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Streptavidin is a tetrameric protein with high specificity and affinity for biotin. The interaction between avidin and biotin has become a valuable tool in nanotechnology. In recent years, the site‐specific biotin modification of proteins using biotin ligases, such as BirA, has attracted attention. This study established an in vivo method for achieving the complete biotinylation of target proteins using a single plasmid co‐expressing BirA and its target proteins. Specifically, a biotin‐modified protein was produced in Escherichia coli strain BL21(DE3) using a single plasmid containing genes encoding both BirA and a protein fused to BirA's substrate sequence, Avitag. This approach simplifies the production of biotinylated proteins in E. coli and allows the creation of various biotinylated protein types through gene replacement. Furthermore, the biotin modification rate of the obtained target protein could be evaluated using Native‐PAGE without performing complicated isolation operations of biotinylated proteins. In Native‐PAGE, biotin‐modified proteins and unmodified proteins were confirmed as clearly different bands, and it was possible to easily derive the modification rate from the respective band intensities. [ABSTRACT FROM AUTHOR]

Dental caries is a multifactorial chronic disease resulting from the intricate interplay among acid‐generating bacteria, fermentable carbohydrates, and several host factors such as saliva. Saliva comprises several proteins which could be utilized as biomarkers for caries prevention, diagnosis, and prognosis. Mass spectrometry‐based salivary proteomics approaches, owing to their sensitivity, provide the opportunity to investigate and unveil crucial cariogenic pathogen activity and host indicators and may demonstrate clinically relevant biomarkers to improve caries diagnosis and management. The present review outlines the published literature of human clinical proteomics investigations on caries and extensively elucidates frequently reported salivary proteins as biomarkers. This review also discusses important aspects while designing an experimental proteomics workflow. The protein–protein interactions and the clinical relevance of salivary proteins as biomarkers for caries, together with uninvestigated domains of the discipline are also discussed critically. [ABSTRACT FROM AUTHOR]

Pregnancy has its own protein dynamics, reflecting the hormonal profile. Quantitative and qualitative changes in plasma protein profile may provide useful information about this condition. Any alterations may be a signal heralding clinical or subclinical pathology. The objective of our study was to compare the plasma protein profile between selected months of pregnancy in cows for a better understanding gestation course. For this purpose, we collected blood from healthy pregnant (n = 30; n = 6 for each pregnancy stage) and non‐pregnant (C; n = 6) Holstein‐Friesian cows during a routine veterinary examination. Collected samples were selected according to pregnancy month (first, second, third, sixth, and ninth), prepared, and separated by two‐dimensional electrophoresis. The Delta‐2D program compared and statistically evaluated scanned gel images from the appropriate months. The mean volume of the spots was considered. The MALDI TOF/TOF spectrometer was used to identify statistically significant proteins. There were 11 distinct proteins found, including peptidyl‐prolyl cis‐trans isomerase F, oligoribonuclease, and PRELI domain‐containing protein 3B (all of them have the lowest abundance in the C group), alpha‐1B‐glycoprotein, L‐gulonolactone oxidase, hemopexin (first month with higher abundance than control), alpha‐2‐HS‐glycoprotein (significantly higher abundance in the first month than in remaining groups), ermin (absent in the first month and lower abundance in the third and sixth months than in the remaining groups and control), endophilin‐A2 (significant differences between the control and the second, third, sixth, and ninth months), apolipoprotein A‐I (significant difference between control and the first and sixth months), alpha‐1‐antiproteinase (significant difference between control and the ninth month). The study demonstrated the distinctions between plasma protein composition and alterations during the pregnancy course which may potentially serve as diagnostic tools. [ABSTRACT FROM AUTHOR]

We developed a simple, paper‐based device that enables sensitive detection by mass spectrometry (MS) without solid phase extraction or other sample preparation. Using glass fiber filter papers within a 3D printed holder, the device employs electrokinetic manipulations to stack, separate, and desalt charged molecules on paper prior to spray into the MS. Due to counter‐balanced electroosmotic flow and electrophoresis, charged analytes stack on the paper and desalting occurs in minutes. One end of the paper strip was cut into a sharp point and positioned near the inlet of a MS. The stacked analyte bands move toward the paper tip with the EOF where they are ionized by paper spray. The device was applied to analysis of PFAS in tap water with sub part‐per‐trillion detection limits in less than ten minutes with no sample pretreatment. Analysis of opioids in urine also occurs in minutes. The crucial parameters to enable stacking, separation, and MS ionization of both positively and negatively charged analytes were determined and optimized. Experimental and computational modeling studies confirm the electrokinetic stacking and analyte transport mechanisms. On‐paper separations were carried out by stacking analyte bands at different locations depending on their electrophoretic mobility, achieving baseline separation in some cases. [ABSTRACT FROM AUTHOR]

Background: Upon infection activated plasma cells produce large quantities of antibodies which can lead to the emergence of a monoclonal component (MC), detectable by serum protein electrophoresis (SPEP). This study aims to investigate any correlation between SARS‐CoV‐2 infection and MC development and, if identified, whether it persists during follow‐up. Methods: SPEPs of 786 patients admitted to hospitals between March 01 2020 and March 31 2022 were evaluated. Positive (SARS‐CoV‐2+) and negative (SARS‐CoV‐2−) patients to nasopharyngeal swab for SARS‐CoV‐2 by RT‐PCR were included. The persistence/new occurrence of MC was investigated for all patients during follow‐up. Patient groups were compared by chi‐square analysis. Results: MC was identified in 12% of all patients admitted to hospital, of which 28.7% were SARS‐CoV‐2+. The most common immunoglobulin isotype in both groups was IgG‐k. There was no correlation between MC development and SARS‐CoV‐2 infection (p = 0.173). Furthermore, the risk of MC persistence in SARS‐CoV‐2‐negative patients was revealed to be higher than in the SARS‐CoV‐2+ at follow‐up (HR = 0.591, p = 0.05). Conclusions: Our study suggests that the detection of MC during SARS‐CoV‐2 infection is most likely due to the hyperstimulation of the humoral immune system, as also occurs in other viral infections. [ABSTRACT FROM AUTHOR]

