Single cell analysis of neutrophils NETs by Microscopic LSPR imaging system

A simple microengraving cell monitoring method for neutrophil extracellular traps (NETs) released from single neutrophils has been realized using a polydimethylsiloxane (PDMS) microwell array (MWA) sheet on a plasmon chip platform. An imbalance between NETs formation and the succeeding degradation (NETosis) are considered associated with autoimmune disease and its pathogenesis. Thus, an alternative platform that can conduct monitoring of this activity on single cell level at minimum cost but with great sensitivity is greatly desired. The developed MWA plasmon chips allow single cell isolation of neutrophils from 150 μL suspension (6.0 × 105 cells/mL) with an efficiency of 36.3%; 105 microwells with single cell condition. To demonstrate the utility of the chip, trapped cells were incubated between 2 to 4 h after introducing with 100 nM phorbol 12- myristate 13-acetate (PMA) before measurement. Under observation using a hyperspectral imaging system that allows high-throughput screening, the neutrophils stimulated by PMA solution show a significant release of fibrils and NETs after 4 h, with observed maximum areas between 314–758 μm2. An average absorption peak wavelength shows a redshift of Δλ = 1.5 nm as neutrophils release NETs

Deskilled and Rapid Drug-Resistant Gene Detection by Centrifugal Force-Assisted Thermal Convection PCR Device

Here we report the improved Cyclo olefin polymer (COP) microfluidic chip and polymerase chain reaction (PCR) amplification system for point-of-care testing (POCT) in rapid detection of Carbapenem-resistant Enterobacteriaceae (CRE). The PCR solution and thermal cycling is controlled by the relative gravitational acceleration (7G) only and is expected to pose minimal problem in operation by non-expert users. Detection is based on identifying the presence of carbapenemase encoding gene through the corresponding fluorescence signal after amplification. For preliminary tests, the device has been demonstrated to detect blaIMP-6 from patients stool samples. From the prepared samples, 96.4 fg/µL was detected with good certainty within 15 min (~106 thermocycles,) which is significantly faster than the conventional culture plate method. Moreover, the device is expected to detect other target genes in parallel as determination of the presence of blaNDM-1 and blaOXA-23 from control samples has also been demonstrated. With the rising threat of drug-resistant bacteria in global healthcare, this technology can greatly aid the health sector by enabling the appropriate use of antibiotics, accelerating the treatment of carriers, and suppressing the spread

Characterization of silver (Ag) nanomaterials, synthesized by the horizontal vapor phase crystal (HVPC) growth technique, for antimicrobial purposes

Triangular silver nanoplates, of different orientations, and other nanostructures were successfully synthesized for antimicrobial purposes using the Horizontal Vapor Phase Crystal (HVPC) growth technique. The starting material for the synthesis was thirty-five (35) mg of 99.99 % pure silver powder. Varied growth temperatures (800 °C, 900 °C, 1000 °C, or 1100 °C) and growth times (4 hours, 6 hours, or 8 hours) at a fixed ramp time of 80 minutes were used as parameters in this study. Scanning Electron Microscope (SEM) and Energy Dispersive X-ray (EDX) were used on the grown nanomaterials to determine the structures and the elemental composition. The SEM micrographs, which was supported by the EDX analysis, showed that nanoparticles, triangular nanoplates, hexagonal nanoplates, nanowires, nanoribbons, nanorods, and nanocubes can be grown in the HVPC technique. Analyses of the various parameters revealed that silver nanostructures are formed in all four zones of the quartz tube. Optimum size and number of nanoplates, whether triangular or hexagonal, were best grown at a low growth temperature of 800°C and a short growth time (4 hours and/or 6 hours) at zones 1 and 2. Spherical nanoparticles were best grown at the end of zones 2 and 4. The desired size can be achieved by increasing the growth time regardless of the growth temperature. Nanowires and nanorods are best grown at a high growth temperature (1100°C) and a short growth time (4 hours). Also, odd structures such as bled triangular plates, re-adsorbed particles, flakes, and forming wires were found at zones 1 and 3. Analyses of data led to the conclusion that the mechanism for deposition, nucleation, and growth of silver nanomaterials followed the vapor-solid process. Deposition of particles was affected by the growth temperature. At 800°C and 900 °C, vaporization is believed to be slow that promoted growth of 2-dimensional nanostructures. At 1000 °C and 1100°C, vaporization is believed to be fast that promoted the growth of one-dimensional nanostructures. Heterogeneous nucleation is believed to be predominantly occurred in the process since the quartz tube acted as a substrate. However, homogenous nucleation could occur when there is a decrease in saturation level brought by deposition of particles or decrease in temperature. Spectral Imaging Microscope was further used to explain why some grown nanomaterials emit different color. Real-time images of nanoparticles with spherical structure exhibited twinkling effect which was due to localized surface plasmon resonance. The pour-plate technique was employed to test the antimicrobial potency of the grown silver nanomaterials. The number of colonies grown on a plate containing silver nanomaterials, a plate containing silver powder, and a plate that do not contain silver powder were compared. Results revealed that the number of E. coli colonies grown when 105 CFU/mL of bacterial solution was exposed to a quartz tube with silver nanomaterials was decreased compared to when it was exposed to a quartz tube with or without silver powde

SERS Active Hierarchical Nanopillar-huddle Array Fabricated via the Combination of Nanoimprint Lithography and Anodization

Metallic nanostructures and their fabrication methods have been studied for over decades as they are crucial in developing plasmonic sensing platforms. In this work, a hierarchical nanopillar huddle structure fabricated by thermal nanoimprint lithography with anodic porous alumina as template is presented. By utilizing this scheme, nanopillars (branches) rooted on regularly deployed substructures (footings) can be easily produced/reproduced for large working area at low-cost with high-throughput. After metal deposition for plasmon activation, tiny nanogaps were generated within each single huddle. The as-fabricated substrates are also tunable by varying the anodizing conditions and metal deposition material/thickness. Substrates produced using this scheme were evaluated by absorption spectra measurements and SERS detection of series of adsorbed molecules. Finite-difference time-domain (FDTD) simulation was conducted to validate the promising feature of the higher electric field energy density stimulated at the tiny nanogaps which resulted in a regular distribution of “hot-spots”. Finally, biosensing potentials were demonstrated by conducting measurements of four different nucleotides (i.e. AMP, CMP, TMP, GMP at 10−2 M) using silver sputtered substrate without any modification. Its SERS performance in the micron level was also evaluated via line-scan in two orthogonal direction in 10−2 M AMP solution

A computer based laboratory experiment on urbanization and land use using SPARK and My World GIS

The study focused on a computer based laboratory experiment that measures temperature variations over a small land area at De La Salle University - Manila campus. It identified general trends relating to land use and urbanization. The gathered observations can be used to recommend potential improvements that the university can undertake to moderate its own microclimate and optimize its land use. Data was collected using the SPARK Learning System and was mapped using My World GIS

Development of Liewik, academic software, for problem solving in physics

This research study was focused on the development of Liewik: Academic Software for Developing Problem Solving Skills that will improve the problem solving competencies of students and will serve as framework of software design. In this study, the development of Liewik followed the recommendations of various local and foreign Physics Education Researchers regarding problem solving in Physics and technology integration in education found as unpublished materials and retrieved from the World Wide Web. Moreover, suggestions regarding technical aspects from computer programmers were considered in the development of the running Liewik program. Evaluation shows that LIEWIK can be used for teaching and developing problem solving skills and may be used as model to develop the same for other lessons in Physics