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Introduction: To compare the biomechanical parameters of microplates and the combined miniplate-microplate for fixing zygomaticomaxillary complex (ZMC) fractures using nonlinear finite element analysis (FEA). Material and Methods: Two samples of ZMC fracture models were prepared. In sample 1 (S1), the fractures were stabilized with microplates, and in sample 2 (S2), with miniplates plus microplates. FEA software was used to measure the displacement, Von Mises stress distribution (VMSD), and maximum principal stress distribution (MPSD). Results: The displacement was 6.7 μm in the L-shaped plate of both samples, 4.4 μm in the S1 lateral-edge plate, 4.8 μm in the S2 lateral-edge plate, 5.8 μm in the S1 bottom-edge plate, and 5.6 μm in the S2 bottom-edge plate. The VMSD was 41.1 MPa in the S1 lateral-edge plate, 24.3 MPa in the S2 lateral-edge plate, 7.6 MPa in the S1 Lshaped plate, 9.6 MPa in S2 L-shaped plate, 28.5 MPa in the S1 bottom-edge plate, and 11.8 MPa in the S2 bottom-edge plate. The MPSD was 46.2 MPa in the S1 lateral-edge plate, 26.4 MPa in the S2 lateral-edge plate, 3.6 MPa in S1 L-shaped plate, 4.2 MPa in S2 L-shaped plate, 30.9 MPa in S1 bottom-edge plate, and 14.1 MPa in the S2 bottom-edge plate. Conclusion: The L-shaped and lateral-edge plates in both samples had the highest and lowest amount of displacement, respectively. The lateral-edge plates in both samples had the highest VMSD and MPSD, which was higher in S1 than S2. The L-shaped plate had the lowest VMSD and MPSD in both samples. [ABSTRACT FROM AUTHOR]

Integer-order thermoviscoelastic models may fail to give an accurate description of the thermomechanical behavior of viscoelastic materials, which inherently have the memory-dependent feature. Meanwhile, with the miniaturization of devices, the small-scale effect on elastic deformation is becoming increasingly significant. To better describe the memory-dependent effect and the small-scale effect in viscoelastic microstructures, this work focuses on developing a refined nonlocal thermoviscoelastic model by incorporating the fractional-order dual-phase-lag (DPL) heat-conduction model and the fractional-order strain model. Moreover, the Caputo–Fabrizio (CF) definition and the Tempered-Caputo (TC) definition of the fractional derivative without a singular kernel as well as the extension of the Caputo definition are adopted to reflect the memory-dependent effects of the heat conduction and the stress–strain relation for the first time, respectively. Then, this new model is applied to investigate the transient response of a viscoelastic microplate subjected to a sinusoidal thermal loading. The governing equations involving the modified parameters are formulated and then solved by the Laplace-transform method. Some parametric results are demonstrated to display the impacts of the fractional-order parameter, the fractional-order strain parameter and the nonlocal parameter on the considered physical quantities. The results show that the nonlocal effect and the memory-dependent effect strongly depend on the viscoelastic microstructure characteristics in a thermal environment. [ABSTRACT FROM AUTHOR]

In this communication, it is mathematically proved that the modified couple stress theory-based stability trend (buckling-post-buckling) of the size-dependent porous functionally graded (metal-ceramic) shear deformable microplates with fully simply supported edges was wrongly predicted in the aforementioned paper. [ABSTRACT FROM AUTHOR]

The Sandell-Kolthoff (SK) assay is the main analytical method used to monitor population iodine nutrition in low- and middle-income countries. This assay can distinguish between populations that are iodine-deficient (median urinary iodine levels below 100 ppb), iodine-sufficient (median urinary iodine levels between 100 and 300 ppb), and iodine- excessive(median urinary iodine levels above 300 ppb). However, the analysis of urine samples with the SK reaction is technically challenging, partly because urine samples must be rigorously pretreated to remove interferents. In the literature, the only urinary metabolite that has been identified as an interferent is ascorbic acid. In this study, we used the microplate SK method to screen thirty-three of the major organic metabolites present in urine. We identified four previously unknown interferents: citric acid, cysteine, glycolic acid and urobilin. For each interferent, we investigated the following factors: (1) nature of interference–positive or negative, (2) threshold concentration for interference, and (3) possible mechanisms of interference. While this paper does not attempt to provide an exhaustive list of all interferents, knowledge of the main interferents allows for targeted removal. [ABSTRACT FROM AUTHOR]

ABSTRACT The application of fecal metaproteomics to large-scale studies of the gut microbiota requires high-throughput analysis and standardized experimental protocols. Although high-throughput protein cleanup and digestion methods are increasingly used in shotgun proteomics, no studies have yet critically compared such protocols using human fecal samples. In this study, human fecal protein extracts were processed using several different protocols based on three main approaches: filter-aided sample preparation (FASP), solid-phase-enhanced sample preparation (SP3), and suspension trapping (S-Trap). These protocols were applied in both low-throughput (i.e., microtube-based) and high-throughput (i.e., microplate-based) formats, and the final peptide mixtures were analyzed by liquid chromatography coupled to high-resolution tandem mass spectrometry. The FASP-based methods and the combination of SP3 with in-StageTips (iST) yielded the best results in terms of the number of peptides identified through a database search against gut microbiome and human sequences. The efficiency of protein digestion, the ability to preserve hydrophobic peptides and high molecular weight proteins, and the reproducibility of the methods were also evaluated for the different protocols. Other relevant variables, including interindividual variability of stool, duration of protocols, and total costs, were considered and discussed. In conclusion, the data presented here can significantly contribute to the optimization and standardization of sample preparation protocols in human fecal metaproteomics. Furthermore, the promising results obtained with the high-throughput methods are expected to encourage the development of automated workflows and their application to large-scale gut microbiome studies.IMPORTANCEFecal metaproteomics is an experimental approach that allows the investigation of gut microbial functions, which are involved in many different physiological and pathological processes. Standardization and automation of sample preparation protocols in fecal metaproteomics are essential for its application in large-scale studies. Here, we comparatively evaluated different methods, available also in a high-throughput format, enabling two key steps of the metaproteomics analytical workflow (namely, protein cleanup and digestion). The results of our study provide critical information that may be useful for the optimization of metaproteomics experimental pipelines and their implementation in laboratory automation systems.