Summary: Foodomics is an emerging probing method of phenotype investigation of the different milk proteins and their subtypes. The polymorphic nature of the β‐casein (β‐Cn) protein has shown fourteen different protein variants to date in bovines. The analysis of the β‐Cn genetic polymorphism from the milk of the crossbred dairy animals is crucial for the quality assurance of the consumers from the various health concerns, especially those linked with the A1 phenotype which yields β‐casomorphin‐7 on in vivo digestion. Jersey‐crossed Indian cattle have been widely utilised in dairy because of their better milk production and survival performance trait. In this investigation, an SDS‐PAGE coupled with a high‐resolution accurate mass spectrometry‐based proteomics approach has been applied to identify the presence of specific phenotype of the β‐Cn protein in the milk of the 24 Indian crossbred (Jersey crossed) animals. Amino acid sequential analysis has been done using different search modules, as MS Amanda and Sequest HT showed 17 cows are producing A2 β‐Cn (Pro~67) while only seven animals yielded the A1 variant (His~67). The maximum number of Indian Jersey‐crossed animals are lactating milk having A2 β‐Cn. The A2 milk from the crossbred animals is free from the negative impact on health caused by β‐casomorphin‐7 (BCM‐7) released during digestion of the A1 phenotype. Among the molecular biology techniques, top‐down proteomics has been an intriguing technique for the identification of protein genetic polymorphic products. [ABSTRACT FROM AUTHOR]

The review provides an overview of recent developments and applications of capillary electromigration (CE) methods for the determination of important physicochemical parameters of various (bio)molecules and (bio)particles. These parameters include actual and limiting (absolute) ionic mobilities, effective electrophoretic mobilities, effective charges, isoelectric points, electrokinetic potentials, hydrodynamic radii, diffusion coefficients, relative molecular masses, acidity (ionization) constants, binding constants and stoichiometry of (bio)molecular complexes, changes of Gibbs free energy, enthalpy and entropy and rate constants of chemical reactions and interactions, retention factors and partition and distribution coefficients. For the determination of these parameters, the following CE methods are employed: zone electrophoresis in a free solution or in sieving media, isotachophoresis, isoelectric focusing, affinity electrophoresis, electrokinetic chromatography, and electrochromatography. In the individual sections, the procedures for the determination of the above parameters by the particular CE methods are described. [ABSTRACT FROM AUTHOR]

Background: Beta‐2 transferrin (B2‐Tf) gel electrophoresis (GE) is the preferred non‐invasive diagnostic modality for confirming cerebrospinal fluid (CSF) in body fluids. While B2‐Tf GE testing is highly sensitive and specific for CSF, false‐positive (FP) and false‐negative (FN) results can lead to diagnostic and therapeutic dilemmas. Several series have demonstrated potential causes of false B2‐Tf GE results, but few studies have reported reasons for these errors. The purpose of this systematic review was to describe sources of B2‐Tf GE errors. Methods: A systematic review was performed by searching OVID, EMBASE, and Web of Science databases for B2‐Tf GE studies. After applying exclusion criteria, original research studies directly addressing erroneous B2‐Tf GE results underwent qualitative analysis. Results: Of the 243 abstracts screened, 71 underwent full‐text review and 18 studies reporting B2‐Tf GE errors were included for analysis. There were 15 potential FPs, 12 actual FPs, 12 potential FNs, 19 actual FNs, and 14 indeterminate results. There were also 246 potentially indeterminate results from in vitro studies. Reasons for B2‐Tf GE errors included serum transferrin alterations (n = 17; all potential), infection related (n = 13; 9 potential), orbital or salivary contamination (n = 2; 1 potential), and collection related (n = 255; 246 potential). There were 31 false or indeterminate results with unspecified reasons. There were no reported errors due to laboratory processing. Conclusions: Multiple potential or actual reasons for false or indeterminate results have been reported for B2‐Tf GE testing of rhinorrhea and otorrhea. Future studies should explore reasons for B2‐Tf testing errors and how these may affect clinical decision making. [ABSTRACT FROM AUTHOR]

Accumulating evidence has demonstrated that high‐risk human papillomaviruses (HR‐HPVs) are involved in the etiology of a subset of oropharyngeal squamous cell carcinoma (OPSCC). In this regard, the International Agency for Research on Cancer (IARC) has recommended direct molecular HPV testing. So far, there is no agreement on the most appropriate method for HPV detection on OPSCC formalin‐fixed paraffin‐embedded (FFPE) materials. In this study, we aimed to evaluate the performance of the high‐sensitive SureX HPV assay in OPSCC FFPE tissues compared with LiPA‐25 and p16ink4a immunostaining. A retrospective series of FFPE primary OPSCC cases were diagnosed between 2008 and 2019 and provided by the Henan Cancer Hospital, China. The level of agreement of two assays was determined using Cohen's Kappa (κ) statistics. A total of 230 FFPE OPSCC samples from tumor resections (n = 160) and diagnostic biopsies (n = 70) were detected. Sixty‐six (28.7%) and 70 (30.4%) samples were identified as HPV‐DNA‐positive by LiPA‐25 and SureX, respectively, of which HPV16 was largely the most common type (95.5% vs 94.3%). We found a perfect concordance between LiPA‐25 and SureX for HPV‐DNA status (κ = 0.906, 95% CI: 0.875–0.937) and for HPV16 (κ = 0.925, 95% CI: 0.897–0.953). In addition, SureX and p16ink4a immunostaining had a perfect concordance (κ = 0.917, 95% CI: 0.888‐0.946). Moreover, the HPV‐driven fraction, based on double positivity for HPV‐DNA and p16ink4a, was similar between SureX (63 of 230, 27.4%) and LiPA‐25 (60 of 230, 26.1%). Similar results were found in samples from resections and biopsies. SureX and LiPA‐25 are comparable. SureX could be used for routine HPV‐DNA detection and genotyping on archival OPSCC FFPE tissues. [ABSTRACT FROM AUTHOR]

Objectives: Periodontitis is an inflammatory disease caused by bacteria present in the dental biofilm. However, the presence of two oral protozoans, Entamoeba gingivalis and Trichomonas tenax, in patients with the periodontal disease remains largely unknown in Taiwan. Therefore, we investigated the prevalence of oral microbial infections between the sites with mild gingivitis and chronic periodontitis in patients. Materials and Methods: We collected 60 dental biofilm samples from sites with mild gingivitis (probing depth <5 mm) and chronic periodontitis (probing depth ≥5 mm) from 30 patients at the National Cheng Kung University Hospital. The samples were analyzed via polymerase chain reaction and gel electrophoresis. Results: Among oral protozoans, E. gingivalis and T. tenax were detected in 44 (74.07%) and 14 (23.33%) of all samples, respectively. Among oral bacteria, Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia were detected in 50 (83.33%), 47 (78.33%), and 48 (80.0%) samples, respectively. Conclusions: This study, which is the first to analyze E. gingivalis and T. tenax presence among patients with periodontitis in Taiwan, revealed an association between periodontitis and oral microbes. [ABSTRACT FROM AUTHOR]

