Electrophoresis

Analysis of short tandem repeats (STRs) is a global standard method for human identification. Insertion/Deletion polymorphisms (DIPs) can be used for biogeographical ancestry inference. Current DNA typing involves a trained forensic worker operating several specialized instruments in a controlled laboratory environment, which takes 6-8 h. We developed the Quick TargSeq 1.0 integrated system (hereinafter abbreviated to Quick TargSeq) for automated generation of STR and DIP profiles from buccal swab samples and blood stains...

Product-related fragments in monoclonal antibodies (mAbs) can have a significant impact on the efficacy and safety of the product. Capillary electrophoresis sodium dodecyl sulfate (CE-SDS) is a commonly used method for fragment quantification, but it has challenges in peak identification due to the inability to enrich components and the incompatibility of SDS with mass spectrometry (MS). This article presents a workflow for identifying peaks in CE-SDS analysis. The workflow involves comparing the migration time of peaks with that of standards and utilizing MS analysis to identify fragments...

When hospitalized, infants, particularly preterm, are often subjected to multiple painful needle procedures to collect sufficient blood for metabolic screening or diagnostic purposes using standard clinical tests. For example, at least 100 µL of whole blood is required to perform one creatinine plasma measurement with enzymatic colorimetric assays. As capillary electrophoresis-mass spectrometry (CE-MS) utilizing a sheathless porous tip interface only requires limited amounts of sample for in-depth metabolic profiling studies, the aim of this work was to assess the utility of this method for the determination of creatinine in low amounts of plasma using residual blood samples from adults and infants...

Imazamox (IMX), a chiral herbicide used in cereals and oilseed crops to control weeds, is commonly sold as a racemic mixture. Its enantiomers, being chiral compounds, may exhibit unique properties when exposed to chiral environments. While IMX enantiomers have been reported to degrade differently in soil and be toxic to some species, their effects on human systems remain poorly understood. This study utilized Caco-2 (human colon adenocarcinoma cell line) cells to assess the in vitro permeability of a racemic mixture of IMX and its isolated enantiomers...

The negative template control or negative amplification control has been an essential component of the forensic DNA analysis workflow that helps monitor contamination. As such, the inclusion of a negative control in forensic DNA analysis has been a requirement for all laboratories audited under the FBI's Quality Assurance Standards. As massively parallel sequencing (MPS) becomes more conventional in forensic laboratories, considerations for the inclusion of a negative control in every sequencing run can be evaluated...

To explore the optoelectronic wetting droplet transport mechanism, a transient numerical model of optoelectrowetting (OEW) under the coupling of flow and electric fields is established. The study investigates the impact of externally applied voltage, dielectric constant of the dielectric layer, and interfacial tension between the two phases on the dynamic behavior of droplets during transport. The proposed model employs an improved Young's equation to calculate the instantaneous voltage and contact angle of the droplet on the dielectric layer...

A novel optical-induced dielectrophoresis (ODEP) method employing a pressure-driven flow for the continuous separation of microparticles is presented in this study. By applying alternate current electric field on conductive indium tin oxide substrate and projecting the light geometry into the photoconductive layer, an inhomogeneous electric field is locally induced. The particles experience the dielectrophoretic force when passing through the lighting area, where the strongest electrical field gradient exists...

Biological material is routinely collected at crime scenes and from exhibits and is a key type of evidence during criminal investigations. Improvements in DNA technologies allow collection and profiling of trace samples, comprised of few cells, significantly expanding the types of exhibits targeted for DNA analysis to include touched surfaces. However, success rates from trace and touch DNA samples tend to be poorer compared to other biological materials such as blood. Simultaneously, there have been recent advances in the utility of environmental DNA collection (eDNA) in identification and tracking of different biological organisms and species from bacteria to naked mole rats in different environments, including, soil, ice, snow, air and aquatic...

Biological material is routinely collected at crime scenes and from exhibits and is a key type of evidence during criminal investigations. Touch or trace DNA samples from surfaces and objects deemed to have been contacted are frequently collected. However, a person of interest may not leave any traces on contacted surfaces, for example, if wearing gloves. A novel means of sampling human DNA from air offers additional avenues for DNA collection. In the present study, we report on the results of a pilot study into the prevalence and persistence of human DNA in the air...

The work describes the use of SYBR Gold to improve the detection sensitivity of plasmid DNA topoisomers by capillary gel electrophoresis with laser induced fluorescence in an uncoated capillary. The impact of different dyes, including ethidium bromide, SYBR Green and SYBR Gold, was compared based on detection and separation of DNA plasmid topoisomers. Use of SYBR Gold enabled improvement of detection sensitivity by 15-fold while maintaining good separation resolution of the different topoisomers. The baseline dropped with the use SYBR Gold but was overcome by the employment of a capillary with longer ineffective length (40 vs...

