Electrophoresis

The genetic identification of skeletal remains from Chinese People's Volunteers (CPVs) of the Korean War has been challenging because of the degraded DNA samples and the lack of living close relatives. This study established a workflow for identifying CPVs by combining Y-chromosome short tandem repeats (Y-STRs), mitochondrial DNA (mtDNA) hypervariable regions I and II, autosomal STRs (aSTRs), and identity-informative SNPs (iiSNPs). A total of 20 skeletal remains of CPVs and 46 samples from their alleged relatives were collected...

Multiplex PCR is a critical step when preparing amplicon library for next-generation sequencing. However, there are several challenges related to multiplex PCR including poor uniformity, nonspecific amplification, and primer-dimers. To address these issues, we propose a novel solution strategy that involves using a low cycle number (<10 cycles) in multiplex PCR and then employing carrier DNAs and magnetic beads for the selection of targeted products. This technique improves the amplicon uniformity while also reducing primer-dimers and PCR artifacts...

Chemically active droplets display complex self-propulsion behavior in homogeneous surfactant solutions, often influenced by the interplay between diffusiophoresis and Marangoni effects. Previous studies have primarily considered these effects separately or assumed axisymmetric motion. To understand the full hydrodynamics, we investigate the motion of a two-dimensional active droplet under their combined influences using weakly nonlinear analysis and numerical simulations. The impact of two key factors, the Péclet number ( <mml:math xmlns:mml="https://www...

Methamphetamine (MA) is a highly addictive mental stimulant, and MA abuse remains a significant public health problem worldwide, while effective treatment options are limited. Lycium barbarum polysaccharide (LBP), a major effective component extracted from Lycium barbarum, has potential health-promoting effects on the nervous system; however, its role in MA dependence remains unclear. In this study, the conditioned place preference (CPP) of MA addiction in adult male mice was established to detect changes in gut microbiota profiles after LBP treatment through 16S rRNA gene sequencing...

The analysis of cell electrophysiology for pathogenic samples at BSL3 can be problematic. It is virtually impossible to isolate infected from uninfected without a label, for example green fluorescent protein, which can potentially alter the cell electrical properties. Furthermore, the measurement of highly pathogenic organisms often requires equipment dedicated only for use with these organisms due to safety considerations. To address this, we have used dielectrophoresis to study the electrical properties of the human THP-1 cell line and monocyte-derived macrophages before and after infection with non-labelled Mycobacterium tuberculosis...

Tween 20 is frequently added to particle suspensions for reducing the particle-wall adhesion and particle-particle aggregation in microfluidic devices. However, the influences of Tween 20 on the fluid and particle behaviors have been largely ignored. We present in this work the first experimental study of the effects of Tween 20 addition on the electrokinetic transport of fluids and particles in a polydimethylsiloxane microchannel. We find that adding 0.1% v/v Tween 20 to a buffer solution can significantly reduce the electroosmotic mobility as well as the electrokinetic and electrophoretic mobilities of polystyrene particles and yeast cells...

Numerical modeling of Taylor dispersion analysis (TDA) was performed using COMSOL Multiphysics to facilitate better and faster optimization of the experimental conditions. Parameters, such as pressure, electric field, diameter, and length of capillary on the TDA conditions, were examined for particles with hydrodynamic radius (Rh ) of 2.5-250 Å. The simulations were conducted using 25, 50, and 100 cm length tubes with diameters of 25, 50, and 100 µm. It was shown that particles with larger diffusion coefficients gave more accurate results at higher velocities, and in longer and wider columns; particles with smaller diffusion coefficients gave more accurate results at smaller velocities, and in shorter and thinner columns...

Targeted bisulfite sequencing using single-base extension (SBE) can be used to measure DNA methylation via capillary electrophoresis on genetic analyzers in forensic labs. Several accurate age prediction models have been reported using this method. However, using different genetic analyzers with different software settings can generate different methylation values, leading to significant errors in age prediction. To address this issue, the study proposes and compares four methods as follows: (1) adjusting methylation values using numerous actual body fluid DNA samples, (2) adjusting methylation values using control DNAs with varying methylation ratios, (3) constructing new age prediction models for each genetic analyzer type, and (4) constructing new age prediction models that could be applied to all types of genetic analyzers...

Recombinant adeno-associated virus (rAAV) is the leading platform of gene delivery for its long-lasting gene transformation and low immunogenicity. Characterization of the integrity and purity of the rAAV genome is critical to ensure clinical potency and safety. However, current rAAV genome characterization methods that can provide size assessment are either time-consuming or not easily accessible to general labs. Additionally, there is a lack of right reference standard for analyzing long single-stranded DNA (ssDNA) fragments...

In this paper, the development and application of a multiple heart-cutting achiral-chiral LC-LC method (mLC-LC) for the analysis of dansylated (Dns) branched-chain amino acids in commercial tablets are described. In the first dimension, a Waters Xbridge RP C18 achiral column was used under gradient conditions with buffered aqueous solution and acetonitrile. The elution order Dns-valine (Dns-Val) < Dns-isoleucine (Dns-Ile) < Dns-leucine (Dns-Leu) turned out with full resolution between adjacent peaks: 7...

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...