The general expression for the time‐independent electrophoretic velocity of a spherical colloidal particle with a slippage surface in a microstructure electrolyte solution is derived. The two extreme cases of nonconducting and perfect conducting particles are investigated. The derived expression is valid for arbitrary Debye length and low particle zeta potentials. The concept of velocity spin slip is incorporated with the usual velocity slip at the particle's surface. The effect of the microstructure of fluid particles on the electrophoresis phenomena is discussed based on a micropolar fluid model. The influences of velocity slip and velocity spin slip are shown through various plots of electrophoretic velocity. The limiting case of electrolyte viscous solution is recovered. The principal findings of this research can be summarized as follows: As the micropolarity parameter increases, the normalized electrophoretic velocity decreases and reaches its peak in the case of Newtonian fluids. Additionally, the velocity slip acts as a counteracting factor that promotes an increase in the electrophoretic velocity. In the context of nonconducting particles, the normalized electrophoretic velocity rises as the spin slip parameter and Debye length decrease. Conversely, for perfectly conducting particles, it increases as the spin slip parameter and Debye length increase. [ABSTRACT FROM AUTHOR]

Conventional computation techniques face challenges of deviations in Moore's law and the high‐power consumption of data‐centric computation tasks. Neuromorphic engineering attempts to overcome these issues by taking inspiration from neuron assemblies, ranging from distributed synaptic plasticity through orchestration of oscillator‐like action potential toward avalanche dynamics. Although solid networks of nanoparticles (NPs) are proven to replicate fingerprints of criticality and brain‐like dynamics, the aspect of dynamic spatial reconfigurations in the connectivity of networks remains unexplored. In this work, Ag/poly(ethylene glycol) (PEG) nanofluids are demonstrated as potential systems to mimic the spatio‐temporal reconfiguration of network connections. The nanofluids are prepared by directly loading Ag NPs from the gas aggregation cluster source into liquid PEG. The NPs exhibit a negative zeta potential in PEG; if the potential difference is applied between two electrodes submerged in this nanofluid, the NPs migrate toward the anode, accumulate in its vicinity, and form a conductive path. Spikes of electric current passing through the path are detected, accompanied by resistive switching phenomena, similar to the random switching dynamics in solid NPs networks. The unique behavior of Ag/PEG nanofluids makes them promising for the realization of spatio‐temporal reconfigurations in network topologies with the potential to transition to 3D. [ABSTRACT FROM AUTHOR]

The advancement of highly secure and inexpensive aqueous zinc ion energy storage devices is impeded by issues, including dendrite growth, hydrogen evolution and corrosion of zinc anodes. It is essential to modify the interface of zinc anodes that homogenizes ion flux and facilitates highly reversible zinc planarized deposition and stripping. Herein, by coupling zinc ion coordination with acid‐base neutralization under the driving of electrophoresis, manageable mesoscopic phase separation for constructing chitosan frameworks was achieved, thereby fabricating interconnected mesoporous chitosan membranes based heterogeneous quasi‐solid‐state electrolytes integrated with anodes. The framework is constructed by twisted chitosan nanofiber bundles, forming a three‐dimensional continuous spindle‐shaped pore structure. With this framework, the electrolyte provides exceptional ion conductivity of 25.1 mS cm−1, with a puncture resistance strength of 2.3 GPa. In addition, the amino groups of chitosan molecule can make the surface of the framework positively charged. Thus, reversible zinc planarized deposition is successfully induced by the synergistic effect of stress constraint and electrostatic modulation. As a result, as‐assembled zinc ion capacitor has an excellent cycle life and sustains the capacity by over 95 % after 20000 cycles at a current density of 5 A g−1. This research presents a constructive strategy for stable electrolytes‐integrated zinc anodes. [ABSTRACT FROM AUTHOR]

Natural rubber is bio‐based rubber, which plays an important role in carbon neutralization to reduce carbon dioxide emissions. It is widely used in the national economy because of its strain‐induced crystallization properties. However, the preparation process for natural rubber is backward and in urgent need of reform. Electrophoretic coagulation, as a new natural rubber coagulation process, was proposed in this paper. We designed electrophoresis equipment and optimized it through finite element analysis. Compared with traditional coagulation methods electrophoretic coagulation has outstanding advantages: high efficiency, no wastewater, and low odor. Compared with commercial natural rubber, electrophoretic coagulated natural rubber has a stronger supramolecular structure, better mechanical performances, and dynamic compression heat buildup. We also revealed the relationship between the structure and properties of different natural rubber. [ABSTRACT FROM AUTHOR]

In this work, we present the sensitive and selective determination of the widely used insecticide nitenpyram (NIT), utilizing a newly developed dual detection concept (DDC) for capillary electrophoresis (CE). This DDC was realized by combining two complementary detection principles, namely amperometric detection (AD) and mass spectrometry (MS), using a commercially available flow splitter (CE‐AD/MS). The novel DDC was implemented utilizing a newly developed, modular, and user‐friendly CE system with a unique capillary positioning mechanism to improve the workflow. A detailed description of the CE device can be found in the Supporting Information. We investigated the analytical performance of the novel DDC (CE‐AD/MS) in the context of NIT determination. The NIT LOD, obtained by AD, was up to a factor of 14 lower than in case of MS in the context of CE‐AD/MS. The qualitative and quantitative determination of NIT in pharmaceutical samples is presented as a possible application for the novel DDC. Additionally, the oxidation process during AD was examined by hyphenation of electrochemistry to CE‐MS. [ABSTRACT FROM AUTHOR]

The article focuses on the exploration of Enceladus, a moon of Saturn, as a potential site for extraterrestrial life. Topics discussed include the discovery of plumes of water erupting from Enceladus, the development of analytical instruments such as capillary electrophoresis for detecting signs of life in the subsurface ocean, and the challenges of conducting liquid-based separation science instruments during spaceflight.

