scholarly journals Lossless Immunocytochemistry using Photo-polymerized Hydrogel Thin-films

2020 ◽  
Author(s):  
Jeong Hyun Lee ◽  
Aline T. Santoso ◽  
Emily S. Park ◽  
Kerryn Matthews ◽  
Simon P. Duffy ◽  
...  
Keyword(s):  
Thin Film ◽  
Cell Loss ◽  
Microtiter Plate ◽  
Bottom Surface ◽  
Biological Technique ◽  
Centrifugation Step ◽  
Cell Sample ◽  
Diagnostic Applications ◽  
Rare Cells ◽  
Time Required

AbstractImmunocytochemistry (ICC), or immunofluorescence microscopy, is an essential biological technique for phenotyping cells in both research and diagnostic applications. Standard ICC methods often do not work well when the cell sample contains a small number of cells (<10,000) because of the significant cell loss that occurs during washing, staining, and centrifugation steps. Cell loss is particularly relevant when working with rare cells, such as circulating tumor cells, where such losses could significantly bias experimental outcomes. In order to eliminate cell loss in ICC protocols, we present a method to encapsulate the cell sample in a photo-polymerized hydrogel thin-film. The hydrogel thin-film is permeable to antibodies and other ICC reagents, thereby allowing the use of standard ICC protocols without modification. The cell sample is physically constrained by the hydrogel at the bottom surface of a standard (unmodified) imaging microtiter plate, thereby enabling the acquisition of high-quality micrographs regardless of the properties of the cell sample or staining reagents. Furthermore, while standard ICC requires several centrifugation steps during staining and washing, our hydrogel encapsulation method requires only a single centrifugation step. This property greatly reduces the time required to perform ICC protocols and is more compatible with robotic platforms. In this study, we show that standard ICC and Cytospin protocols are extremely lossy (>70% loss) when the sample contains less than 10,000 cells, while encapsulating the cells using a permeable hydrogel thin-film results in a lossless ICC process.

Evaluation of a Bead-based Enzyme Immunoassay for the Rapid Detection of Osteocalcin in Human Serum

2000 ◽  
Vol 46 (2) ◽  
pp. 252-257 ◽  
Author(s):  
Alexandra M Crăciun ◽  
Cees Vermeer ◽  
Hans-Georg Eisenwiener ◽  
Norbert Drees ◽  
Marjo H J Knapen
Keyword(s):  
Human Serum ◽  
Microtiter Plate ◽  
Lower Detection Limit ◽  
Unknown Sample ◽  
Linear Dose ◽  
Human Volunteers ◽  
Lower Detection ◽  
Routine Clinical Setting ◽  
Commercial Kits ◽  
Time Required

Abstract Background: Circulating osteocalcin is a well-known marker for bone formation, but none of the commercial kits currently available can be used in automated systems. Here we present the first semiautomated assay for human serum osteocalcin. Methods: Polystyrene beads were coated with antibodies against the COOH terminus of osteocalcin and used in the COBAS® EIA System. Osteocalcin was detected with peroxidase-conjugated antibodies against the osteocalcin NH2 terminus. Results: The time required to analyze an unknown sample was 60 min, with a lower detection limit of 4.5 μg/L and a linear dose–response curve between 4.5 and 100 μg/L. The intraassay imprecision (CV) was 5–8% (n = 21); the interassay variation was 6–9% (n = 14). In samples from human volunteers and patients, data generated with the newly developed assay were comparable to those obtained with standard microtiter plate-based assays. Conclusions: The coated beads assay may be implemented on fully automated analyzers, which not only may further reduce imprecision but may also substantially increase the applicability of osteocalcin as a marker for bone metabolism in the routine clinical setting.

scholarly journals Evaluation of Microalgae’s Plastic Biodeterioration Property by a Consortium of Chlorella sp. and Cyanobacteria sp.