In the context of forensic casework, it is imperative to both establish a DNA profile from biological specimens and accurately identify the specific bodily fluid source. To achieve this, DNA methylation markers have been developed for the differentiation of blood, semen, vaginal epithelial secretions, and saliva samples. Saliva, alternatively referred to as oral fluid, is recognized for its heterogeneous cellular composition, characterized by a mixture of epithelial, leukocytic, and bacterial cells. Consequently, our research has revealed variations in methylation percentages that correlate with the method employed for collecting saliva samples...

A serious error exists in the paper: Alharbi KAM, Riaz A, Sikandar S. An entropy model for Carreau nanofluid ciliary flow with electroosmosis and thermal radiations: a numerical study. Electrophoresis. 2024;45:https://doi.org/10.1002/elps.202300081.

The size variant, which can be measured by capillary electrophoresis sodium dodecyl sulfate (CE-SDS), is a critical quality attribute of monoclonal antibodies (mAbs). The CE-SDS size heterogeneity can hardly be identified by tandem mass spectrometry, which is an intractable obstacle of mAb development and quality control across the industry. We analyzed the purity of an anti-vascular endothelial growth factor receptor 2 (VEGFR-2) mAb, an antagonist of the human VEGFR-2, through reduced CE-SDS and observed glycosylated heavy chain heterogeneity...

Nanopore sequencing technology has broad application prospects in forensic medicine due to its small size, portability, fast speed, real-time result analysis capabilities, single-molecule sequencing abilities, and simple operation. Here, we demonstrate for the first time that nanopore sequencing platforms can be used to identify individuals in the field. Through scientific and reasonable design, a nanopore MinION MK1B device and other auxiliary devices are integrated into a portable detection box conducive to individual identification at the accident site...

Understanding electrokinetic transport in nanochannels and nanopores is essential for emerging biological and electrochemical applications. The viscoelectric effect is an important mechanism implicated in the increase of local viscosity due to the polarization of a solvent under a strong electric field. However, most analyses of the viscoelectric effect have been limited to numerical analyses. In this work, we present a set of analytical solutions applicable to the physical description of viscoelectric effects in nanochannel electrokinetic systems...

Most biological fluids (such as blood, saliva, and lymph) in nature have certain viscoelasticity and are beginning to be used as the carrying fluids for viscoelastic microfluidics. However, the particle-focusing mechanisms in these new biological viscoelastic fluids are still unclear. In this work, the particle-focusing mechanisms in λ-DNA solutions were systematically explored. We first explored the particle focusing dynamics in a square cross-section under varied flow rates to uncover the effects of flow rate on particle focusing...

Cationic surfactant coatings (e.g., CTAB) are commonly used in CE to control EOF and thereby improve separation efficiencies. However, our understanding of surfactant adsorption and desorption dynamics under EOF conditions is limited. Here, we apply automated zeta potential analysis to study the adsorption and desorption kinetics of CTAB in a capillary under different transport conditions: diameter, length, voltage alternation pattern and frequency, and applied pressure. In contrast to other studies, we observe slower kinetics at distinct capillary wall zeta potential ranges...

This study aimed to characterize interactions within colloidal silica particles in their concentrated suspensions, using rheo-confocal measurements and imaging, followed by image analysis. We studied the effect of shear rate (0-500 s-1 ) and solution pH (6, 10) on the dispersion degree of colloidal silica particles via the determination and comparison of interparticle distances and their modeling. Images corresponding to different shear rates were analyzed to identify the coordinates of the particles. These coordinates were further analyzed to calculate the distance among the particles and then their surface-to-surface distance normalized by the particle diameter (H/D)...

Determining the burial time of skeletal remains is one of the most important issues of forensic medicine. We speculated that the microbiome of gravesoil may be a promising method to infer burial time by virtue of time-dependent. As we know, forensic scientists have established various models to predict the postmortem interval of a decedent based on the changes in body and soil microbiome communities. However, limited data are available on the burial time prediction for bones, especially dismembered bones. In this exploratory study, we initially conducted 16S rRNA amplicon high-throughput sequencing on the burial soil of 10 porcine femurs within a 120-day period and analyzed the changes in soil microbial communities...

Oligomerization is an important feature of proteins, which gives a defined quaternary structure to complete the biological functions. Although frequently observed in membrane proteins, characterizing the oligomerization state remains complicated and time-consuming. In this study, 0.05% (w/v) sarkosyl-polyacrylamide gel electrophoresis (05SAR-PAGE) was used to identify the oligomer states of the membrane proteins CpxA, EnvZ, and Ma-Mscl with high sensitivity. Furthermore, two-dimensional electrophoresis (05SAR/sodium dodecyl sulfate-PAGE) combined with western blotting and liquid chromatography-tandem mass spectrometry was successfully applied to study the complex of CpxA/OmpA in cell lysate...