not behave like model proteins. Therefore, glycosylated proteins were analyzed to comparatively investigate the influence of glycosylation on Mr determination in the different instruments. In some cases, high deviations were found both among the methods and with regard to reference values. This article provides possible explanations for these findings.
The development of capillary electrophoresis, especially CE‐SDS devices, has led CE‐SDS to become an established tool in a wide range of applications in the analysis of biopharmaceuticals and is ...increasingly replacing its method of origin, SDS‐PAGE. The goal of this study was to evaluate the comparability of molecular weight (MW) determination especially by CE‐SDS and SDS‐PAGE. For ensuring comparability, model proteins that have little or no posttranslational modifications and an IgG antibody were used. Only a minor influence of sample preparation conditions, including sample buffer, temperature conditions, and different reducing agents on the MW determination were found. In contrast, the selection of the MW marker plays a decisive role in determining the accurate apparent MW of a protein. When using different MW markers, the deviation in MW determination can exceed 10%. Interestingly, CE‐SDS and 10% SDS‐PAGE hardly differ in their trueness of MW determination. The trueness in relation to the reference MW for each protein was calculated. Although the trueness values for the model proteins considered range between 1.00 and 1.11 using CE‐SDS, they range between 0.93 and 1.03 on SDS‐PAGE, depending on the experimental conditions chosen.
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•A recyclable magnetic SDS-coated Fe3O4 promoter was designed and synthesized.•The promotional effect of bare Fe3O4 and SDS-coated Fe3O4 on hydrate formation was studied.•Comparison ...of cycle performance between bare Fe3O4 and SDS-coated Fe3O4 was conducted.•The mechanism of promotion during the cycle experiments with SDS-coated Fe3O4 was researched.
Gas hydrate has been proposed as an effective medium for gas separation, desalination, gas storage and so on, yet the low reaction rate has been hindering the industrialization of hydrate-based technology. Hence various kinds of promoters, especially nano particles, have been introduced and investigated to increase the rate of hydrate formation. However, the recyclability of these promoters has not been given sufficient attention from an environmental friendly and economic point of view. In this study, a recyclable magnetic Fe3O4 nanoparticle coated with SDS (SDS-coated Fe3O4) was synthesized and successfully used for hydrate formation promotion as well as cycle experiments. The results showed that SDS-coated Fe3O4 exhibited more efficient promotion for hydrate formation than bare Fe3O4 in the studied concentration range. Especially, the induction time and reaction time can be significantly reduced to 77.6 ± 24.1 and 36 ± 3 min, respectively, and the methane storage capacity can be maintained up to 130 ± 5.9 v/v with the concentration of 20 g/L SDS-coated Fe3O4. Further comparison of bare Fe3O4 and SDS-coated Fe3O4 during cycle experiments showed that after 5 cycles, the methane storage capacity and reaction time in presence of SDS-coated Fe3O4 can still be maintained as 119.5 ± 8 v/v and 110 ± 10 min, which were even better than the performance of bare Fe3O4 just after two cycles. To sum up, SDS-coated Fe3O4 can be recycled and reused many times for the hydrate formation, indicating that the SDS-coated Fe3O4 has a potential to increase the recyclability and its economy for promoters in the hydrate-based technology.
Four strains (SB-PR, SB-RS, SB-RD, and SB-RM) of Trypanosoma evansi (T. evansi) were used in this study. SB-PR is known to be trypanocide-sensitive, while the others are trypanocide-resistant to ...suramin, diminazene diaceturate, and melarsomine hydrochloride, respectively. SB-RS, SB-RD, and SB-RM are derivatives of a single field isolate of SB-PR. Trypanocide resistance will not only increase costs and decrease production efficiency but will also affect effective treatment strategies. Therefore, studies on this topic are important to avoid inefficient production and ineffective treatment. This paper aims to presents a comparative molecular characterization of the trypanocide-resistant strains compared to the parent population. Comparative molecular characterization of these strains based on a protein profile analysis performed with sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), DNA fingerprinting of random amplified polymorphic DNA (RAPD), and the molecular characterization of expression-site-associated 6 (ESAG6), variant surface glycoprotein (VSG), and T. evansi adenosine transporter-1 (TevAT1) gene sequences. The results show three derived strains (SB-RS, SB-RD, and SB-RM) exhibit different banding patterns than SB-PR. According to the RAPD results, SB-RS and SB-RD are different strains with DNA fingerprint similarities of about 77.8 %, while the DNA fingerprint of SB-RM has a similarity of 44.4 % to SB-RS and SB-RD. No differences in VSG were found among the four strains; however, ESAG6 showed differences in both nucleotide and amino acid sequences, as well as in its secondary and 3D structure. In conclusion, all molecular analyses of the ESAG6 gene showed that SB-PR, SB-RS, SB-RD, and SB-RM are different strains. Furthermore, SB-PR, SB-RS, SB-RD, and SB-RM did not exhibit the TevAT1 gene, so the resistance mechanism was determined to be unrelated to that gene.