Modeling of electrokinetic flows is crucial to understand numerous phenomena associated with electrochemistry, biophysics, and colloidal science. Here, we incorporate the modified Gaussian renormalized fluctuation theory into transport equations for electrolyte solutions to study the ion‐correlation‐induced inversion of electrokinetic flows, also known as charge inversion. We are able to capture the non‐monotonic dependence of inverted streaming current and reversed electrophoretic mobility on salt concentration. By analyzing the double‐layer structure, we elucidate that this non‐monotonicity is a consequence of the competition between spatially varying ion correlations and the translational entropy of the ions. We find that for practical values of surface charge densities, the excluded volume effect does not play any significant role. In a significant improvement over existing theories, our theoretical predictions are in quantitative agreement with experimental measurements for charge inversion in trivalent salts. [ABSTRACT FROM AUTHOR]

Background: The optimization of spermatozoa preparation techniques in order to obtain cell fractions enriched with structurally and functionally "superior" spermatozoa is a key objective of the assisted reproduction industry. Objectives: The purpose of this study was to evaluate a recent development of an electrophoretic spermatozoa separation device (Felix™, Memphasys Ltd, Sydney, Australia) and to compare its performance with conventional spermatozoa preparation by density gradient centrifugation (DGC). Particular attention was paid to the evaluation of sperm DNA/nuclear integrity. Materials & methods: A cohort of 29 human semen samples was studied. Semen samples were analyzed fresh and after DGC or Felix™ preparation. Semen parameters monitored included sample volume, sperm count, total motility, progressive motility, sperm DNA fragmentation using the Sperm Chromatin Structure Assay and sperm DNA oxidation. Results: Spermatozoa preparation with Felix™ resulted in significantly improved spermatozoa fractions with higher progressive motility, lower sperm DNA fragmentation, and lower sperm DNA oxidation compared with raw semen and DGC‐prepared spermatozoa. Discussion & conclusion: The data collected in this study support the preparation of spermatozoa by the Felix™ system as it allows selection of spermatozoa with the highest progressive motility as well as the lowest nuclear/DNA damage. These improved sperm parameters, along with the fact that the Felix™ separation process is very fast and highly standardized, should be of great interest to the assisted reproduction technologies industry. [ABSTRACT FROM AUTHOR]

The article focuses on identifying a novel splicing mutation in the Ectodysplasin A (EDA) gene within a hypohidrotic ectodermal dysplasia (HED) pedigree, exploring the molecular pathogenesis of HED through genetic testing technologies. Topics covered include the characterization of HED, involvement of specific genes like EDA, and the identification of various mutation types leading to HED, emphasizing the significance of this novel splicing mutation in the EDA gene within a Chinese family.

Simultaneously studying different biomarker types (DNA, RNA, proteins, etc.) could improve understanding and diagnosis of many complex diseases. However, biomarker detection involves several complex or expensive methodologies, requiring specialized laboratories and personnel. A multiplexed assay would greatly facilitate the use of biomarker data. Here, we present a multiplexed biomarker detection technique using variable‐length DNA payload chains, which are systematically disassembled in the presence of specific biomarkers. The resulting distinctly‐sized fragments yield characteristic gel electrophoresis band patterns. This has enabled us to detect with high sensitivity and specificity DNA sequences including BRCA1 (limit of detection, LOD, ∼3 nM), RNA (miR‐141, LOD ∼19 nM) and the steroids aldosterone and cortisol (LOD ∼200–250 nM). We show that our assay is multiplexable, and suffers limited sensitivity loss in fetal bovine serum and can be applied using capillary electrophoresis, which may be more amenable to automation and integration in healthcare settings. [ABSTRACT FROM AUTHOR]

Hereditary hemolytic anemia (HHA) is a heterogeneous group of disorders due to genetically caused defects in red blood cell membrane structure, enzymes, heme and globin synthesis, erythroid proliferation, and differentiation. Traditionally, the diagnostic process is complex and includes a plethora of tests from routine to highly specialized ones. The inclusion of molecular testing has significantly improved the diagnostic yield. The value of molecular testing is broader than just rendering the correct diagnosis, as it may also guide therapeutic decisions. As more molecular modalities become available for clinical use, it is imperative to understand their benefits and disadvantages pertaining to the HHA diagnostics. Re‐evaluation of the traditional diagnostic workflow may also bring forth additional benefits. This review focuses on the current state of molecular testing for HHA. [ABSTRACT FROM AUTHOR]

Hemoglobin disorders are among the most common genetic diseases worldwide. Molecular diagnosis is helpful in cases where the diagnosis is uncertain and for genetic counseling. Protein‐based diagnostic techniques are frequently adequate for initial diagnosis. Molecular genetic testing is pursued in some cases, particularly when a definitive diagnosis is not possible and especially for the purpose of assessing genetic risk for couples wanting to have children. The expertise available in the clinical hematology laboratory is essential for the diagnosis of patients with hemoglobin abnormalities. Initial diagnoses are made using protein‐based techniques such as electrophoresis and chromatography. Based on these findings, genetic risk to an individual's offspring can be assessed. In the setting of β‐thalassemia and other β‐globin disorders, coincident α‐thalassemia may be difficult to diagnose, which can have potentially serious consequences. In addition, unusual forms of β‐thalassemia caused by deletions in the β‐globin locus cannot be definitively characterized using standard techniques. Molecular diagnostic testing has an important role in the diagnosis of hemoglobin disorders and is important in the setting of genetic counseling. Molecular testing also has a role in prenatal diagnosis to identify fetuses affected by severe hemoglobinopathies and thalassemias. [ABSTRACT FROM AUTHOR]

Protein analysis is an important approach for disease diagnosis, in which sample pretreatment is an essential step since protein samples are often complex and many protein biomarkers are of low abundance. Here, given the good openness and light transmission of liquid plasticine (LP), which is a liquid entity formed by SiO2 nanoparticles and encapsulated aqueous solution, we developed a LP‐based field‐amplified sample stacking (FASS) system for protein enrichment. The system was composed of a LP container, a sample solution and a Tris‐HCl solution containing hydroxyethyl cellulose (HEC). The system design, mechanism investigation, optimization of experimental parameters and characterization of LP‐FASS performance for protein enrichment were well studied. Under the optimized experimental conditions of 1 % HEC, 100 mm Tris‐HCl and 100 V in the LP‐FASS system, a 40–80 times enrichment of proteins was obtained in 40 min using bovine hemoglobin (BHb) as the model protein using the constructed LP‐FASS system. The simultaneous enrichment of multiple proteins (phycocyanin, BHb and cytochrome C) was also realized using the system. The LP‐FASS system can serve as a new platform for protein enrichment which is easy to be combined with online and offline detections. [ABSTRACT FROM AUTHOR]