AbstractIn this article, a novel size-dependent finite strip approach based on Carrera unified formulation (CUF) and micropolar elasticity is developed and introduced to investigate the free vibration analysis of micro-plate structures. The micropolar theory, through taking the micro-rotational degrees of freedom and micropolar couple stress effects into account, is a suitable elasticity theory for analysis of the microstructures. The finite strip method (FSM) allows for the division of a plate into some finite strips that are connected through the so-called nodal lines. The present higher-order refined finite strip model is more advanced and allows for the expression of all displacement and micro-rotation variables in each nodal line as a set of thickness functions that solely rely on the thickness coordinate, and the corresponding variable that depends on the in-plane coordinates, which involve continuously harmonic series and polynomial shape functions. Thanks to the CUF, the three-dimensional displacement and micro-rotation field are approximated compactly as a generic N-order expansion model. Therefore, the governing equations are obtained in terms of a few fundamental nuclei in a compact and explicit unified manner and presented here. The results obtained by the proposed method are compared with those available in the literature. [ABSTRACT FROM AUTHOR]

Tissue fibrosis is characterized by chronic fibroblast activation and consequently excessive accumulation of collagen-rich extracellular matrix. In vitro microplate-based assays are essential to investigate the underlying mechanism and the effect of antifibrotic drugs. In this study, in the absence of a gold-standard method, we optimized a simple, cost-effective, Sirius Red-based colorimetric measurement to determine the collagen production of fibroblasts grown on 96-well tissue culture plates. Based on our findings, the use of a serum-free medium is recommended to avoid aspecific signals, while ascorbate supplementation increases the collagen production of fibroblasts. The cell-associated collagens can be quantified by Sirius Red staining in acidic conditions followed by alkaline elution. Immature collagens can be precipitated from the culture medium by acidic Sirius Red solution, and after subsequent centrifugation and washing steps, their amount can be also measured. Increased attention has been paid to optimizing the assay procedure, including incubation time, temperature, and solution concentrations. The resulting assay shows high linearity and sensitivity and could serve as a useful tool in fibrosis-related basic research as well as in preclinical drug screening. [ABSTRACT FROM AUTHOR]

Mechano-bactericidal nanopillars represent a class of antibacterial surfaces that rely on nanoscale topographical features to inflict damage on attached bacteria. A potential application for mechano-bactericidal nanopillars is their use as self-cleaning antibacterial coatings for surfaces that are exposed to inadvertent splashes or cough droplets containing infectious bacteria. In this work, we prepared two types of zinc oxide nanopillars: nanopillars with an average width of 194 nm and an average spacing of 163 nm (referred to as low-surface-density nanopillars) and nanopillars with an average width of 88 nm and an average spacing of 91 nm (referred to as high-surface-density nanopillars). To assess their antibacterial capabilities, we deposited small aqueous droplets containing bioluminescent Pseudomonas aeruginosa onto the nanopillars and monitored the loss of the bioluminescence signal to quantify acute bacterial inactivation in real time. To investigate possible recovery of bacterial viability after acute inactivation, the nanopillars were submerged in nutrient-rich media and incubated for another 24 h, while the bioluminescence signal was monitored. Combining the results from bioluminescence monitoring with scanning electron microscopy, optical density measurements, and plate counting of colony-forming units after the recovery period, we found that nanopillars with an average width of 194 nm and an average spacing of 163 nm were indeed mechano-bactericidal and efficacy was dependent on the bacterial concentration within the droplets. Nanopillars with an average width of 88 nm and an average spacing of 91 nm were ineffective as bactericidal surfaces regardless of the bacterial concentration. This work further supports the use-case of mechano-bactericidal nanopillars as antibacterial coatings for dry surfaces and demonstrates bioluminescence monitoring as a promising tool to complement existing assessment techniques for mechano-bactericidal nanopillars as well as other antibacterial coatings. [ABSTRACT FROM AUTHOR]

Growth curve measurements are one of the fundamental operations in microbiology and molecular biology. Modern microplate readers have the advantage of high-throughput and ease of automation. This allows for real-time monitoring of many small bacterial cultures and a significant decrease labor and materials costs. Using these devices, tens to hundreds of absorbance readings can be collected simultaneously for hundreds of samples. The small volume and the geometry of a well from a microplate implies that calibration and comparative studies must be performed before switching from one cultivation and growth monitoring system to another. Here, Escherichia coli XL1 Blue was used as a reference strain in order to test the feasibility of using a common, filter-based microplate reader for recording growth curves when performing antibiotic and toxicity testing. Two different cultivation conditions (flask cultivation and microplate cultivation) and three inoculum/media ratios were tested. The recorded growth curves indicated that the growth of the bacteria is much slower, the turbidity levels are lower, and reading are more variable in the microplate compared with the Erlenmayer flask. Several major technical difficulties must be carefully dealt with when measuring bacterial growth curves in microplates: efficiency of oxygenation that leads to slow growth rates and low densities, condensation on the microplate lead that leads to interference and evaporation of the growth media. [ABSTRACT FROM AUTHOR]

CRISPR/Cas12-based biosensors are emerging tools for diagnostics. However, their application of heterogeneous formats needs the efficient detection of Cas12 activity. We investigated DNA probes attached to the microplate surface and cleaved by Cas12a. Single-stranded (ss) DNA probes (19 variants) and combined probes with double-stranded (ds) and ssDNA parts (eight variants) were compared. The cleavage efficiency of dsDNA-probes demonstrated a bell-shaped dependence on their length, with a cleavage maximum of 50%. On the other hand, the cleavage efficiency of ssDNA probes increased monotonously, reaching 70%. The most effective ssDNA probes were integrated with fluorescein, antibodies, and peroxidase conjugates as reporters for fluorescent, lateral flow, and chemiluminescent detection. Long ssDNA probes (120–145 nt) proved the best for detecting Cas12a trans-activity for all of the tested variants. We proposed a test system for the detection of the nucleocapsid (N) gene of SARS-CoV-2 based on Cas12 and the ssDNA-probe attached to the microplate surface; its fluorescent limit of detection was 0.86 nM. Being united with pre-amplification using recombinase polymerase, the system reached a detection limit of 0.01 fM, thus confirming the effectiveness of the chosen ssDNA probe for Cas12-based biosensors. [ABSTRACT FROM AUTHOR]

Growth curve measurements are fundamental operations in microbiology and molecular biology. Microplate readers have the advantage of high-throughput and automation. This allows for real-time monitoring of many bacterial cultures and a decrease in labor and costs. The volume and geometry of a well from a microplate imply that calibration and comparative studies must be performed before switching from one cultivation and growth monitoring system to another. Here, Escherichia coli XL1 Blue was used as a reference strain in order to test the feasibility of using a common, filter-based microplate reader for recording growth curves when performing antibiotic and toxicity testing.