2021 ◽  
Vol 77 (3) ◽  
pp. 86-98
Author(s):  
Prakash Bhuyar ◽  
Sathyavathi Sundararaju ◽  
Ho Xuan Feng ◽  
Mohd Hasbi Ab. Rahim ◽  
Sudhakar Muniyasamy ◽  
...  
Keyword(s):  
Polymer Degradation ◽  
Low Density ◽  
Dsc Analysis ◽  
Initial Composition ◽  
Edx Analysis ◽  
Chlorella Sp ◽  
Research Article ◽  
Biological Technique ◽  
Time Required ◽  
Oxygen Ratio

Malaysia is one of the top eight countries that has a drawback of mismanaged plastic waste. This study intended to investigate polymer degradation using the biological technique with the help of microalgae to minimise the time required for biodegradation. This research article aims to identify the collected sample with the most suitable microalgae for the biodegradation of microplastic and to analyse the biodegradation of the polymer by microalgae. The results revealed that the consortium of Chlorella sp. and Cyanobacteria sp. were able to deteriorate low-density polyethene (LDPE sample) through several stages, and this was confirmed by UV-Spec, FESEM, EDX, CHNO, FTIR and DSC analysis. The results obtained revealed that microalgae producing exopolysaccharides (EPS) decreased the carbon and oxygen ratio. According to SEM micrographs, microalga may colonise, agglomerate, and adhere microplastics to its surface, regardless of its fractional size. The EDX analysis showed that the initial composition of carbon was 92.30 ± 1.23 %, while after the incubation, the carbon composition started decreasing from 53.18 % to 39.12 ± 1.08 %. Finally, there was a 37.91 % decrease in carbon weight from elemental analysise

Comprehensive light trapping study of next generation thin film solar cells

2011 ◽  
Vol 1303 ◽  
Author(s):  
Zhou Zhou ◽  
Jian Zhou ◽  
Xiaowei Sun ◽  
Tim Cheng ◽  
Shengqi Wang ◽  
...  
Keyword(s):  
Thin Film ◽  
Solar Cells ◽  
Light Trapping ◽  
Solar Spectrum ◽  
Front Surface ◽  
Thin Film Solar Cells ◽  
Bottom Surface ◽  
Next Generation ◽  
Long Wavelength ◽  
Trapping Effects

ABSTRACTLight trapping is one of the key challenges for the next generation of thin film solar cells. In this work, we have identified the distinct light trapping effects for short and long wavelength solar spectrum ranges, by investigating lighting trapping structures on both sides of Si thin film solar cells. The sub-wavelength moth-eye-like photonic front surface and multi-layer grating photonic crystal reflector on the bottom surface are studied in detail via the Finite Difference Time Domain method for its solar energy absorption characteristics. Our study reveals the drastic difference in the light trapping effects within the solar spectrum wavelength. This work may provide guidance for efficiency enhancement of next generation thin film photovoltaic cells.

Enhancement of light trapping for thin film solar cells

MRS Advances ◽  
2018 ◽  
Vol 4 (13) ◽  
pp. 743-748
Author(s):  
Yasha Yi ◽  
Wei Guo ◽  
Yueheng Peng
Keyword(s):  
Thin Film ◽  
Solar Cells ◽  
Light Trapping ◽  
Solar Spectrum ◽  
Front Surface ◽  
Thin Film Solar Cells ◽  
Bottom Surface ◽  
Next Generation ◽  
Long Wavelength ◽  
Trapping Effects

ABSTRACTLight trapping is one of the key challenges for next generation thin film solar cells. In this work, we have identified the distinct light trapping effects for short and long wavelength solar spectrum range, by investigating lighting trapping structures on both sides of Si thin film solar cells. The sub-wavelength photonic front surface by wet etching and multi-layer photonic crystal reflector on the bottom surface are studied in detail for its solar energy absorption characteristics. Our study reveals the drastic difference of the light trapping effects within the solar spectrum wavelength. This work may provide guidance for the efficiency enhancementfor next generation thin film photovoltaic cells.