Background: Lactate dehydrogenase (LDH) and creatine kinase (CK) have differential tissue activity and isoenzyme profiles. LDH and CK exist as 5 and 3 isoenzymes, respectively, in both serum and cerebrospinal fluid (CSF). Studies have demonstrated that measuring LDH, CK, and their isoenzymes in CSF has diagnostic and prognostic values for dogs and people with neurologic disorders. Objectives: Iatrogenic blood contamination can distort the results of CSF analysis. The purpose of this study was to determine allowable thresholds of blood contamination (RBC/μL) for accurate measurement of LDH, CK, and their isoenzymes in canine CSF. Methods: Venous blood and CSF were collected from healthy dogs. Total LDH and CK activity were measured spectrophotometrically. Isoenzyme profiles were determined using gel electrophoresis and densitometric scanning. All samples were analyzed within 6 hours of collection. A nonlinear mixed effects regression model was used to estimate the allowable thresholds of blood contamination for accurate measurement of LDH, CK, and their isoenzymes in canine CSF. Results: The threshold of iatrogenic blood contamination for total LDH and total CK in healthy dogs are 6696 RBC/μL (95% CI 3879–11 187) and 5961 RBC/μL (95% CI 2939–12 085), respectively. LDH‐1 is the most sensitive isoenzyme to iatrogenic blood contamination, while LDH‐4 is the least sensitive. Conclusions: These results are important for the interpretation of LDH, CK, and their isoenzymes in canine CSF. Additionally, our methodology is translatable for determining thresholds of acceptable iatrogenic blood contamination in CSF for other diagnostic and prognostic biomarkers of neurologic disease. [ABSTRACT FROM AUTHOR]

To enable detailed studies of interactions between nanoparticles and their environment and the correlations between various nanoparticle properties, one must go beyond ensemble averages and toward single‐particle measurements. However, current methodologies for the single‐nanoparticle analysis of charge and size either lack the flexibility to study dynamic processes on the single‐particle level or are highly specific and require complex microfluidic devices. In addition, accurate measurements of the electrophoretic mobility (or zeta‐potential) based on the optical detection of single nanoparticles remain challenging due to the low photon budget, the required sampling frequency, and the fact that electroosmosis in typical microfluidic devices must be analyzed carefully. In this study, a method is investigated to accurately characterize the electrophoretic mobility of individual nanoparticles and estimate their size by simultaneously analyzing the electrokinetic‐ and Brownian motion in a simple microfluidic channel. Fast laser scanning excitation and sensitive detection of fluorescent photons enable single‐nanoparticle velocimetry experiments in an oscillating electric field at high frame rates. [ABSTRACT FROM AUTHOR]

Immunoglobulins in bovine colostrum were separated and fractionated from other proteins using the method and instrumentation developed in our laboratory. The proposed separation was based on bidirectional isotachophoresis/moving boundary electrophoresis with electrofocusing of the analytes in a pH gradient from 3.9 to 10.1. The preparative instrumentation included the trapezoidal non‐woven fabric that served as separation space with divergent continuous flow. The defatted and casein precipitate‐free colostrum supernatant was loaded directly into the instrument without any additional colostrum pre‐preparation. Immunoglobulin G was fractionated from other immune proteins such as bovine serum albumin, β‐lactoglobulin, and α‐lactalbumin, and was continuously collected in separated fractions over 3 h. The fractions were further processed, and isolated immunoglobulin G in the liquid fractions was confirmed by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis and by re‐focusing in gel isoelectric focusing. Separated immunoglobulin G was detected in seven fractions by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis with a gradually decreased concentration in the fractions. Re‐focusing of the proteins in the fractions by gel isoelectric focusing revealed multiple separated zones of immunoglobulin G with the isoelectric point values covering the range from 5.4 to 7.2. Each fraction contained distinct zones with gradually increased isoelectric point values and decreased concentrations from fraction to fraction. [ABSTRACT FROM AUTHOR]

The preparative gel electrophoresis enables the separation of nano‐ and submicron particles based on different electrophoretic mobilities. In this contribution, we show that a fractionation not only by particle size is possible, but also by surface charge/chemistry and morphology. Whilst this method, in analogy to its application in biotechnology, is yet restricted to small quantities, possibilities for an increase of the particle throughput as well as for a continuous separation are shown. [ABSTRACT FROM AUTHOR]

The combination of a microarc oxidation (MAO) film and water‐based electrophoresis painting (EP) technology is a promising surface treatment for magnesium alloys, but the matching performance between them has not been investigated systematically. For fabricating the optimal composite coating, the influence of the MAO film condition and electrophoresis parameters on the overall performance of the composite coating was investigated by scanning electron microscopy, finite element modeling, electrochemical impedance spectroscopy, and immersion tests. The results indicate that the composite coating with an MAO voltage of 330 V and an EP voltage of 120 V shows the best corrosion resistance. Its excellent anticorrosion performance is attributed to the suitable thickness ratio of the MAO/EP coating and the excellent mechanical interlock effect of the MAO/EP interface. The microstructure of the MAO coating plays a key role; the uniform micropore size promotes a uniform electric field distribution in the initial electrophoresis process, which can considerably improve the sealing pore quality of the EP resin and further maximize the interfacial adhesion strength. [ABSTRACT FROM AUTHOR]

Restrictive cardiomyopathy secondary to cardiac amyloidosis is an underdiagnosed, but treatable, cause of heart failure involving an extracellular deposition of misfolded protein. Hereby, we report a case of a female patient with history of nephrotic syndrome for 1 year who subsequently presented with symptoms of heart failure. The findings on cardiac imaging supported the suspicion of cardiac amyloidosis. Further laboratory workup for amyloidosis was pursued along with endomyocardial biopsy which confirmed amyloidosis‐AL type. Patient was started on chemotherapy. The case underscores the importance of a timely diagnosis with the help of symptomatology and imaging along with a multidisciplinary approach for patient care. [ABSTRACT FROM AUTHOR]

