Capillary and microchip electrophoresis plays an important role in the analysis of the chemical composition of plants and nutrient soils, which finds applications in plant physiology, agrochemistry, medicine, toxicology and food science. Electrophoretic methods are used to determine minerals such as nutrients, heavy metal ions, primary and secondary metabolites, herbicides, phytohormones, peptides, proteins and extracellular vesicles. Progress is particularly evident in the following topics: i) development of mobile electrophoretic analysers for field-based monitoring of soil mineral supply, ii) direct analysis of xylem sap without sample treatment, iii) coupling of capillary and microchip electrophoresis with mass spectrometry for comprehensive metabolome and proteome characterization, iv) determination of secondary metabolites as biologically active compounds with a range of therapeutic and toxicological effects, v) monitoring of herbicides and their degradation dynamics, vi) research on plant exudates, extracellular vesicles and specific protein interactions.
- MeSH
- Electrophoresis, Capillary methods MeSH
- Herbicides analysis MeSH
- Mass Spectrometry MeSH
- Plants * chemistry metabolism MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
Proteomics provides an understanding of biological systems by enabling the detailed study of protein expression profiles, which is crucial for early disease diagnosis. Microfluidic-based proteomics enhances this field by integrating complex proteome analysis into compact and efficient systems. This review focuses on developing microfluidic chip structures for proteomics, covering on-chip sample pretreatment, protein extraction, purification, and identification in recent years. Furthermore, our work aims to inspire researchers to select proper methodologies in designing novel, efficient assays for proteomics applications by analyzing trends and innovations in this field.
- MeSH
- Biosensing Techniques instrumentation methods MeSH
- Equipment Design MeSH
- Lab-On-A-Chip Devices * MeSH
- Humans MeSH
- Microfluidics methods MeSH
- Microfluidic Analytical Techniques instrumentation MeSH
- Proteins analysis isolation & purification MeSH
- Proteome analysis isolation & purification chemistry MeSH
- Proteomics * methods MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
This study investigates various microfluidic chip fabrication techniques, highlighting their applicability and limitations in the context of urgent diagnostic needs showcased by the COVID-19 pandemic. Through a detailed examination of methods such as computer numerical control milling of a polymethyl methacrylate, soft lithography for polydimethylsiloxane-based devices, xurography for glass-glass chips, and micromachining-based silicon-glass chips, we analyze each technique's strengths and trade-offs. Hence, we discuss the fabrication complexity and chip thermal properties, such as heating and cooling rates, which are essential features of chip utilization for a polymerase chain reaction. Our comparative analysis reveals critical insights into material challenges, design flexibility, and cost-efficiency, aiming to guide the development of robust and reliable microfluidic devices for healthcare and research. This work underscores the importance of selecting appropriate fabrication methods to optimize device functionality, durability, and production efficiency.
- MeSH
- COVID-19 * virology MeSH
- Equipment Design MeSH
- Dimethylpolysiloxanes chemistry MeSH
- Lab-On-A-Chip Devices * MeSH
- Humans MeSH
- Microfluidics methods instrumentation MeSH
- Microfluidic Analytical Techniques instrumentation methods MeSH
- Polymethyl Methacrylate chemistry MeSH
- SARS-CoV-2 isolation & purification MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Comparative Study MeSH
As organoids and organ-on-chip (OoC) systems move toward preclinical and clinical applications, there is an increased need for method validation. Using a liquid chromatography-mass spectrometry (LC-MS)-based approach, we developed a method for measuring small-molecule drugs and metabolites in the cell medium directly sampled from liver organoids/OoC systems. The LC-MS setup was coupled to an automatic filtration and filter flush system with online solid-phase extraction (SPE), allowing for robust and automated sample cleanup/analysis. For the matrix, rich in, e.g., protein, salts, and amino acids, no preinjection sample preparation steps (protein precipitation, SPE, etc.) were necessary. The approach was demonstrated with tolbutamide and its liver metabolite, 4-hydroxytolbutamide (4HT). The method was validated for analysis of cell media of human stem cell-derived liver organoids cultured in static conditions and on a microfluidic platform according to Food and Drug Administration (FDA) guidelines with regards to selectivity, matrix effects, accuracy, precision, etc. The system allows for hundreds of injections without replacing chromatography hardware. In summary, drug/metabolite analysis of organoids/OoCs can be performed robustly with minimal sample preparation.
