Combining Direct PCR Technology and Capillary Electrophoresis for an Easy-to-Operate and Highly Sensitive Infectious Disease Detection System for Shrimp

Infectious diseases are considered the greatest threat to the modern high-density shrimp aquaculture industry. Specificity, rapidity, and sensitivity of molecular diagnostic methods for the detection of asymptomatic infected shrimp allows preventive measures to be taken before disease outbreaks. Routine molecular detection of pathogens in infected shrimp can be made easier with the use of a direct polymerase chain reaction (PCR). In this study, four direct PCR reagent brands were tested, and results showed that the detection signal of direct PCR in hepatopancreatic tissue was more severely affected. In addition, portable capillary electrophoresis was applied to improve sensitivity and specificity, resulting in a pathogen detection limit of 25 copies/PCR-reaction. Juvenile shrimp from five different aquaculture ponds were tested for white spot syndrome virus infection, and the results were consistent with the Organization for Animal Health’s certified standard method. Furthermore, this methodology could be used to examine single post larvae shrimp. The overall detection time was reduced by more than 58.2%. Therefore, the combination of direct PCR and capillary electrophoresis for on-site examination is valuable and has potential as a suitable tool for diagnostic, epidemiological, and pathological studies of shrimp aquaculture.

Study on the Rapid Preparation of Zinc Oxide Nanotubes by Galvanostatic Etching

At present, most of the methods for preparing ZnO nanotubes are chemical etching of ZnO nanorods, which is inefficient and takes a long time. In this paper, ZnO nanotubes were successfully prepared by galvanostatic etching. Nanotubes prepared by galvanostatic etching only took 1/6 of the time of chemical etching. The ZnO nanotubes obtained by two different methods were tested by XRD and SEM. It is found that the crystal structure and crystallinity of the ZnO nanotubes obtained by galvanostatic etching are unchanged, and the internal corrosion of the nanotubes by galvanostatic etching is more thorough and has a larger specific surface area. In the tests of UV-vis spectrophotometry, fluorescence spectra and electrochemical performance test, the optical properties and electrochemical performance of ZnO nanotubes obtained by galvanostatic etching are better than those obtained by chemical etching. Because the ZnO nanotubes obtained by galvanostatic etching have larger specific surface area, better optical properties and better electrochemical performance, they have a greater application prospect in sensors and ultraviolet light detectors.

Recent Advances and Applications of Microfluidic Capillary Electrophoresis: A Comprehensive Review (2017-Mid 2019)

Microfluidic capillary electrophoresis (MCE) is the novel technique resulted from the CE mininaturization as planar separation and analysis device. This review presents and discusses various application fields of this advanced technology published in the period 2017 till mid-2019 in eight different sections including clinical, biological, single cell analysis, environmental, pharmaceuticals, food analysis, forensic and ion analysis. The need for miniaturization of CE and the consequence advantages achieved are also discussed including high-throughput, miniaturized detection, effective separation, portability and the need for micro- or even nano-volume of samples. Comprehensive tables for the MCE applications in the different studied fields are provided. Also, figure comparing the number of the published papers applying MCE in the eight discussed fields within the studied period is included. The future investigation should put into consideration the possibility of replacing conventional CE with the MCE after proper validation. Suitable validation parameters with their suitable accepted ranges should be tailored for analysis methods utilizing such unique technique (MCE).

Gold Nanoparticle Size-Dependent Enhanced Chemiluminescence for Ultra-Sensitive Haptoglobin Biomarker Detection

Bovine mastitis (BM) is a frequent disease in the dairy industry that causes staggering economical losses due to decreased milk production and increased health care costs. Traditionally, BM detection depends on the efficacy and reliability of analytical techniques that measure somatic cell counts (SCC), detect pathogens, and reveal inflammatory status. Herein, we demonstrate the detection of bovine haptoglobin, a well-documented acute phase protein for evaluating BM clinical status, by utilizing hemoglobin-binding capacity within luminol chemiluminescence (CL) system. The resulting haptoglobin–hemoglobin complex reduces the CL signal proportionally to inherent haptoglobin concentrations. Different sizes of cross-linked gold nanoparticles (GNPs) were examined for enhanced CL (eCL) signal amplification, presenting over 30-fold emitted radiation enhancement for optimized size within real milk samples with respect to nanoparticle-free assay. The eCL values were proportionally related to nanoparticle size and content, influenced by SCC and pathogen type (e.g., Escherichia coli and coagulase-negative staphylococci). The optimized bioassay showed a broad linear response (1 pg mL⁻¹–10 µg mL⁻¹) and minute detection limit of 0.19 pg mL⁻¹, while presenting quantitative performance in agreement with commercial ELISA kit. Finally, the resulting optimized eCL concept offers an efficient label-free detection of haptoglobin biomarker, offering means to diagnose the severity of the associated diseases.