Background: Hyperglobulinemia is reported in 26% of canine chronic B‐cell lymphocytic leukemia (B‐CLL) cases. However, few cases have been characterized by protein electrophoresis and immunofixation (IF), and the incidence of a monoclonal protein (M‐protein) is unknown using these techniques. Objective: To characterize and determine the proportion of canine B‐CLL cases with an M‐protein using plasma protein electrophoresis (PPE), routine and free light chain (fLC) IF, and to assess if productive B‐CLL cases express MUM1/IRF4 by cell tube block (CTB). Methods: PPE, routine (targeting IgG, IgA, IgM, IgG4, and light chain) and fLC IF were performed using 48 dog B‐CLL plasma samples from patients diagnosed via peripheral blood flow cytometry. CTB was performed on a separate cohort of 15 patients. Results: Hyperproteinemia (>7.5 g/dL) was present in 17/48 cases (35%). An M‐protein was detected in 32/48 cases (67%). Of these, 19/32 cases (59%) had only complete (monoclonal heavy and light chain) M‐proteins detected, 10/32 cases (31%) had both complete and fLC M‐proteins detected, and 3/32 cases (9%) had only an fLC M‐protein detected. IgM was the most common clonal immunoglobulin isotype detected (23 cases). CD21+ cell counts were higher in cases with detectable M‐protein. Plasma fLC IF suggested β‐γ region interference, likely caused by clotting proteins. All B‐CLL cases consistently expressed PAX5 and did not express MUM1/IRF4. Conclusions: Most B‐CLL cases had an M‐protein and were not hyperproteinemic. Most cases with paraproteins had a complete IgM monoclonal gammopathy; a subset had documented fLCs. The prognostic significance of heavy and fLC presence should be evaluated. [ABSTRACT FROM AUTHOR]

RETRACTION: R. Bakalova, H. Ohba, Z. Zhelev, T. Kubo, M. Fujii, M. Ishikawa, Y. Shinohara, and Y. Baba, 'Antisense inhibition of Bcr‐Abl/c‐Abl synthesis promotes telomerase activity and upregulates tankyrase in human leukemia cells,' FEBS Letters 564, no. 1–2 (2004): 73–84, https://doi.org/10.1016/S0014‐5793(04)00318‐7. The above article, published online on 9 April 2004 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the authors; the journal Editor‐in‐Chief, Michael Brunner; FEBS Press; the National Institute of Advanced Industrial Science and Technology (AIST); and John Wiley and Sons Ltd. Following publication, concerns were raised by a third‐party regarding several figures in the article. The subsequent institutional investigation conducted by the AIST revealed:Inappropriate duplication of image panels within the article, between the β‐actin loading controls for 4 and 6 days in the Western blot of Fig. 2A K‐562; between the subpanels of the electrophoresis blots in Fig. 4A K‐562 and Jurkat cells; and between the subpanels of the electrophoresis blots in Fig. 6B.Band insertion in the Western blot of Fig. 6A p210 Bcr‐Ab lane.Inappropriate duplication of images between this article (Fig. 2A K562 β‐actin and Fig. 4B K562 6 days treatment bands) and an earlier publication from 2003 by an overlapping group of authors representing different experimental conditions.Inappropriate duplication and modification of an image between this article (Figure 3A2) and an earlier publication from 2004 by an overlapping group of authors representing different experimental conditions. Therefore, the conclusions of the paper are substantially compromised and the institute has recommended the paper to be retracted. The editors of the journal agree with the retraction based on the institutional investigation. [ABSTRACT FROM AUTHOR]

In this work, we demonstrate a UV‐NIR broadband carbon black shutter that exhibits energy saving by NIR reflection, high contrast ratio in a visible wavelength, and no discoloration and blocking UV. The black and transparent state in a carbon black dispersed cell is realized by controlling position of particles with electrophoretic force. We believe that this approach can pave a way for developing new electrophoretic broadband shutters for privacy, energy efficient automobiles and buildings or a UV sensitive environment. [ABSTRACT FROM AUTHOR]

A chitosan composite with a vertical array of pore channels is fabricated via an electrophoretic deposition (EPD) technique. The composite consists of chitosan and polyethylene glycol, as well as nanoparticles of silver oxide and silver. The formation of hydrogen bubbles during EPD renders a localized increase of hydroxyl ions that engenders the precipitation of chitosan. In addition, chemical interactions among the constituents facilitate the establishment of vertical channels occupied by hydrogen bubbles that leads to the unique honeycomb‐like microstructure; a composite with a porosity of 84%, channel diameter of 488 µm, and channel length of 2 mm. The chitosan composite demonstrates an impressive water uptake of 2100% and a two‐stage slow release of silver. In mass transport analysis, both Disperse Red 13 and ZnO powders show a much enhanced transport rate over that of commercial gauze. Due to its excellent structural integrity and channel independence, the chitosan composite is evaluated in a passive suction mode for an adhesive force of 9.8 N (0.56 N cm−2). The chitosan composite is flexible and is able to maintain sufficient adhesive force toward objects with different surface curvatures. [ABSTRACT FROM AUTHOR]

The aim of this study is to develop a reference interval for plasma protein electrophoresis for wild free‐roaming central bearded dragons (Pogona vitticeps). This will assist the veterinarian in diagnosing and monitoring diseases in wild and captive animals. The study group consisted of 29 wild central bearded dragons of which 22 were males and 7 were females. The plasma samples were obtained from animals in a previous study and were stored frozen at −20°C for 2–3 years before analysis. Plasma protein electrophoresis was performed on 100 uL of plasma. The data were evaluated for the difference between reproductively active females and pooled males with non‐reproductively active females as well as the difference between biochemical and protein electrophoresis albumin. Biochemical albumin was found to be significantly higher than electrophoresis albumin in all animals, with a mild proportional bias present. Plasma protein electrophoresis identified albumin, α − 1 and 2, β − 1 and 2 and γ fractions. The reproductively active females in this study exhibited results that were distinct from pooled males and non‐reproductively active females. This study provides a reference interval for plasma protein electrophoresis in central bearded dragons that can be used as a tool for health and disease monitoring and diagnosis. The importance of the use of method and sex/season appropriate reference intervals in reptile medicine is confirmed in this study. [ABSTRACT FROM AUTHOR]