•Resistance to some anti-trypanosoma drugs occurs in Trypanosoma evansi species.•Resistance can occur in strains that form separate subpopulations of their parent isolates.•Molecular characterization among resistant subpopulations can be distinguished from their parent populations by a variety of approaches.•Resistance marker genes such as T. evansi adenosine transporter-1 (TevAT1) may not always be reliable.•The transferrin receptor-encoding gene in Trypanosoma evansi may be used in molecular characterization to distinguish between resistant subpopulations and their original parents.
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•The synergistic effect of SDS/δ-FeOOH and H2O2 enhanced the removal of Tl.•The removal capacity of Tl and U from wastewater was as high as 182.9 and 359.6 mg/g, respectively.•The ...adsorption data of Tl and U are well consistent with the Freundlich isotherm model.•Precipitation, ion exchange, and surface oxidation and complexation contributed to the removal of Tl(III) and U(VI).•SDS/δ-FeOOH can function appropriately in seriously contaminated media.
Thallium (Tl) and uranium (U) contaminants pose serious threats to the ecological environment and human health. In this research, a cost-effective feroxyhite (δ-FeOOH) dispersed with sodium dodecyl sulfonate (SDS) was prepared and a series of experiments were optimized to explore the removal mechanism of Tl+ and UO22+ from the effluent. The SDS/δ-FeOOH exhibited highly dispersed colloidal particles and showed significantly enhanced adsorption performance on the removal of Tl and U in the presence of H2O2 and pH of 7.0. Equilibrium uptakes of 99.5% and 99.7% were rapidly achieved for Tl+ and UO22+ within 10 min, respectively. The Freundlich isotherm model fitted well with the adsorption data of Tl and U. The maximum isotherm sorption capacity of SDS/δ-FeOOH for Tl+ and UO22+ was 182.9 and 359.6 mg/g, respectively. The sorption of Tl followed the pseudo-second-order kinetic model, whereas the sorption of U followed the pseudo-first-order kinetic model. The uptake of Tl and U by SDS/δ-FeOOH was notably inhibited at Na+, K+ concentrations over 5.0 mM, and a high content of dissolved organic matter (over 0.5 mg/L). The mechanistic study revealed that ion exchange, precipitation, and surface complexation were main mechanisms for the removal of Tl and U. The findings of this study indicate that stabilizer dispersion may serve as an effective strategy to facilitate the treatment of wastewater containing Tl and U by using δ-FeOOH.
To prevent Maillard browning of the Japanese common squid Todarodes pacificus during air-drying, the effect of treatment with a saturated sodium citrate (Na-citrate) solution was investigated. The ...degree of browning of dried squid meat immersed in the Na-citrate solution before drying (Na-citrate meat) was significantly lower than that of dried untreated meat and the dried meat immersed in ion exchanged water before drying. Results of SDS-PAGE analysis revealed that myosin heavy chain degradation of the Na-citrate meat was suppressed during drying compared to other dried samples. The total amount of free amino acids in the Na-citrate meat was lower than that in the other dried samples. These results suggest that Na-citrate prevents the generation of free amino acids, which are involved in the Maillard reaction, and results in a lower degree of brown discoloration of dried squid.
In the present study, a six-directional sampling method (SDSM) and six-directional sampling mean mixing indices (SDS-mMI) i.e., SDS-mLMI, SDS-mRSD, and SDS-mSMI based on SDSM are proposed for the ...first time by considering Lacey mixing index (LMI), relative standard deviation (RSD) and sub-domain mixing index (SMI) as basis to assess the solids blending performance in DEM simulations. The proposed approach consists of dividing the blender into small grids, and accumulating the mass and mass contributions of each type of particle by moving in six different directions to generate predetermined number of samples, finding the mixing index in each direction, and finding the mean value of the index over all the six directions. The proposed approach is evaluated for two typical blenders with cohesive/cohesion-less, mono/bi-dispersed particles systems. The proposed mixing indices based on the sampling approach are compared with the same mixing indices based on BCSM, and also with other non-sampling indices.
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•Six-directional sampling method (SDSM) & mean mixing indices (SDS-mMI) are proposed.•SDSM applied and SDS-mMI computed for 50 L industrial bin-blender &14 L tote blender.•Cohesive & cohesion-less, mono & bi-dispersed particles considered as test cases.•SDS-mMI performance compared with BCSM, sub-domain, and non-sampling mixing indices.•Proposed SDSM based SDS-mRSD validated through experimental results from literature.