Copyright of Bozok Veterinary Sciences is the property of Bozok Veterinary Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Firat Universitesi Sağlik Bilimleri Tip Dergisi is the property of Firat Universitesiu, Saglik Bilimleri Enstitusu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: In this paper, interactions of two critical components—axial internal stress and transverse pressure—of a microplate sensor have been investigated. Static and dynamic characteristics of an electrostatically actuated rectangular microplate have been investigated to understand the effects of axial internal stress and transverse pressure. Method: The microplates have been modelled using Kirchhoff's plate theory along with von Karman nonlinearity. Galerkin principle is used to derive the reduced order model of the governing partial differential equation of motion. Results: The effects of the simultaneous presence of internal stress and transverse pressure on pull-in parameters and resonance frequency characteristics have been computed. Two important features of microplate sensors—resonance frequency tunability due to applied DC voltage and stability of resonance frequency during variation of operating temperature—have also been computed. Conclusions: The investigation shows that the tunability of a microplate sensor increases in the presence of compressive axial internal stress, and the stability improves due to the presence of transverse pressure. [ABSTRACT FROM AUTHOR]

Tissue fibrosis is characterized by chronic fibroblast activation and consequently excessive accumulation of collagen-rich extracellular matrix. In vitro microplate-based assays are essential to investigate the underlying mechanism and the effect of antifibrotic drugs. In this study, in the absence of a gold-standard method, we optimized a simple, cost-effective, Sirius Red-based colorimetric measurement to determine the collagen production of fibroblasts grown on 96-well tissue culture plates. Based on our findings, the use of a serum-free medium is recommended to avoid aspecific signals, while ascorbate supplementation increases the collagen production of fibroblasts. The cell-associated collagens can be quantified by Sirius Red staining in acidic conditions followed by alkaline elution. Immature collagens can be precipitated from the culture medium by acidic Sirius Red solution, and after subsequent centrifugation and washing steps, their amount can be also measured. Increased attention has been paid to optimizing the assay procedure, including incubation time, temperature, and solution concentrations. The resulting assay shows high linearity and sensitivity and could serve as a useful tool in fibrosis-related basic research as well as in preclinical drug screening.

In this paper, we consider the uniqueness issue for the inverse problem of load identification in a nanoplate by dynamic measurements. Working in the framework of the strain gradient linear elasticity theory, we first deduce a Kirchhoff‐Love nanoplate model, and we analyze the well‐posedness of the equilibrium problem, clarifying the correct Neumann conditions on curved portions of the boundary. Our uniqueness result states that, given a transverse dynamic load ∑m=1Mgm(t)fm(x)$$ {\sum}_{m=1}^M{g}_m(t){f}_m(x) $$, where M≥1$$ M\ge 1 $$ and {gm(t)}m=1M$$ {\left\{{g}_m(t)\right\}}_{m=1}^M $$ are known time‐dependent functions, if the transverse displacement of the nanoplate is known in an open subset of its domain for any interval of time, then the spatial components {fm(x)}m=1M$$ {\left\{{f}_m(x)\right\}}_{m=1}^M $$ can be determined uniquely from the data. The proof is based on the spherical means method. The uniqueness result suggests a reconstruction technique to approximate the loads, as confirmed by a series of numerical simulations performed on a rectangular clamped nanoplate. [ABSTRACT FROM AUTHOR]

CRISPR/Cas12-based biosensors are emerging tools for diagnostics. However, their application of heterogeneous formats needs the efficient detection of Cas12 activity. We investigated DNA probes attached to the microplate surface and cleaved by Cas12a. Single-stranded (ss) DNA probes (19 variants) and combined probes with double-stranded (ds) and ssDNA parts (eight variants) were compared. The cleavage efficiency of dsDNA-probes demonstrated a bell-shaped dependence on their length, with a cleavage maximum of 50%. On the other hand, the cleavage efficiency of ssDNA probes increased monotonously, reaching 70%. The most effective ssDNA probes were integrated with fluorescein, antibodies, and peroxidase conjugates as reporters for fluorescent, lateral flow, and chemiluminescent detection. Long ssDNA probes (120–145 nt) proved the best for detecting Cas12a trans-activity for all of the tested variants. We proposed a test system for the detection of the nucleocapsid (N) gene of SARS-CoV-2 based on Cas12 and the ssDNA-probe attached to the microplate surface; its fluorescent limit of detection was 0.86 nM. Being united with pre-amplification using recombinase polymerase, the system reached a detection limit of 0.01 fM, thus confirming the effectiveness of the chosen ssDNA probe for Cas12-based biosensors.

In the current study, a novel fluorescence-based microplate methodology was introduced for the one-step determination of alfuzosin hydrochloride, with an assessment of the eco-friendliness of the two developed methods. The development of rapid analytical methods with high sensitivity, selectivity, and low cost is a growing trend. In this context, we propose two simple and rapid spectrofluorimetric methods for the quantitative analysis of alfuzosin in the form of active pharmaceutical ingredient, tablets, and urine samples. The first method relies on a direct assay of the native fluorescence of alfuzosin in water, whereas the second method exploits the quenching effect of alfuzosin on calcein dye for its assay at emission wavelengths of 390 and 520 nm, respectively. The obtained results showed high sensitivity with good linearity (> 0.999) over the concentration ranges of 0.75–12.5 and 10–1200 ng/mL, respectively. The eco-friendly features of the proposed methods were proven by greenness evaluation studies employing the National Environmental Methods Index, analytical Eco-scale score, and Green Analytical Procedure Index as three assessment tools. It was concluded that both methods are efficient analytical tools from a green perspective and are promptly applicable for the alfuzosin assay, while the first method demonstrated 10-fold higher sensitivity. In addition, ever-increasing miniaturization as handling large numbers of micro-volume samples simultaneously and reagents in the proposed methods have enabled them to be safer alternatives for rapid routine analysis in quality control units.