This paper uses zone electrophoresis, one of the most frequently used tools in molecular biology, to explore two ideas derived from Hans-Jörg Rheinberger's reflections on experiments. First, the constraining role played by technical objects--instrumentation and material conditions--in the production of knowledge or epistemic things. Second, the production of interconnected experimental systems by such technical objects, which results in the unexpected entanglement of research fields and experimental cultures. By the beginning of the 1960s, the inception of zone electrophoresis in laboratories around the world transformed--some say, revolutionized--the study of proteins. Even today, electrophoresis continues to open research venues and questions in biomedicine, molecular biology, human genetics, and in the field of molecular evolution. In my essay, I seek to look at the interconnected lives of zone electrophoresis and address the broader social, and even global context, in which this apparently humble technique became a salient tool in the production of biological knowledge. In so doing, I aim to take the past and present of the history and historiography of experimental systems to the future, where experiments and technologies are interrogated as they are used in different geographies and contexts, including contexts of poverty. [ABSTRACT FROM AUTHOR]

There is a need for specific determination of blood group antigens on erythrocytes for improvement of the quality of hemotransfusion therapy. O, A, B, AB, and weak variants of A and B antigen (O washed erythrocytes with anti‐A or anti‐B antibody absorbing ability) were investigated for electrophoretic mobility with immunoglobulin G complement‐dependent antibodies. The contact of anti‐A heated serum and complement with A erythrocytes resulted in their decreased electrokinetic potential the contrary to the serum without anti‐A and anti‐B antibodies and increased after addition of the serum from O blood group person with anti‐A and anti‐B absorbing ability. Anti‐B heated serum with complement decreased electrokinetic potential of B erythrocytes. Whereas both anti‐A heated serum and serum from AB person with complement did not decrease the electrokinetic potential of O erythrocytes. Anti‐B heated serum, in the same manner, decreased the electrokinetic potential of O blood group erythrocytes with anti‐B absorbing ability. Anti‐А immunoglobulin G complement‐dependent antibodies decreased the electrokinetic potential of washed O erythrocytes with аnti‐A absorbing ability contrary to immunoglobulin M antibodies. Evaluation of the electrokinetic potential of erythrocytes with a set of immunoglobulin G complement‐dependent antibodies might be considered for blood group type detection. [ABSTRACT FROM AUTHOR]

Introduction: Human umbilical cord blood is rich in hematopoietic cells. We aimed to focus on the morphological, biochemical, membrane protein profile and surface protein expression differences of erythrocytes, isolated from cord and adult peripheral blood using techniques such as high‐resolution scanning electron microscopy (SEM), gel electrophoresis (SDS‐PAGE) and flow cytometry. Methods: Adult peripheral blood was collected from consenting adults, and umbilical cord blood was procured from consenting mothers, post‐delivery at Medical College, Kolkata. We emphasized on cord and adult peripheral blood erythrocytes' morphological variations using SEM images and protein expression by flow cytometric analysis. Some conventional biochemical analyses such as osmotic fragility of the cell membrane, haemoglobin co‐oxidation study and lipid peroxidation assay were done for supporting evidence along with membrane protein content using gel electrophoresis. Results: Our SEM images indicated clear morphological variations in cord erythrocyte with a higher degree of cellular deformities and difference in membrane texture. Flow cytometric analysis of cord erythrocyte showed a significant difference in CD235a expression than adults. We observed an overexpression of GLUT1 and decreased expression of Band 3 in cord erythrocyte membrane. Our results also showed cord erythrocytes have low osmotic fragility, a slower rate of co‐oxidation of cord haemoglobin and a lesser lipid peroxidation level than that of adults. Conclusion: Cord blood erythrocytes have deeper indentations leading to higher flexibility, more oxygen‐carrying capacity and less osmotic fragility in comparison with adult erythrocytes. The expression of CD235a and Band 4.5 (GLUT 1) was significantly higher in cord erythrocytes than peripheral adult erythrocytes. [ABSTRACT FROM AUTHOR]

The article offers information about verification of a new semi-automated Von Willebrand factor multimers assay. It mentions that Von Willebrand factor (VWF) plays an important role in normal haemostasis by facilitating platelet adhesion and aggregation at sites of high shear stress or vascular damage.

We report that ionic current gradients and corresponding electric field gradients formed at bipolar electrodes are useful for enriching cations up to ∼350‐fold at specific locations in microfluidic devices. The enrichment mechanism is determined by collecting current data, measuring solution conductivity, and by performing pH indicator experiments. These data reveal the dynamic nature of the enrichment mechanism. Specifically, they show the complex relationship between the ionic current gradients formed at the bipolar electrode and the extent of cation enrichment. Finally, we demonstrate cation enrichment is possible in buffer‐free solutions containing up to 50.0 mM KCl. This finding is significant because it broadens the range of solutions in which membrane‐free, electrochemical separations using bipolar electrodes can be performed. [ABSTRACT FROM AUTHOR]

Common delivery routes for chemotherapeutics are based on circulation, which faces clinical limitations to local delivery efficiency, and the conflict between the dose for anticancer effect and the systemic toxicity. The recent advances in localized delivery strategies aim to improve drug accumulation at the target site or directly transport into cells. However, most are not equipped to provide additional momentum in the process of cargo release, propagation, and intracellular movement, which limit their locomotion that relies on passive diffusion. In this work, a multimicrochannel microneedle microporation (4M) platform that achieves high efficiency, safety, and uniformity for in vivo intracellular delivery is proposed. By high precision 3D printing, internal microchannels are implemented through the microneedle, which offer a concentrated, safe electric field that not only accelerates the movement of cargo into deep tissue under electrophoresis, but also triggers cell electroporation, achieving enhanced transport across cell membrane. The platform proves efficient for the delivery of chemotherapeutics in solid tumors in vitro and in vivo, with significantly enhanced anticancer effect and reduced systemic toxicity. The platform serves as a general‐purpose delivery tool to emerging drugs in vivo. [ABSTRACT FROM AUTHOR]

Sample preparation and protein fractionation are important issues for proteomic studies. Protein extraction procedures strongly affect the performance of fractionation methods by provoking protein dispersion in several fractions. The most notable exception is the gel‐based electrophoretic protein fractionation due to its resolution and effectiveness of sodium dodecyl sulfate as a solubilizing agent, while its main limitation lies in the poor recovery of the gel‐trapped proteins. We created a fractionator device to separate complex mixture of proteins and peptides that is based on the continuous gel electrophoresis/electroelution sorting of these molecules. In an unsupervised process, complex mixtures of proteins or peptides are fractionated into the gel while separated fractions are simultaneously and sequentially electroeluted to the solution containing wells. The performance of the device was studied for protein fractionation in terms of reproducibility, protein recovery, and loading capacity. In a setup free of sodium dodecyl sulfate, complex peptide mixtures can also be fractionated. More than 11,700 proteins were identified in the whole‐cell lysate of the CaSki cell line by using the fractionator combined with the filter‐aided sample preparation method and mass spectrometry analysis. Fractionator‐based proteome characterization increased 1.7‐fold the number of identified proteins compared to the unfractionated sample analysis. [ABSTRACT FROM AUTHOR]