Pea and rice proteins are promising to substitute allergenic proteins, and increasingly, play important roles in the food industry because of their hypoallergenic characteristics and nutritional ...value. However, manufacturers generally provide limited functionality information on these proteins. Therefore, this study comprehensively compared functional properties of wheat, soybean, rice, and pea proteins for their industrial applications and illustrated correlation among various functionalities. Results showed that protein solubility (PS) was highly related to its water absorption (WA) capacity, emulsifying activity index (EAI), and emulsion stability index (ESI). The overall functionality of pea protein was close to that of soybean protein while rice protein cannot match with all other proteins. sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS‐PAGE) analysis indicated the composition of each protein was unique. While the deconvolution of the amide I band of the Raman spectra indicated soybean and pea proteins that shared similar features, but they were different from that of wheat and rice proteins.
Practical applications
Due to the allergenicity of wheat and soybean proteins, food manufacturers are looking for alternative protein sources. Rice and Pea proteins are promising substitutes because of their “allergen‐friendly” as well as their emergence in the food market. This study provided a comprehensive comparison of the functionality of commercially available wheat, soybean, rice, and pea proteins. The information presented in this study would be helpful to food scientists, scholars, or engineers when they develop appropriate application of various proteins in food products.
Functional properties of wheat, soybean, rice, & pea proteins were strictly compared.
Pea protein is close to soybean protein while rice protein cannot match with others.
Protein solubility was highly associated with water absorption capacity, EAI & ESI.
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•Catanionic niosomes, composed of cationic and anionic surfactants, are multifunctional carriers for anticancer drugs.•CTAB and SDS were utilized as positively and negatively charged ...surfactants, respectively.•The behavior of Cabozantinib, an FDA-approved c-Met inhibitor, as the drug sample, was studied in the bilayer.•The influence of cationic/anionic molar ratios on the bilayer features was investigated.
Niosomes are adaptable nanocarriers for the delivery and controlled release of anticancer drugs. The addition of ionic surfactants could easily functionalize these carriers. Catanionic niosomes that are comprised of cationic and anionic surfactants are effective drug-delivery vehicles. Here, we aim to evaluate the impact of the cationic/anionic ratio on the noisome characteristics.
A novel approach utilizing molecular modeling was utilized to analyze some characteristics of catanionic niosomes, showing great potential as a vehicle for anticancer drugs. The nonionic surfactant SPAN60, along with cholesterol as the stabilizer, was utilized in the study. Moreover, CTAB and SDS were used as positively and negatively charged surfactants, respectively. An FDA-approved c-Met inhibitor, cabozantinib, was selected as the drug. Several significant parameters associated with the cabozantinib molecule and its properties within the bilayer like hydrogen bonding, total energy, radius of gyration (Rgyr), diffusion coefficient, and radial distribution function (RDF).
The findings suggest that the cabozantinib’s hydrogen bonding plays a vital role in the drug’s movement through the bilayer. The CTAB-rich niosomes showed a higher number of hydrogen bonds compared to the SDS-rich formulations. The diffusion coefficient was in agreement with the number of H-bonding, and this value increased from 3.12 × 10-12 (m2/s) in CTAB-rich niosome to 7.66 × 10-12 (m2/s) in SDS-rich niosime.
The total binding energy between the drug and bilayer components can control drug release. The computational approach could sufficiently describe the influence of cationic/anionic molar ratios on the bilayer features, and the characteristics of catanionic niosomes could be easily adjusted for the controlled release of anticancer drugs.
In recent years, the number of active pharmaceutical ingredients with high therapeutic impact, but very low water solubility, has increased significantly. Thus, a great challenge for pharmaceutical ...technology is to create new formulations and efficient drug-delivery systems to overcome these dissolution problems.
Drug formulation in solid dispersions (SDs) is one of the most commonly used techniques for the dissolution rate enhancement of poorly water-soluble drugs. Generally, SDs can be defined as a dispersion of active ingredients in molecular, amorphous and/or microcrystalline forms into an inert carrier. This review covers literature which states that the dissolution enhancement of SDs is based on the fact that drugs in the nanoscale range, or in amorphous phase, dissolve faster and to a greater extent than micronized drug particles. This is in accordance to the Noyes-Whitney equation, while the wetting properties of the used polymer may also play an important role.
The main factors why SD-based pharmaceutical products on the market are steadily increasing over the last few years are: the recent progress in various methods used for the preparation of SDs, the effect of evolved interactions in physical state of the drug and formulation stability during storage, the characterization of the physical state of the drug and the mechanism of dissolution rate enhancement.
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