GreenLight™ Model 960

2013 ◽  
Vol 96 (2) ◽  
pp. 369-385 ◽  
Author(s):  
Richard Fernandes ◽  
Conn Carey ◽  
James Hynes ◽  
Dmitri Papkovsky
Keyword(s):  
Oxygen Consumption ◽  
High Throughput ◽  
Bacterial Load ◽  
Test Sample ◽  
Microtiter Plate ◽  
Viable Count ◽  
Microbial Load ◽  
High Throughput Method ◽  
Contamination Levels ◽  
Time Required

Abstract The importance of food safety has resulted in a demand for a more rapid, high-throughput method for total viable count (TVC). The industry standard for TVC determination (ISO 4833:2003) is widely used but presents users with some drawbacks. The method is materials- and labor-intensive, requiring multiple agar plates per sample. More importantly, the method is slow, with 72 h typically required for a definitive result. Luxcel Biosciences has developed the GreenLight™ Model 960, a microtiter plate-based assay providing a rapid high-throughput method of aerobic bacterial load assessment through analysis of microbial oxygen consumption. Results are generated in 1–12 h, depending on microbial load. The mix and measure procedure allows rapid detection of microbial oxygen consumption and equates oxygen consumption to microbial load (CFU/g), providing a simple, sensitive means of assessing the microbial contamination levels in foods (1). As bacteria in the test sample grow and respire, they deplete O2, which is detected as an increase in the GreenLight probe signal above the baseline level (2). The time required to reach this increase in signal can be used to calculate the CFU/g of the original sample, based on a predetermined calibration. The higher the initial microbial load, the earlier this threshold is reached (1).

scholarly journals Magnetic-Based Enrichment of Rare Cells from High Concentrated Blood Samples

Cancers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 933 ◽  
Author(s):  
Junhao Wu ◽  
Katharina Raba ◽  
Rosa Guglielmi ◽  
Bianca Behrens ◽  
Guus Van Dalum ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Magnetic Beads ◽  
Mononuclear Cells ◽  
Fluorescent Microscopy ◽  
Cost Effective ◽  
Cell Loss ◽  
Magnetic Bead ◽  
Immunofluorescence Staining ◽  
Peripheral Blood Mononuclear ◽  
Rare Cells

Here, we tested two magnetic-bead based systems for the enrichment and detection of rare tumor cells in concentrated blood products. For that, the defined numbers of cells from three pancreatic cancer cell lines were spiked in 108 peripheral blood mononuclear cells (PBMNCs) concentrated in 1 mL, mimicking diagnostic leukapheresis (DLA) samples, and samples were processed for circulating tumor cells (CTC) enrichment with the IsoFlux or the KingFisher systems, using different types of magnetic beads from the respective technology providers. Beads were conjugated with different anti-EpCAM and MUC-1 antibodies. Recovered cells were enumerated and documented by fluorescent microscopy. For the IsoFlux system, best performance was obtained with IsoFlux CTC enrichment kit, but these beads compromised the subsequent immunofluorescence staining. For the KingFisher system, best recoveries were obtained using Dynabeads Biotin Binder beads. These beads also allowed one to capture CTCs with different antibodies and the subsequent immunofluorescence staining. KingFisher instrument allowed a single and streamlined protocol for the enrichment and staining of CTCs that further prevented cell loss at the enrichment/staining interface. Both IsoFlux and KingFisher systems allowed the enrichment of cell line cells from the mimicked-DLA samples. However, in this particular experimental setting, the recovery rates obtained with the KingFisher system were globally higher, the system was more cost-effective, and it allowed higher throughput.