An inexpensive single-arm robot is widely utilized for recent laboratory automation solutions. The integration of a single-arm robot as a transfer system into a semi-automatic liquid dispenser without a transfer system can be realized as an inexpensive alternative to a fully automated liquid handling system. However, there has been no quantitative investigation of the positional accuracy of robot arms required to transfer microplates. In this study, we constructed a platform comprising aluminum frames and digital gauges to facilitate such measurements. We measured the position repeatability of a robot arm equipped with a custom-made finger by repeatedly transferring microplates. Further, the acceptable misalignment of plate transfer was evaluated by adding an artificial offset to the microplate position using this platform. The results of these experiments are expected to serve as benchmarks for the selection of robot arms for laboratory automation in biology. Furthermore, all information for replicating this device will be made publicly available, thereby allowing many researchers to collaborate and accumulate knowledge, hopefully contributing to advances in this field., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Shipping of in vitro micro-cuttings in tubes or jars is a frequently used method as the plants are more likely to quickly reproduce and comply with quarantine regulations in plant germplasm distribution. However, these containers are fragile during transportation. To diminish the risk associated with the long-distance shipping of in vitro plants, a safe and widely applicable packing and conservation technique based on microplate and slow growth was developed in this study. Potato cultivar ZHB and ginger cultivar G-2 were used to optimize the system with microplates (96 wells), vacuum-sealed packaging, and slow-growth techniques. Under regular culture conditions, packing in vacuum-sealed microplates reduced the survival of ZHB and G-2 micro-cuttings to 85.8% and 20.0%, respectively, and regeneration to 61.8% and 0%, respectively. Reducing the temperature to 10 °C maintained the survival of ZHB and G-2 micro-cuttings in the range of 83.3–100% after 60 days. Exposure to darkness decreased the survival of G-2 and inhibited regrowth. Thus, conservation in darkness at 10 °C is suggested. The effects of iron concentration and plant growth retardants were further assessed. The addition of 1/4 MS medium combined with 100 mg/L chlormequat chloride (CCC) resulted in full survival and growth inhibition of plantlets, without malformation identified. Finally, incubation with 1/4 MS medium supplemented with 100 mg/L CCC in vacuum-sealed microplates at 10 °C in the dark resulted in high survival and suppressed germination. Sweet potato HXS was incubated as well to test the broad-spectrum applications of the technique; 100% survival and 6.7% germination was gained. Morphological indices of released cuttings recovered to control levels after two cycles of subculture in MS medium. A 0.1–0.2% genetic variation was detected by SSR and ISSR, suggesting genetic stability of the conserved samples. Finally, micro-cuttings were safely transported to cities located thousands of kilometers away without package and sample damage. Our results enable easy distribution of in vitro plant germplasms. [ABSTRACT FROM AUTHOR]

Routine cell culture reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) gene expression analysis is limited in scalability due to minimum sample requirement and multistep isolation procedures. In this study, we aimed to optimize and apply a cost-effective and rapid protocol for directly sampling gene expression data from microplate cell cultures. The optimized protocol involves direct lysis of microplate well population followed by a reduced thermocycler reaction time one-step RT-qPCR assay. In applications for inflammation and stress-induced cell-based models, the direct lysis RT-qPCR microplate assay was utilized to detect IFN1 and PPP1R15A expression by poly(I:C) treated primary fibroblast cultures, IL6 expression by poly(I:C) iPSC-derived astrocytes, and differential PPP1R15A expression by ER-stressed vanishing white-matter disease patient induced pluripotent stem cell (iPSC)-derived astrocytes. In application for neural differentiation medium recipe optimizations, conditions were screened for SYN1 and VGLUT1 in neuronal cultures, and S100B, GFAP and EAAT1 in astrocyte cultures. The protocol provides microplate gene expression results from cell lysate to readout within ~35 min, with comparable cost to routine RT-qPCR, and it may be utilized to support laboratory cell-based assays in basic and applied scientific and medical fields of research including stem-cell differentiation, cell physiology, and drug mechanism studies. [ABSTRACT FROM AUTHOR]

[Display omitted] • Offshore data support a clockwise rotation of the Falkland Islands Microplate. • Regional structural correlations suggest a Middle-Upper Jurassic timing of rotation of the microplate. • Structural analysis suggests that fast-changing stress configurations preceded the SW Gondwana fragmentation. Commonly, intra-continental wrenching is associated with a high degree of crustal faulting and fragmentation. The resulting continental blocks can undergo vertical-axis rotations, which in turn can lead to the generation of intricate fault networks within and along their boundary regions. Investigations into these structural complexities can support understanding of when and how these continental blocks rotate, and what their position was prior to transform margin formation. In the case of the Falkland Islands Microplate (part of the Falkland Plateau transform margin), its position between South Africa, South America, and East Antarctica prior to the break-up of Gondwana is still debatable. This uncertainty affects the reliability of plate models for this region. Here we integrate gravity and 2D and 3D seismic reflection data from the eastern margin of the microplate (west side of the Falkland Plateau Basin) to provide insights into the tectono-stratigraphic architecture of this area from Jurassic onwards, and into the evolution of the Falkland Islands Microplate. Our findings show that the western part of the Falkland Plateau Basin is an integral part of the microplate, and it underwent deformation in a relatively fast-changing stress regime. Stress field configuration estimates across the Falkland Islands Microplate support an alternation between a NE-SW and NW-SE/WNW-ESE orientation of σ 3 during the Jurassic and an ENE-WSW oriented σ 3 during the Lower Cretaceous. Correlations of this local stress configuration with the regional support a Middle to Upper Jurassic rotation of the microplate in a predominantly extensional setting facilitated by the early fragmentation of south-western Gondwana. [ABSTRACT FROM AUTHOR]

Abstract Objective Microplates are ubiquitous in biological research because they make it easy to collect data for hundreds of different conditions in a single experiment. Despite this, there is no standard method to annotate the wealth of data contained in each plate. Results We introduce a new file format, called wellmap, for describing the layout of wells on microplates. The format is text-based and emphasizes being easy to read, write, and share. It is capable of describing any layout for any experiment. It is also accompanied by a tool for generating clear visualizations of layout files, and a simple API for parsing layout files in analysis scripts written in python or R. We have used wellmap in our own research to annotate data from a wide variety of experiments, including qPCR and flow cytometry. Given the large number of experiments that make use of microplates, it is our hope that other researchers will find this file format as useful as we have. For complete instructions on how to install and use wellmap, visit: https://wellmap.rtfd.io .