- MeSH
- Chromatography, Liquid methods MeSH
- Solid Phase Extraction MeSH
- Mass Spectrometry methods MeSH
- Liver * metabolism MeSH
- Liquid Chromatography-Mass Spectrometry MeSH
- Small Molecule Libraries analysis metabolism chemistry MeSH
- Lab-On-A-Chip Devices MeSH
- Pharmaceutical Preparations metabolism analysis MeSH
- Humans MeSH
- Organoids * metabolism cytology MeSH
- Tolbutamide metabolism analysis MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Validation Study MeSH
INTRODUCTION: This study aimed to evaluate the occurrence of clinically relevant (sub)microscopic chromosomal aberrations in fetuses with the nuchal translucency (NT) range from 3.0 to 3.4 mm, which would be potentially missed by cfDNA testing. METHODS: A retrospective data analysis of 271 fetuses with NT between 3.0 and 3.4 mm and increased first trimester combined test (CT) risk in five cohorts of pregnant women referred for invasive testing and chromosomal microarray was performed. RESULTS: A chromosomal aberration was identified in 18.8% fetuses (1:5; 51/271). In 15% (41/271) of cases, trisomy 21, 18, or 13 were found. In 0.7% (2/271) of cases, sex chromosome aneuploidy was found. In 1.1% (3/271) of cases, CNV >10 Mb was detected, which would potentially also be detected by genome-wide cfDNA testing. The residual risk for missing a submicroscopic chromosome aberration in the presented cohorts is 1.8% (1:54; 5/271). CONCLUSION: Our results indicate that a significant number of fetuses with increased CT risk and presenting NT of 3.0-3.4 mm carry a clinically relevant chromosomal abnormality other than common trisomy. Invasive testing should be offered, and counseling on NIPT should include the test limitations that may result in NIPT false-negative results in a substantial percentage of fetuses.
- MeSH
- Chromosome Aberrations MeSH
- Chromosome Disorders diagnosis genetics MeSH
- Adult MeSH
- Cohort Studies MeSH
- Humans MeSH
- Nuchal Translucency Measurement * MeSH
- Microarray Analysis MeSH
- Noninvasive Prenatal Testing methods MeSH
- Retrospective Studies MeSH
- Pregnancy MeSH
- Cell-Free Nucleic Acids blood genetics MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Pregnancy MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Multicenter Study MeSH
The application of microfluidic devices as next-generation cell and tissue culture systems has increased impressively in the last decades. With that, a plethora of materials as well as fabrication methods for these devices have emerged. Here, we describe the rapid prototyping of microfluidic devices, using micromilling and vapour-assisted thermal bonding of polymethyl methacrylate (PMMA), to create a spheroid-on-a-chip culture system. Surface roughness of the micromilled structures was assessed using scanning electron microscopy (SEM) and atomic force microscopy (AFM), showing that the fabrication procedure can impact the surface quality of micromilled substrates with milling tracks that can be readily observed in micromilled channels. A roughness of approximately 153 nm was created. Chloroform vapour-assisted bonding was used for simultaneous surface smoothing and bonding. A 30-s treatment with chloroform-vapour was able to reduce the surface roughness and smooth it to approximately 39 nm roughness. Subsequent bonding of multilayer PMMA-based microfluidic chips created a durable assembly, as shown by tensile testing. MDA-MB-231 breast cancer cells were cultured as multicellular tumour spheroids in the device and their characteristics evaluated using immunofluorescence staining. Spheroids could be successfully maintained for at least three weeks. They consisted of a characteristic hypoxic core, along with expression of the quiescence marker, p27kip1. This core was surrounded by a ring of Ki67-positive, proliferative cells. Overall, the method described represents a versatile approach to generate microfluidic devices compatible with biological applications.
