Stability of volcanic nanoparticles using combined capillary zone electrophoresis and laser diffraction

Application and optimization of capillary zone electrophoresis in vitamin analysis

Application of capillary zone electrophoresis to the analysis and to a stability study of cephalosporins

Metallothioneins (MTs) from various eukaryotic species were subjected to capillary zone electrophoresis (CZE) performed under the following conditions: Capillary: untreated polyimide-clad fused silica 75 (im I.D. × 94 cm; Loading and Running Voltage: 30 kV; Electrode Buffer: 50 mM Tris-HCI pH 9.1; Sample Buffer: 10 mM Tris-HCI pH 9.1; Sample Volume: 250 μl; Detection: UV absorbance at 214 nm; Loading Method: electrokinetic migration; Loading Times: 1–6 seconds. Complete separation of MT-1 and MT-2 isoforms was achieved in less than 6 min. Using a rabbit liver Cd, Zn-MT standard (0.5 mg/ml), a linear relationship was found to exist between the voltage used to load the MT sample and the integrated peak area of the individual MT isoforms. Similarly, the integrated peak area of the separated MT isoforms was a linear function of the time used to load the sample. These findings suggest that with appropriate standardization CZE is capable of both qualitative and quantitative determinations of MT isoforms. In CZE, the concentration of MT in solution determines the limit of sensitivity. MT could be accurately detected at a concentration as low as 10 μg/ml. CZE was applied to assess thermal and proteolytic degradation of rabbit liver MT. CZE represents a rapid analytical technique for the characterization of MT isoforms that requires very little sample yet provides excellent resolution of individual MT isoforms.

Determination of deamidated isoforms of human insulin using capillary electrophoresis.

The application of capillary zone electrophoresis (CZE) to the separation and determination of creatinine in human urine with photodiode array detection was described. Optimum conditions for the separation were established. The effect of pH of the background buffer on the existence state of creatinine was investigated. Photodiode array detection permitted the rapid identification of creatinine in the samples analysed. By selecting 234 nm as monitoring wavelength, the interference from urea in urine was eliminated. By selecting a suitable pH, the interferences from other substances in urine were also eliminated. The linear range, detection limit, precision and recovery of the method were investigated.

The possibilities and applications of capillary electrophoresis (CE) as an analytical technique for plant secondary metabolites are reviewed. Applications of both capillary zone electrophoresis and micellar electrokinetic capillary chromatography for this purpose are described. CE is compared with high pressure liquid chromato‐graphy (HPLC) as an analytical technique, and the advantages and criticisms of CE are described. The effects of the applied voltage, capillary temperature, electrolyte concentration and nature (complexing or non‐complexing buffers), buffer pH, micelle concentration and nature (sodium dodecyl sulphate or cetyltrimethylammonium bromide and the addition of organic modifiers to the running buffer (organic solvents, cyclodextrins, urea, cholate) on the parameters of separation and resolution of different secondary metabolites are discussed. The applications of CE to the analysis of flavonoid aglycones and glycosides, phenolic acids, quinones, coumarins, alkaloids, capsacinoids, glucosinolates, polyamines, monoterpenes, diterpenes, phytoecdysteroids, cardiac glycosides and saponins are shown. It is concluded that CE is a very promising analytical technique in the analysis of plant secondary metabolites, and it will become an indispensable tool, together with HPLC and gas liquid chromatography, in phytochemical laboratories since these techniques are in many ways complementary, and problems that are difficult to solve by HPLC can often be solved using CE.

Applicability of capillary zone electrophoresis to study metal complexation in solution

12 CE in impurity profiling of drugs

Application of capillary zone electrophoresis in the separation and determination of the curcuminoids in urine

Background and aim Water pollution has become a global environmental problem, especially due to rise in toxicity of heavy metals even at low concentrations. Contaminated drinking water poses a significant threat to public health and this investigation was carried out on the Holy Kali Bein River in Punjab, India, to evaluate the contamination of potentially toxic elements (PTEs) in surface water. This study describes the health risk of potentially toxic elements (PTEs) in the surface water of the River Holy Kali Bein by measuring the concentrations of 10 PTEs, applying correlation and principal component analysis to identify pollution sources, and evaluating carcinogenic and non-carcinogenic risks through chronic daily intake (CDI), and hazard quotient (HQ). Key findings The results showed that only 4 PTEs, such as chromium (Cr) BDL-0.157 mg/L, iron (Fe), 0.485–1.563 mg/L, manganese (Mn) BDL-0.264 mg/L and zinc (Zn) 0.218–0.744 mg/L were detected from water samples. Egenvalues 2.33 (PC1) and 1.05 (PC2) were extracted accounting for 82.57% of the total variance. Results showed the highest CDI value of 0.120 mg/kg-day for iron and HQ value of 0.1911 for Cr via dermal pathway in children indicating that residential receptors may be at risk for non-cancer from these elements. Conclusions Overall, the findings demonstrate that continuous exposure to heavy metals in rivulet Holy Kali Bein may pose significant health threats to local communities. This study will encourage the appropriate authorities and policymakers to recognize the areas that pose the most risk and to take professional measures to protect both human health and the ecosystem as a whole.

Machine vision based particle size and size distribution determination of airborne dust particles of wood and bark pellets

Application of capillary and free-flow zone electrophoresis and isotachophoresis to the analysis and preparation of the synthetic tetrapeptide fragment of growth hormone-releasing peptide.

Particle size analysis is most fundamental analysis to powder technology. However, the validation or calibration of particle size analysis, especially the laser diffraction (LD) method, was not often carried out due to the difficulty to prepare the well-known sample. For example, the validation of LD method need spherical reference particles, of which size distribution is better to have a range over one decade of size. As this request, the Association of Powder Process Industry and Engineering, Japan distributed three kinds of standard reference particles (SRP) of spherical barium titanate glass; their size ranges are 1 – 10 µm, 3 – 30 µm and 10 – 100 µm. Those particles are also fitted to the reference particles in JIS Z 8900-1 Standard.In this paper, the particle size distribution (PSD) based on volume of SRP which was converted from the number-based PSD of SRP measured by a scanning electron microscope (SEM) was compared with PSD measured by LD instruments, which was conducted by the Technical Group of Measurement and Control in APPIE. PSD results measured by LD instruments were almost same as each other. PSD by LD method was slightly different from PSD measured by SEM. This discrepancy was discussed by using by a flow type image analysis method which could measure the size of particles in the aqueous solution. It was found that sample particles could not be dispersed completely in the aqueous solution even if using dispersing instruments such as an ultrasonic bath, and that this influence was not serious to the PSD result when using the suitable operating condition of ultrasonic bath.

Determination of illicit and/or abused drugs and compounds of forensic interest in biosamples by capillary electrophoretic/electrokinetic methods

Therapeutic monoclonal antibodies play an important role in biopharmaceuticals, and gradually become one of the main directions of the development of biological medicine. The quality control of monoclonal antibodies has also become the focus of global biopharma companies and regulatory agencies. Capillary electrophoresis has become an important tool in the analysis of monoclonal antibodies with multi-modes and high resolution. In this paper, we reviewed the application of capillary gel electrophoresis, capillary isoelectric focusing and capillary zone electrophoresis on the analysis of purity, isoelectric point/charge heterogeneity and N-glycan profiling of therapeutic monoclonal antibodies.