Ensuring the safety and high quality of food relies on promptly and clearly identifying foodborne diseases, including Salmonella. Nucleic acid testing plays an important role in ensuring food safety. Commercially available high-throughput molecular extraction technologies in-field application is limited as they are reliant on specialized and expensive equipment. The 96-well microplate recycling through biopolymer inner surface coating, was confirmed with FTIR, XRD, and XPS. Once optimized the DNA extraction protocol was equipment-free, user and eco-friendly while reducing sample contamination. Using the biopolymer microplate, the extraction and direct LAMP amplification of Salmonella spp. from milk samples were assessed. The gDNA had an average 260/280 ratio of 1.97, with a DNA yield of 16.88 ± 5.40 μg mL−1 from 9 × 1010 CFU mL−1 Salmonella. Subsequently, using acid chrome K we visually detected the presence of Salmonella. The quantity of bacteria was correlated to the increase in the blue intensity of the color indicator. A detection limit of 1.54 CFU mL−1 was achieved with good specificity and sensitivity in an equipment free setting. This study successfully established a 96-well plate-based high-throughput equipment free DNA extraction method. The methods enable the high-throughput extraction and amplification of 96 samples concomitantly within 1hr 30 min corresponding respectively to a total of 1536 and 768 samples within a working day treated by a researcher without the use of specialized and expensive equipment. The polymeric modified microplate was used for high-throughput DNA extraction and direct molecular amplification for pathogen detection. High-throughput DNA extraction no longer requires cumbersome equipment. • Green user-friendly recycling of the microplate for DNA extraction and amplification. • Microplate repurposed as a high-throughput, pH responsive DNA purification surface. • Application for the DNA extraction and LAMP detection of Salmonella in milk. • High-throughput daily extraction and amplification of 1536 and 768 samples respectively. • Polymeric plate yields 16.88 ± 5.40 μg mL−1 and a detection limit of 1.54 CFU mL−1. [ABSTRACT FROM AUTHOR]

• Buckling and post-buckling of microplates under localized heating is assessed. • Analytical expressions for pre-buckling stresses are developed using Airy's stress function. • The plate is modelled using Reddy's TSDT and von Kármán geometric nonlinearity. • The small-scale effects are included using the modified strain gradient theory. • Governing equation of motion are derived using the Galerkin's method. The semi-analytical framework is developed for in-plane thermal stresses within the microplates under localized heating. Localized heating is modelled using Fourier Series expansions over the complete domain of the plate. These stresses within the plate are estimated after solving the in-plane thermoelasticity problem using Airy's stress approach. Utilizing these stresses, present work also studies the buckling and post-buckling behaviour of a porous metal foam microplate resting on Winkler and Pasternak elastic foundations. The plate is modelled using Reddy's third-order shear deformation theory (TSDT) and von Kármán geometric nonlinearity, and the size-dependent effects are included using the modified strain gradient theory (MSGT). Galerkin's weighted residual method converts the partial differential equations (PDEs) into algebraic equations. The post-buckling equilibrium path is obtained using the modified Newton-Raphson method. The mode shapes of the microplate for the various configurations of the plate with different boundary conditions due to localized thermal loading are plotted. Also, these mode shapes are compared with the mode shapes of the microplate due to in-plane mechanical loading. The parametric effect of porosity, elastic foundation parameters, thickness of plate, size of plate, boundary conditions and loading concentrations on the buckling and post-buckling behaviour of the plate is studied. [ABSTRACT FROM AUTHOR]

Algal polysaccharides exhibit a wide range of biological activities and potential applications. Many of these bioactivities correlate positively with the presence of sulfate groups on the polysaccharides. The most common method used for sulfate quantification in algal samples is the turbidimetric method using the barium chloride-gelatin reagent. However, the original procedure is difficult to adapt for routine analysis since it is laborious and time-consuming. An optimized method was established using 96-well microplates, with the advantage of reducing waste and discrimination between organic and inorganic sulfates. This proposed method produced the same accuracy as the original.

Unravelling how reactive oxygen species regulate fundamental biological processes is hampered by the lack of an accessible microplate technique to quantify target-specific protein thiol redox state in percentages and moles. To meet this unmet need, we present RedoxiFluor. RedoxiFluor uses two spectrally distinct thiol-reactive fluorescent conjugated reporters, a capture antibody, detector antibody and a standard curve to quantify target-specific protein thiol redox state in relative percentage and molar terms. RedoxiFluor can operate in global mode to assess the redox state of the bulk thiol proteome and can simultaneously assess the redox state of multiple targets in array mode. Extensive proof-of-principle experiments robustly validate the assay principle and the value of each RedoxiFluor mode in diverse biological contexts. In particular, array mode RedoxiFluor shows that the response of redox-regulated phosphatases to lipopolysaccharide (LPS) differs in human monocytes. Specifically, LPS increased PP2A-, SHP1-, PTP1B-, and CD45-specific reversible thiol oxidation without changing the redox state of calcineurin, PTEN, and SHP2. The relative percentage and molar terms are interpretationally useful and define the most complete and extensive microplate redox analysis achieved to date. RedoxiFluor is a new antibody technology with the power to quantify relative target-specific protein thiol redox state in percentages and moles relative to the bulk thiol proteome and selected other targets in a widely accessible, simple and easily implementable microplate format. • RedoxiFluor is an accessible, simple, and easily implementable microplate technique. • RedoxiFluor measures relative target-specific redox state in percentage and moles. • RedoxiFluor can contextualise findings by measuring bulk thiol proteome redox state. • In array mode, RedoxiFluor can screen multiple targets in parallel. • RedoxiFluor can be used to advance knowledge of protein thiol redox biology. [ABSTRACT FROM AUTHOR]

In the present work, the equations of motion of a thin orthotropic nanoplate were obtained based on the new modified couple stress theory and the third-order shear deformation plate theory. The nanoplate was considered as a size-dependent orthotropic plate. The governing equations were derived using the dynamic version of Hamilton’s principle and natural boundary conditions were formulated. An analytical solution in the form of a double Fourier series was obtained for a simply supported rectangular nanoplate. The eigenvalue problem was set and solved. It was analytically shown that the displacements of the median surface points in the plane of the plate do not depend on the material length scale parameters in the same directions; these in-plane directional displacements depend on the material length scale parameter in the out-of-plane direction only. On the other hand, the out-of-plane directional displacement depends on the length scale parameter in the plane directions only. The cross-section rotation angles depend on all length scale parameters. It was shown that the size-dependent parameters only have a noticeable effect on the deformed state of the plate if their order is not less than the order (plate height)-1.