Zvyšující se výskyt antibiotických rezistencí patří k závažným problémům 21.století. Výskyt bakteriálních kmenů rezistentních k antibiotikům následně zužuje spektrum vhodných antibiotik použitelných pro léčbu i běžných bakteriálních infekcí nebo pro prevenci jejich výskytu, např. v chirurgii. Čistírny odpadních vod, nemocnice, ale i potravinový řetězec patří k ohniskům, kde nejčastěji dochází ke vzniku či šíření nových i stávajících kmenů bakterií rezistentních k antibiotikům a genů rezistence k antibiotikům. Ke stanovení antibiotických rezistencí se v laboratořích standardně používají fenotypové kultivační metody, které jsou však náročné na čas i práci a částečně i přesnou interpretaci výsledků. Z tohoto důvodu jsou hledány rychlejší alternativní metody detekce bakterií rezistentních k antibiotikům nebo přímo genů rezistence k antibiotikům. Příkladem alternativní metody detekce bakterií rezistentních k antibiotikům je například použití fenotypové metody využívající hmotnostní spektrometrie s laserovou desorpcí a ionizací za účasti matrice s průletovým analyzátorem pro stanovení producentů beta-laktamas. Zrychlení a zároveň větší přesnost detekce poskytují genotypové metody. Pomocí polymerasové řetězové reakce lze přímo detekovat a kvantifikovat geny rezistence k antibiotikům. Pro další zrychlení a vyšší specifitu detekce amplikonů z PCR lze použít mikročipy. Metody masivního paralelního sekvenování poskytují ucelenou informaci o rezistomu daného prostředí. Umožňují sekvenovat DNA amplikony či jednotlivé molekuly DNA pro detekci determinant antibiotické rezistence. Metody masivního paralelního sekvenování mají potenciál nahradit konvenční charakterizaci patogenů a umožňují detekci všech mikroorganismů ve vzorku (včetně obtížně kultivovatelných či nekultivovatelných mikroorganismů).
The increasing occurrence of antibiotic resistance is one of the major problems of the 21st century. The occurrence of bacterial strains resistant to antibiotics subsequently narrows the spectrum of suitable antibiotics usable for the treatment of common bacterial infections or for the prevention of their occurrence, e.g., in surgery. Wastewater treatment plants, hospitals, and also the food chain belong to the hotspots, where the emergence and spread of new or existing strains of antibiotic resistant bacteria and antibiotic resistance genes occur most frequently. Phenotypic culture methods are routinely used in laboratories to determine antibiotic resistance, but they are laborious and time-consuming and the interpretation of exact results is also difficult. For this reason, faster alternatives for the detection of antibiotic resistant bacteria or even antibiotic resistance genes are sought. Such an example of an alternative method for the detection of antibiotic resistant bacteria is the use of the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry phenotypic method to identify the beta-lactamase producers. Genotype methods provide faster analysis and, at the same time, more accurate detection. Antibiotic resistance genes can be directly detected and quantified by polymerase chain reaction. Microarrays can be used to further speed up and increase the specificity of PCR amplicons detection. Massive parallel methods provide comprehensive information on the resistoma of the specific environment. They facilitate sequencing of individual DNA molecules or amplicons to detect determinants of antibiotic resistance. Massive parallel methods have the potential to replace conventional pathogen characterization and allow the detection of all microorganisms in a sample (including difficult-to-cultivate or noncultivable microorganisms).
- MeSH
- Drug Resistance, Microbial * genetics MeSH
- Microbial Sensitivity Tests methods MeSH
- Microbiological Techniques * classification methods MeSH
- Polymerase Chain Reaction methods MeSH
- Oligonucleotide Array Sequence Analysis methods MeSH
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization methods MeSH
- High-Throughput Nucleotide Sequencing methods MeSH
- Publication type
- Review MeSH
Electrochemical methods can be used not only for the sensitive analysis of proteins but also for deeper research into their structure, transport functions (transfer of electrons and protons), and sensing their interactions with soft and solid surfaces. Last but not least, electrochemical tools are useful for investigating the effect of an electric field on protein structure, the direct application of electrochemical methods for controlling protein function, or the micromanipulation of supramolecular protein structures. There are many experimental arrangements (modalities), from the classic configuration that works with an electrochemical cell to miniaturized electrochemical sensors and microchip platforms. The support of computational chemistry methods which appropriately complement the interpretation framework of experimental results is also important. This text describes recent directions in electrochemical methods for the determination of proteins and briefly summarizes available methodologies for the selective labeling of proteins using redox-active probes. Attention is also paid to the theoretical aspects of electron transport and the effect of an external electric field on the structure of selected proteins. Instead of providing a comprehensive overview, we aim to highlight areas of interest that have not been summarized recently, but, at the same time, represent current trends in the field.