Capillary electrophoresis of small ions and molecules in less conventional human body fluid samples: A review

In recent years, advances in sensitive analytical techniques have encouraged the analysis of various compounds in biological fluids. While blood serum, blood plasma and urine still remain the golden standards in clinical, toxicological and forensic science, analyses of other body fluids, such as breast milk, exhaled breath condensate, sweat, saliva, amniotic fluid, cerebrospinal fluid, or capillary blood in form of dried blood spots are becoming more popular. This review article focuses on capillary electrophoresis and microchip electrophoresis of small ions and molecules (e.g. inorganic cations/anions, basic/acidic drugs, small acids/bases, amino acids, peptides and other low molecular weight analytes) in various less conventional human body fluids and hopes to stimulate further interest in the field.

Electrophoresis separation assisted G-quadruplex DNAzyme-based chemiluminescence signal amplification strategy on a microchip platform for highly sensitive detection of microRNA

We have developed an electrophoresis separation assisted G-quadruplex DNAzyme-based chemiluminescence (CL) signal amplification strategy on a microchip platform for the detection of trace microRNA. This strategy exhibits high sensitivity and specificity for detection of target molecules.

Recent advances in CE and microchip-CE in clinical applications: 2014 to mid-2017

CE and microchip CE (ME) are powerful tools for the analysis of a number of different analytes and have been applied to a variety of clinical fields and human samples. This review will present an overview of the most recent applications of these techniques to different areas of clinical medicine during the period of 2014 to mid-2017. CE and ME have been applied to clinical chemistry, drug detection and monitoring, hematology, infectious diseases, oncology, endocrinology, neonatology, nephrology, and genetic screening. Samples examined range from serum, plasma, and urine to lest utilized materials such as tears, cerebral spinal fluid, sweat, saliva, condensed breath, single cells, and biopsy tissue. Examples of clinical applications will be given along with the various detection systems employed.

Analysis of proteins and peptides by electromigration methods in microchips

This review presents the developments and applications of microchip electromigration methods in the separation and analysis of peptides and proteins in the period 2011-mid-2016. The developments in sample preparation and preconcentration, microchannel material, and surface treatment are described. Separations by various microchip electromigration methods (zone electrophoresis in free and sieving media, affinity electrophoresis, isotachophoresis, isoelectric focusing, electrokinetic chromatography, and electrochromatography) are demonstrated. Advances in detection methods are reported and novel applications in the areas of proteomics and peptidomics, quality control of peptide and protein pharmaceuticals, analysis of proteins and peptides in biomatrices, and determination of physicochemical parameters are shown.

Capillary electrophoresis chemiluminescence assay of naphthol isomers in human urine and river water using Ni(IV) complex-luminol system

A capillary electrophoresis method involving online indirect chemiluminescence (CL) detection was used to determine naphthol (NAP) isomers. The method was based on the quenching effect of 1- and 2-NAP on a new CL reaction of luminol with Ni(IV) complex in an alkaline medium. Separation was conducted with a 25.0 mM sodium borate buffer containing 0.8 mmol/L luminol. Under optimized conditions, 1- and 2-NAP were baseline separated and detected in less than 8 min. The limits of detection of 1- and 2-NAP were 3.1 and 2.7 μg/L, respectively (S/N = 3), with a linear range of 4.0-80.0 μg/L (r > 0.995). Analysis of real samples demonstrated that the spiked recoveries were in the range of 89.2-107.5% (n = 3). The proposed method was successfully used to determine 1- and 2-NAP contents in three environmental water samples and 14 human urine samples. No derivatization or tedious pretreatment was required in the analysis. The proposed method is a potential approach for routine tests of naphthol isomers in a facile CE-CL system.

Capillary electrophoresis coupled with in-column fiber-optic laser-induced fluorescence detection for the rapid separation of neodymium

In this study, in-column fiber-optic (ICFO) laser-induced fluorescence (LIF) detection technique is coupled with capillary electrophoresis (CE) for the rapid separation of neodymium for the first time. The effects of buffer concentration, buffer pH, and separation voltage on the CE behaviors, including electrophoretic efficiency and detection sensitivity, are investigated in detail. Under the optimal condition determined in this study (15 mM borate buffer, pH 10.50, separation voltage 24 kV), neodymium could be separated effectively from the neighboring lanthanides (praseodymium and samarium) within several minutes, and the limit of detection for neodymium is estimated to be at the ppt level. The ICFO-LIF-CE system assembled in this study exhibits unique performance characteristics such as low cost and flexibility. Meanwhile, the separation efficiency and detection sensitivity of the assembled CE system are comparable to or somewhat better than those obtained in the previous traditional CE systems, indicating the potential of the assembled CE system for practical applications in the fields of spent nuclear fuel analysis, nuclear waste disposal/treatment, and nuclear forensics.