Microfluidic free‐flow electrophoresis (μ‐FFE) is widely used for continuous separation of charged analytes. However, μ‐FFE is limited in the separation of analytes with the same electrophoretic mobility. In this work, we developed a novel microfluidic free‐flow paper electrochromatography (μ‐FFPE) by combining μ‐FFE with filter paper‐based chromatography, enabling continuous separation of analytes through the mechanism of both μ‐FFE and paper chromatography. Numerical simulation was applied to demonstrate the advantages of adding filter paper as the stationary phase of μ‐FFE. With the filter paper, a more stable separation system was achieved. The device was applied to the separation of simple mixtures of dyes and complex mixtures of glycans. With the μ‐FFPE fractionation, much more glycans and glycan types can be identified by LC‐MS, demonstrating the value of the method in biological analysis. The μ‐FFPE can provide a new platform for the separation and analysis of various biological molecules. [ABSTRACT FROM AUTHOR]

Buffer solutions are pervasive in chemistry, biochemistry, analytical chemistry, etc. A better understanding of buffer properties and what controls them is susceptible to be of interest in many scientific and technological fields. For instance, linear pH gradients are commonly used in electrophoresis and their optimization rests on numerical optimization of the concentrations of various weak species. It is probably generally assumed that no basic progress could be made on optimization approaches. We introduce here a new strategy to buffer optimization, based on a parametric study of the roots of the first derivative of the buffer index. In this way, it is possible to find mathematically optimal sets of parameters (pKa and concentrations). The method is applied to mixtures of 2, 3 and 4 monovalent species, which represent simple cases that do not call for overly elaborate numerical optimization techniques, but are nevertheless of practical interest in various branches of analytical chemistry. [ABSTRACT FROM AUTHOR]

Organic electronic ion pumps (OEIPs) have been investigated as a promising solution for precise local delivery of biological signaling compounds. OEIP miniaturization provides several advantages, ranging from better spatiotemporal control of delivery to reduced invasiveness for implanted devices. One miniaturization route is to develop OEIPs based on polyelectrolyte‐filled capillary fibers. These devices can be easily brought into proximity of targeted cells and tissues and could be considered as a starting point for other "iontronic" implants. To date, OEIPs and other such iontronics exhibit a limited electrode capacity as they generally rely on poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) electrodes. While this material is well studied and viable in mixed ion‐electron systems, its bulk capacitance is limited by eventual redox reactions. Graphene is an excellent alternative for high‐performance electrodes and low‐cost solution‐processed graphene derivatives are particularly promising, exhibiting high charge mobility and ideal structural properties (lightness, flexibility). Here, the application of solution‐processed reduced graphene oxide (RGO) as high‐performance driving electrodes for OEIPS is presented. RGO electrodes are characterized and compared with standard PEDOT:PSS (and Ag/AgCl) electrodes. The RGO exhibits greater charge storage capacity and thus increased operational lifetime. The graphene‐enabled OEIPs exhibit improved neurotransmitter transport, without imposing limitations to the applied current level. [ABSTRACT FROM AUTHOR]

The dynamic and static properties of structured surfaces have important functions in nature. In particular, wrinkles have important static roles, for example, increasing surface area, but dynamic roles of wrinkles remain poorly understood. Specifically, to understand and utilize the dynamic functions of wrinkles, it is necessary to observe wrinkle formation directly. In this study, a polyion complex (PIC) is formed on a hydrogel surface by electrophoresis, and the process of wrinkle formation through a transparent electrode is directly observed. By quantitative analysis of the wavelength and amplitude of wrinkles, it is found that the wrinkles move randomly in a wavy pattern in the initial stage of growing process. Furthermore, the direction of wavy motion of wrinkles is controlled by the compression of hydrogels in the in‐plane direction. The present study provides important insights into the fabrication of wrinkled surfaces with a controlled flow direction; opening the possibility for active wrinkles used in the development of functional surface structures as actuators that are capable of transporting small objects in water. [ABSTRACT FROM AUTHOR]

Capillary electrophoresis (CE) has been proven to be a performant analytical method to analyze both small and macro molecules. Indeed, it is capable of separating compounds of the same nature according to differences in their charge to size ratios, particularly proteins, monoclonal antibodies and peptides. However, one of the major obstacles to reach high separation efficiency remains the adsorption of solutes on the capillary wall. Among the different coating approaches used to control and minimize solute adsorption, polyelectrolyte multilayers can be applied to CE as a versatile approach. These coatings are made up of alternating layers of polycations and polyanions, and may be used in acidic, neutral or basic conditions depending on the solutes to be analyzed. This Review provides an overview of Successive Multiple Ionic‐polymer Layer (SMIL) coatings used in CE, looking at how different parameters induce variations on the electro‐osmotic flow (EOF), separation efficiency and coating stability, as well as their promising applications in the biopharmaceutical field. [ABSTRACT FROM AUTHOR]

Aim: To introduce a quantitative determination of heparan sulfate and dermatan sulfate by mass spectrometry and to compare it with two‐dimensional electrophoresis of the glycosaminoglycans in the amniotic fluid for the prenatal diagnosis of mucopolysaccharidoses type II (MPS II). Methods: Thirty pregnancies each with single fetus were subjected to amniocentesis at 16 weeks: 10 with a previously affected MPS II infant and 20 as controls. Prenatal diagnosis was done by both mass spectrometry two two‐dimensional electrophoresis. Results: Two‐dimensional electrophoresis showed four affected with MPS II and six unaffected fetuses. Mass spectrometry verified these results. Conclusion: Two‐dimensional electrophoresis of the glycosaminoglycans in amniotic fluid is a good qualitative method and mass spectrometry is a new accurate quantitative method for prenatal diagnosis of MPS II. Quantitative determination of glycosaminoglycans in amniotic fluid by mass spectrometry is both rapid and accurate. Prenatal diagnosis is recommended for at risk pregnancies and mass spectrometry offers speed and quantitation. [ABSTRACT FROM AUTHOR]