Based on the modified couple stress theory (MCST) and the quasi-3D sinusoidal shear deformation theory (SSDT), size-dependent mechanical buckling and free vibration analyses of microplates reinforced by functionally graded graphene nanoplatelets (FG-GNPs) are studied in this paper. The composite microplate is considered to be composed of epoxy reinforced by GNPs distributed along the thickness direction based on various symmetric and non-symmetric patterns. Effective material properties of the composite microplate are estimated based on the Halpin-Tsai model along with the rule of mixture and the set of governing equations are derived using Hamilton's principle. An exact solution is presented for simply supported microplates using Navier's method and effect of various parameters including aspect ratio and thickness of the microplate, material length scale parameter and width, thickness, total mass fraction and distribution of GNPs on the critical buckling load and natural frequencies are investigated. [ABSTRACT FROM AUTHOR]

In the present work, the equations of motion of a thin orthotropic nanoplate were obtained based on the new modified couple stress theory and the third-order shear deformation plate theory. The nanoplate was considered as a size-dependent orthotropic plate. The governing equations were derived using the dynamic version of Hamilton's principle and natural boundary conditions were formulated. An analytical solution in the form of a double Fourier series was obtained for a simply supported rectangular nanoplate. The eigenvalue problem was set and solved. It was analytically shown that the displacements of the median surface points in the plane of the plate do not depend on the material length scale parameters in the same directions; these in-plane directional displacements depend on the material length scale parameter in the out-of-plane direction only. On the other hand, the out-of-plane directional displacement depends on the length scale parameter in the plane directions only. The cross-section rotation angles depend on all length scale parameters. It was shown that the size-dependent parameters only have a noticeable effect on the deformed state of the plate if their order is not less than the order (plate height)-1. [ABSTRACT FROM AUTHOR]

Oceanic plates are growing through narrow boundaries, such as mid-ocean ridges and transform faults. However, the discovery of diffuse plate boundary suggests another type of plate boundary that accommodates difference in plate motion via internal deformation. Along the Central and Southeast Indian ridges, for example, the Capricorn and Macquarie microplates exhibit widespread diffuse boundaries and hence divide the Indo-Australian Plate further into the Indian, Australian, Capricorn, and Macquarie plates. As for microplates distributed along the East Pacific Rise and Pacific-Antarctic Ridge in the Pacific Ocean, however, the typical plate boundaries surrounding the given microplate are distinctly established. Global plate reorganization involving the changes in plate motion or in spreading direction can be accommodated by forming a microplate through ridge extinction, ridge propagation, and pseudofault formation. However, relations between these tectonic processes have not been quantitatively assessed. In particular, we aim to examine tectonic constrains on the formation processes of microplates with diffuse plate boundary. In this study, we compare plate size, plate age, full-spreading rates, thermal structures, total rotation, and rotation rate for the 9 microplates including extinct plates (i.e., Capricorn, Macquarie, and Mammerickx* microplates in the Indian and Southern Oceans; Galapagos, Easter, Juan Fernandez, Bauer*, Friday*, and Selkirk* microplates in the Pacific Ocean; extinct plates are denoted with asterisks). From this comparison, we find that the microplate formation would require certain tectonic conditions (e.g., full-spreading rates faster than 70–80 mm/yr and rotation rates faster than 5–6°/m.y.) to evolve into an independent and rigid plate with respect to the neighboring plates. If the conditions are not met, the same tectonic reorganization would result in a microplate with diffuse plate boundaries. [ABSTRACT FROM AUTHOR]

The East African Rift (EAR) is a typical site for the study of dynamic processes leading to continental break-up and dislocation. In the context of global plate motion models, the kinematics of EAR system is less well defined. In this study, the analysis of repeated GPS geodetic data represents a quantum leap in accuracy that allows us to reassess the recent kinematics of EAR. Our results show that the Somali plate rotates at a velocity of 0.076°/m in the Nubian fixed reference frame the velocity increasing from south to north. We also found that the seismotectonic parameters of both sets of plate boundaries are embodied by lithospheric thinning and oceanic accretion, including a scissor-shaped opening. Normal faults are active along a series of fissure boundaries. This NubianSomalian divergence across the East African rift system implies a redistribution of deformation and stress regulation along rift segments connecting rigid blocks that allows for the heterogeneity of the East African basement. We also note the presence of very high-risk seismic zones.

The application of fecal metaproteomics to large-scale studies of the gut microbiota requires high-throughput analysis and standardized experimental protocols. Although high-throughput protein cleanup and digestion methods are increasingly used in shotgun proteomics, no studies have yet critically compared such protocols using human fecal samples. In this study, human fecal protein extracts were processed using several different protocols based on three main approaches: filter-aided sample preparation (FASP), solid-phase-enhanced sample preparation (SP3), and suspension trapping (S-Trap). These protocols were applied in both low-throughput (i.e., microtube-based) and high-throughput (i.e., microplate-based) formats, and the final peptide mixtures were analyzed by liquid chromatography coupled to high-resolution tandem mass spectrometry. The FASP-based methods and the combination of SP3 with in-StageTips (iST) yielded the best results in terms of the number of peptides identified through a database search against gut microbiome and human sequences. The efficiency of protein digestion, the ability to preserve hydrophobic peptides and high molecular weight proteins, and the reproducibility of the methods were also evaluated for the different protocols. Other relevant variables, including interindividual variability of stool, duration of protocols, and total costs, were considered and discussed. In conclusion, the data presented here can significantly contribute to the optimization and standardization of sample preparation protocols in human fecal metaproteomics. Furthermore, the promising results obtained with the high-throughput methods are expected to encourage the development of automated workflows and their application to large-scale gut microbiome studies.IMPORTANCEFecal metaproteomics is an experimental approach that allows the investigation of gut microbial functions, which are involved in many different physiological and pathological processes. Standardization and automation of sample preparation protocols in fecal metaproteomics are essential for its application in large-scale studies. Here, we comparatively evaluated different methods, available also in a high-throughput format, enabling two key steps of the metaproteomics analytical workflow (namely, protein cleanup and digestion). The results of our study provide critical information that may be useful for the optimization of metaproteomics experimental pipelines and their implementation in laboratory automation systems., Competing Interests: The authors declare no conflict of interest.