Modification of Thin Film Growth using Glancing-Angle Ions

1999 ◽  
Vol 585 ◽  
Author(s):  
Scott A. Barnett ◽  
Kurt C. Ruthe ◽  
Paul M. Deluca
Keyword(s):  
Thin Film ◽  
Film Growth ◽  
Thin Film Growth ◽  
Ion Energy ◽  
Glancing Angle ◽  
Gaas Films ◽  
Minimal Damage ◽  
Clean Contaminated ◽  
Time Required ◽  
Step Flow Growth

AbstractThis paper reviews the use of glancing-angle ions for modifying surfaces and thin film growth processes. Ions impinging on a flat surface at oblique incidence angles are mostly reflected without penetrating, providing very low sputtering rates along with minimal damage and implantation. They also provide a unique selectivity, where ion energy is coupled to defects or rough portions of the surface, while flat portions are essentially unaffected. This allows one to clean contaminated surfaces and smoothen rough surfaces, with little or no ion damage. In addition, recent results indicate that the ion energy couples directly to adatoms during epitaxial growth of GaAs(001). This was observed by a decrease in the time required for diffusion across terraces on a vicinal GaAs surface, as the glancing-angle Ar ion current was increased. It was also found that ion-enhanced diffusion shifted the growth mode from two-dimensional island nucleation to step-flow growth, and resulted in flatter growth surfaces. Finally, glancing-angleions can be used to introduce biaxial texture into polycrystalline GaAs films.

Robotic chromatography: development and evaluation of automated instrumentation for assay of glycohemoglobin

1993 ◽  
Vol 39 (1) ◽  
pp. 143-147 ◽  
Author(s):  
C D Herold ◽  
K Andree ◽  
D A Herold ◽  
R A Felder
Keyword(s):  
High Performance ◽  
Labor Cost ◽  
Microtiter Plate ◽  
Sample Collection ◽  
Liquid Chromatograph ◽  
Hands On ◽  
Collection Tube ◽  
Boronate Affinity Chromatography ◽  
Time Required ◽  
And Control

Abstract The measurement of glycohemoglobin (GHb) by boronate affinity chromatography is useful in monitoring long-term glucose control in diabetic subjects. The inherent disadvantage of this method is the hands-on time required because the hemoglobin fractions are separated on individual disposable columns. To overcome this disadvantage, we have programmed a Hamilton Microlab 2200 automated pipetting cartesian robot to complete the procedure, from the aspiration of blood from the sample-collection tube to the transfer of the separated hemoglobin fractions to a microtiter plate for absorbance measurement. This automated robotic system can analyze 96 specimens, including patients' samples and control material, in approximately 3 h. The precision (CV) of the method ranged from 1.6% to 3.5% within-run and from 2.7% to 3.5% day-to-day. The results correlated with those obtained with the Accuflex semiautomated robot, which used the identical disposable column, and those obtained with a Primus high-performance liquid chromatograph, which used a regenerated microparticle column. Automation of the GHb procedure allowed improved throughput, reduced labor cost, improved precision, and offered greater laboratory safety.

Effect of Annealing Temperature on the Structure of Al-Hf Films

1977 ◽  
Vol 35 ◽  
pp. 280-281
Author(s):  
P. J. Smith ◽  
J. K. Howard
Keyword(s):  
Thin Film ◽  
Annealing Temperature ◽  
Thick Layer ◽  
Atomic Ratio ◽  
Film Structure ◽  
Grain Structure ◽  
Bottom Surface ◽  
Fine Grained ◽  
Continuous Layer ◽  
Layer 2

The Al-Hf reaction is important because of the electromigration properties of Al-Hf thin-film conductors and because of the possible effect of the reaction on the barrier height of Hf Schottky barrier diodes (1). Previous studies of Al-Hf films had shown that the final structure was dependent on the grain structure of the A1 layer (2). When Hf was in contact with a largegrained A1 layer, Al3Hf formed as precipitates at A1 grain boundaries; when Hf was in contact with a fine-grained A1 layer, a continuous layer of Al3Hf formed at the Al-Hf interface. In the present work we show that, by varying the importance of A1 diffusion through Hf relative to Hf diffusion through Al, the annealing temperature influences both the overall film structure and the Al-Hf atomic ratio at the bottom surface. A 6000-Å-thick layer of Al was deposited on 1000 Å of Hf;

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