Latest App Notes & Case Studies

Dioxin surrogates and VOC emissions online measurement

Pseudomonas elastase (LasB) is a key drug target in various chronic and intractable infections. A library of 160 potential, in-house synthesised, elastase inhibitors were screened using a fluorescence assay with the internally quenched substrate Abz-Ala-Gly-Leu-Ala-Nba. Enzymatic kinetic measurements were done on a FLUOstar OPTIMA and Km and Vmax values were calculated for each inhibitor using the MARS Data Analysis software.

The Oris™ Cell Migration Assays from Platypus offer certain advantages over traditional migration assays. Especially the TriCoated kits enable the researcher to test the effect of different extracellular matrix components like Collagen I or Fibronectin on migration. In this application note we show the real-time monitoring of cell migration using a POLARstar Omega from BMG LABTECH equipped with a CO2 gas vented system.

Here, we demonstrate the productivity gains possible with Xevo TQ-S for use in bioanalytical methods. Xevo TQ-S employs a unique RADAR functionality to collect data in the time scale of a narrow 1- to 2-second peak.

Two cell-based signaling assays from Invitrogen, Fluo-4 Direct™ Calcium Assay and Tango™-bla U2OS GPCR Assay, were performed on the PHERAstar FS HTS instrument. The PHERAstar FS has several unique features that enhance the performance of these assays including direct optic bottom reading, high resolution cell layer scanning, injection at the point of measurement and dual emission detection.

Bacteria can monitor and respond to changes to environmental conditions via a cell density process known as quorum sensing. Bacteria use this process to monitor their community by producing, detecting and responding to low molecular mass signal molecules, called autoinducers. Effects on quorum sensing were investigated by measuring growth and bioluminescence of Vibrio fischeri. The FLUOstar OPTIMA was utilized to measure absorbance and luminescence in parallel.

Functional screening of single cell clones was achieved using the HTRF® IP-One assay. The HTRF® assay from Cisbio proved to be a fast and reliable method to directly screen a large number of stable transfected single cell clones. Carbachol dose response curves with fresh cells from a growing culture and frozen instant cells showed similar results for EC50 and signal-to-blank values.

The alamarBlue® cell proliferation assay is based on a reducing environment that indicates metabolic active cells. Active cells are able to convert resazurin into the resorufin. Resazurin is blue and non-fluorescent whereas resorufin is red and highly fluorescent; therefore a fluorescent and a colorimetric detection are possible. This application notes focuses on the quantification of cell proliferation in a Human Osteoblast cell culture by measuring alamarBlue® fluorescence on the FLUOstar OPTIMA microplate reader.

A europium based time-resolved fluorescence cytotoxicity assay was used to study the loss of membrane integrity of target cells. For that cells are loaded with a fluorescence enhancing ligand that penetrates the cell membrane quickly and is hydrolized to form a hydrophilic ligand that is released from cells only after cytolysis. The data obtained with BMG LABTECH´s PHERAstar shows that estrogen dramatically reduces cell induced by natural killer cells.

High Throughput Screening (HTS) labs are required to screen ever-increasing numbers of compounds against an increasing number and variety of assay types. With a level of flexibility and adaptability unsurpassed in the world of automated systems, HighRes’ MicroStar™ is ideal. It meets not only today’s lab requirements; it also anticipates the easy exchange of today’s components with tomorrow’s technology.