Here we present a versatile system for milliliter-scale perfusion culture of adherent cells that can be built using basic tools, based on a readily available one-well culture plate (84 cm2 culture area). Media composition and flow paths can be programmatically controlled via USB serial interface using the FETbox hardware controller and associated PlateFlo Python package. The FETbox can control up to five high current 12 V devices such as common pinch valves, solenoids, and DC motor peristaltic pumps. It was designed to be easily customized with built-in accommodation for additional electronic components (e.g. analog sensors and input), use of the ubiquitous Arduino Nano platform, and easily expanded serial communication protocol. Multiple FETboxes can be used in parallel for additional devices. Applications of the PlateFlo system include perfusion culture of laboratory experiments requiring large cell numbers including genome-scale genetic screens and proteomics, as well as novel perfusion schemes including dynamic media conditions and sequential cell culture.

Objective: Microplates are ubiquitous in biological research because they make it easy to collect data for hundreds of different conditions in a single experiment. Despite this, there is no standard method to annotate the wealth of data contained in each plate. Results: We introduce a new file format, called wellmap, for describing the layout of wells on microplates. The format is text-based and emphasizes being easy to read, write, and share. It is capable of describing any layout for any experiment. It is also accompanied by a tool for generating clear visualizations of layout files, and a simple API for parsing layout files in analysis scripts written in python or R. We have used wellmap in our own research to annotate data from a wide variety of experiments, including qPCR and flow cytometry. Given the large number of experiments that make use of microplates, it is our hope that other researchers will find this file format as useful as we have. For complete instructions on how to install and use wellmap, visit: https://wellmap.rtfd.io. [ABSTRACT FROM AUTHOR]

Measurement of proteasome activity is fast becoming a commonly used assay in many laboratories. The most common method to measure proteasome activity involves measuring the release of fluorescent tags from peptide substrates in black microplates. Comparisons of black plates used for measuring fluorescence with different properties show that the microplate properties significantly affect the measured activities of the proteasome. The microplate that gave the highest reading of trypsin-like activity of the purified 20S proteasome gave the lowest reading of chymotrypsin-like activity of the 20S proteasome. Plates with medium binding surfaces from two different companies showed an approximately 2-fold difference in caspase-like activity for purified 20S proteasomes. Even standard curves generated using free 7-amino-4-methylcoumarin (AMC) were affected by the microplate used. As such, significantly different proteasome activities, as measured in nmol AMC released/mg/min, were obtained for purified 20S proteasomes as well as crude heart and liver samples when using different microplates. The naturally occurring molecule betulinic acid activated the chymotrypsin-like proteasome activity in three different plates but did not affect the proteasome activity in the nonbinding surface microplate. These findings suggest that the type of proteasome activity being measured and sample type are important when selecting a microplate.

Shipping of in vitro micro-cuttings in tubes or jars is a frequently used method as the plants are more likely to quickly reproduce and comply with quarantine regulations in plant germplasm distribution. However, these containers are fragile during transportation. To diminish the risk associated with the long-distance shipping of in vitro plants, a safe and widely applicable packing and conservation technique based on microplate and slow growth was developed in this study. Potato cultivar ZHB and ginger cultivar G-2 were used to optimize the system with microplates (96 wells), vacuum-sealed packaging, and slow-growth techniques. Under regular culture conditions, packing in vacuum-sealed microplates reduced the survival of ZHB and G-2 micro-cuttings to 85.8% and 20.0%, respectively, and regeneration to 61.8% and 0%, respectively. Reducing the temperature to 10 °C maintained the survival of ZHB and G-2 micro-cuttings in the range of 83.3–100% after 60 days. Exposure to darkness decreased the survival of G-2 and inhibited regrowth. Thus, conservation in darkness at 10 °C is suggested. The effects of iron concentration and plant growth retardants were further assessed. The addition of 1/4 MS medium combined with 100 mg/L chlormequat chloride (CCC) resulted in full survival and growth inhibition of plantlets, without malformation identified. Finally, incubation with 1/4 MS medium supplemented with 100 mg/L CCC in vacuum-sealed microplates at 10 °C in the dark resulted in high survival and suppressed germination. Sweet potato HXS was incubated as well to test the broad-spectrum applications of the technique; 100% survival and 6.7% germination was gained. Morphological indices of released cuttings recovered to control levels after two cycles of subculture in MS medium. A 0.1–0.2% genetic variation was detected by SSR and ISSR, suggesting genetic stability of the conserved samples. Finally, micro-cuttings were safely transported to cities located thousands of kilometers away without package and sample damage. Our results enable easy distribution of in vitro plant germplasms.

Routine cell culture reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) gene expression analysis is limited in scalability due to minimum sample requirement and multistep isolation procedures. In this study, we aimed to optimize and apply a cost-effective and rapid protocol for directly sampling gene expression data from microplate cell cultures. The optimized protocol involves direct lysis of microplate well population followed by a reduced thermocycler reaction time one-step RT-qPCR assay. In applications for inflammation and stress-induced cell-based models, the direct lysis RT-qPCR microplate assay was utilized to detect IFN1 and PPP1R15A expression by poly(I:C) treated primary fibroblast cultures, IL6 expression by poly(I:C) iPSC-derived astrocytes, and differential PPP1R15A expression by ER-stressed vanishing white-matter disease patient induced pluripotent stem cell (iPSC)-derived astrocytes. In application for neural differentiation medium recipe optimizations, conditions were screened for SYN1 and VGLUT1 in neuronal cultures, and S100B, GFAP and EAAT1 in astrocyte cultures. The protocol provides microplate gene expression results from cell lysate to readout within ~35 min, with comparable cost to routine RT-qPCR, and it may be utilized to support laboratory cell-based assays in basic and applied scientific and medical fields of research including stem-cell differentiation, cell physiology, and drug mechanism studies.