Ciele: Analýza prenatálnych vzoriek za obdobie 2015–2020. Porovnanie miery detekcie klinicky relevantných variant cytogenetickou analýzou karyotypu a cytogenomickými metódami MLPA (Multiplex Ligation-Depent Probe Amplification) a mikročipmi (CMA – chromosomal microarray). Súbor a metodika: Analyzovaných bolo 1 029 prenatálnych vzoriek cytogenetickým hodnotením karyotypu (n = 1 029), cytogenomickými metódami MLPA (n = 144) a CMA (n = 111). Všetky nebalansované zmeny boli potvrdené metódou MLPA alebo CMA. Výsledky: Z analyzovaného súboru plodov, po odčítaní aneuploidií – 107 (10,40 %, n = 1 029), bolo analýzou karyotypu zachytených 22 štruktúrnych aberácií (2,39 %, n = 922) – deväť nebalansovaných zmien (0,98 %), 10 balansovaných zmien (1,08 %), jeden prípad nejasnej mozaiky (0,09 %), jeden prípad prítomnosti marker chromozómu (0,09 %) a jeden prípad diskordancie pohlavia (0,09 %). U 255 vzoriek s fyziologickým karyotypom indikovaných k cytogenomickému vyšetreniu bolo zachytených celkom osem (7,21 %, n = 111) patologických variant metódou CMA. Metódou MLPA bolo z týchto ôsmich patogénnych variant zachytených päť (3,47 %, n = 144). Celkový záchyt patogénnych variant metódami MLPA a CMA vrátane konfirmačných vyšetrení patologického karyotypu je 14 (5,14 %) a 17 (6,25 %) (n = 272). Záchyt patologických variant v skupine s izolovanými poruchami bol nižší než v skupine s mnohopočetnými poruchami (5,08 vs. 21,42 %). Záver: Potvrdila sa vyššia úspešnosť záchytu patologických variant so zmenou v počte kópií, metódou CMA než MLPA.
Objective: Analysis of prenatal samples from 2015 to 2020. Comparison detection rates of clinically relevant variants by cytogenetic karyotype analysis and cytogenomic MLPA (Multiplex Ligation-Depent Probe Amplification) and microarray methods (CMA – chromosomal microarray). Material and method: 1,029 prenatal samples were analyzed by cytogenetic karyotyping (N = 1,029), cytogenomic methods – MLPA (N = 144) and CMA (N = 111). All unbalanced changes were confirmed by MLPA or CMA. Results: From the analyzed set of fetuses, after subtraction of aneuploidies – 107 (10.40%, N = 1,029), 22 structural aberrations (2.39%, N = 922) – nine unbalanced changes (0.98%), 10 balanced changes (1.08%), one case of unclear mosaicism (0.09%), one case of presence of a marker chromosome (0.09%) and one case of sex discordance (0.09%) – were detected by karyotype analysis. A total of eight (7.21%, N = 111) pathological variants were detected by CMA in 255 samples with physiological karyotype indicated for cytogenomic examination. Five (3.47%, N = 144) of eight pathogenic variants were detected by MLPA method. The total capture of pathogenic variants by MLPA and CMA methods was 14 (5.14%) and 17 (6.25%) (N = 272), including confirmatory pathological karyotype testing. Detection of pathological variants in the isolated disorders group was lower than in the multiple disorders group (5.08 vs. 21.42%). Conclusion: A higher success rate for the detection of pathological copy number variation variants by the microarray method than by the MLPA method was confirmed.
- MeSH
- Clinical Studies as Topic MeSH
- Humans MeSH
- Microarray Analysis methods MeSH
- Mosaicism MeSH
- Multiplex Polymerase Chain Reaction methods MeSH
- Fetus MeSH
- Prenatal Diagnosis * MeSH
- Pregnancy MeSH
- DNA Copy Number Variations MeSH
- Congenital Abnormalities * diagnosis genetics MeSH
- Check Tag
- Humans MeSH
- Pregnancy MeSH
- Female MeSH
The review presents an evaluation of the development of on-line, at-line and in-line sample treatment coupled with capillary and microchip electrophoresis over the last 10 years. In the first part, it describes different types of flow-gating interfaces (FGI) such as cross-FGI, coaxial-FGI, sheet-flow-FGI, and air-assisted-FGI and their fabrication using molding into polydimethylsiloxane and commercially available fittings. The second part deals with the coupling of capillary and microchip electrophoresis with microdialysis, solid-phase, liquid-phase, and membrane based extraction techniques. It mainly focuses on modern techniques such as extraction across supported liquid membrane, electroextraction, single drop microextraction, head space microextraction, and microdialysis with high spatial and temporal resolution. Finally, the design of sequential electrophoretic analysers and fabrication of SPE microcartridges with monolithic and molecularly imprinted polymeric sorbents are discussed. Applications include the monitoring of metabolites, neurotransmitters, peptides and proteins in body fluids and tissues to study processes in living organisms, as well as the monitoring of nutrients, minerals and waste compounds in food, natural and wastewater.
- MeSH
- Electrophoresis, Capillary methods MeSH
- Electrophoresis, Microchip * methods MeSH
- Microdialysis MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