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The immobilization of sensing bioreceptors is a critical feature affecting the final performance of a biosensor. For DNA detection, the (strept)avidin-biotin affinity interaction is often used for the immobilization of biotin-labeled oligonucleotides or PCR amplicons. Herein, DNA binding proteins are proposed as alternative universal anchors for both DNA immobilization and detection, based on the strong and specific affinity interaction between certain DNA binding proteins and their respective dsDNA binding sites. These binding sites can be incorporated in the target DNA molecule during synthesis and by PCR, eliminating the need for post-synthesis chemical modification and resulting in lower costs. When scCro DNA binding protein was immobilized on microplates and nitrocellulose membrane, both ssDNA and dsDNA targets were successfully detected. The detection limits achieved were similar to those obtained with the streptavidin-biotin system. However, the scCro system resulted in higher signals while using less amount of protein. The adsorption properties of scCro were superior to streptavidin's, making scCro a viable alternative as an anchor biomolecule for the development of DNA assays and biosensors. Finally, a nucleic acid lateral flow assay based solely on two different DNA binding proteins, scCro and dHP, was developed for the detection of a PCR amplicon. Overall, the proposed system appears to be very promising and with potential use for multiplex detection using various DNA binding proteins with different sequence specificities. Further work is required to better understand the adsorption properties of these biomolecules on nitrocellulose, optimize the assays comprehensively, and achieve improved sensitivities. [ABSTRACT FROM AUTHOR]

This research concentrates on pull-in behavior of a micro-plate laminated with a novel material: light activated shape memory polymer (LASMP). Under light exposure, this material can realize dynamic Young's modulus. With this feature, a LASMP laminated micro-plate model considering micro-scale effect and geometric nonlinearity is proposed. Dynamic equations of the micro-plate system are derived via Hamilton principle and solved by Galerkin method whose accuracy is validated by FEM. Effect of size dependency and dynamic Young's modulus of LASMP on pull-in behavior of the micro-plate are studied. Present study provided a technique to manipulate pull-in phenomenon of electrically actuated micro-plate. [ABSTRACT FROM AUTHOR]

The lack of reproducibility of published studies is one of the major issues facing the scientific community, and the field of biofilm microbiology has been no exception. One effective strategy against this multifaceted problem is the use of minimum information guidelines. This strategy provides a guide for authors and reviewers on the necessary information that a manuscript should include for the experiments in a study to be clearly interpreted and independently reproduced. As a result of several discussions between international groups working in the area of biofilms, we present a guideline for the spectrophotometric and fluorometric assessment of biofilm formation in microplates. This guideline has been divided into 5 main sections, each presenting a comprehensive set of recommendations. The intention of the minimum information guideline is to improve the quality of scientific communication that will augment interlaboratory reproducibility in biofilm microplate assays.

Premise Phosphorus (P) is an essential macronutrient that is often limited in agricultural systems. Determining inorganic phosphate (Pi) contents of plant tissues is crucial for evaluating plant P status. Here, we present a simple, high‐throughput colorimetric microplate technique to measure Pi contents in rice (Oryza sativa) leaf tissues, based on the molybdenum blue reaction. Methods and Results We used a hole puncher to sample small equal areas of leaf tissue for Pi extraction. We removed the leaf grinding and weighing steps, which are time‐consuming and normally required to release Pi from the tissues and to measure the biomass for data normalization, respectively. We showed that the punching method yielded comparable results to the conventional grinding method for two rice cultivars grown under various levels of P supply. Conclusions Compared with existing techniques, this protocol is more suited to an initial screening, enabling one researcher to determine the Pi contents of thousands of rice leaf samples within a few hours.

Premise: Phosphorus (P) is an essential macronutrient that is often limited in agricultural systems. Determining inorganic phosphate (Pi) contents of plant tissues is crucial for evaluating plant P status. Here, we present a simple, high‐throughput colorimetric microplate technique to measure Pi contents in rice (Oryza sativa) leaf tissues, based on the molybdenum blue reaction. Methods and Results: We used a hole puncher to sample small equal areas of leaf tissue for Pi extraction. We removed the leaf grinding and weighing steps, which are time‐consuming and normally required to release Pi from the tissues and to measure the biomass for data normalization, respectively. We showed that the punching method yielded comparable results to the conventional grinding method for two rice cultivars grown under various levels of P supply. Conclusions: Compared with existing techniques, this protocol is more suited to an initial screening, enabling one researcher to determine the Pi contents of thousands of rice leaf samples within a few hours. [ABSTRACT FROM AUTHOR]

Purpose: Here, first experiences with a prototype tool for high throughput (passive) permeability profiling, a 96-well plate comprising the Permeapad® membrane, are reported. The permeabilities of a set of drugs were determined and compared to published measures of oral absorption, such as human fraction absorbed (Fa) and in vitro permeability values obtained using other tools. Methods: The tool consists of a 96-well bottom and screen plate with the artificial, phospholipid-based barrier (Permeapad®) mounted between the plates' lower and upper compartments. The permeability of 14 model compounds including high- and low-absorption drugs, cationic, anionic, zwitterionic and neutral molecules, was determined by quantifying the compounds' transport over time, deriving the steady-state flux from the linear part of the cumulative curves and calculating the apparent permeability (Papp). The membrane structure was investigated in a high-resolution digital light microscope. Results: The Permeapad® 96-well plate was found suited to distinguish high and low absorption drugs and yielded a hyperbolic correlation to Fa. The Papp values obtained were congruent with those determined with in-house prepared Permeapad® in the Franz cell set-up. Furthermore, good to excellent correlations were seen with Caco-2 permeability (R2 = 0.70) and PAMPA permeability (R2 = 0.89). Microscopic investigation of the Permeapad® barrier revealed the formation of phospholipid vesicles and myelin figures in aqueous environment. Conclusion: The Permeapad® 96-well plate permeation set-up is a promising new tool for rapid and reproducible passive permeability profiling. [ABSTRACT FROM AUTHOR]

Adamantane drugs (e.g., memantine, rimantadine, and amantadine) consist of a core tricyclodecane with different substituents. Memantine is used for treatment of Alzheimer's disease, while rimantadine and amantadine are recommended for influenza A infection. Additionally, amantadine is clinically used for Parkinson's disease. Analysis of adamantine drugs by optical detection requires some derivatization due to the lack of chromophores or fluorophores in their structures. This procedure is performed to enhance their detectability, but it can be time- and labor-intensive. This work focuses on developments of a simple and fast technique for the analysis of these drugs in a microplate platform. Derivatization was achieved in 50 mM borate buffer (pH 11.0) using a stoichiometric ratio between the analyte and fluorescamine (as a derivatizing reagent) of 1:10 and a reaction time of 10 min. The fluorescent derivatives were determined in a 96-well microplate using excitation and emission wavelengths at 385 and 485 nm, respectively. The method showed good linearity (r2 > 0.968), repeatability (RSDs of < 2.6%), and accuracy (% recovery 96.2–101.1 with RSD < 4.5%) with acceptable limits of detection (< 3 µM) and quantitation (< 10 µM). The method was successfully applied for the determination of the drugs in pharmaceutical formulations. [ABSTRACT FROM AUTHOR]