Alkaline agarose gels are used chiefly to measure the size of first and second strands of cDNA (Construction of cDNA Libraries Stage 1: Synthesis of First-strand cDNA Catalyzed by Reverse Transcriptase) and to analyze the size of the DNA strand after digestion of DNA-RNA hybrids with nucleases such as S1. - [Read Alkaline Agarose Gel Electrophoresis Protocol]
Protocol allows you to measure the content of cyclic adenosine 3',5'-monophosphate (cyclic AMP or cAMP) in splenic B lymphocytes (B cells) in an enzyme-linked immunoassay. This protocol utilizes acetylation of cAMP to improve sensitivity and reduce interference. Protocol includes information on: how to determine cAMP, calculations and reagents and materials. - [Read Assay of Cyclic AMP in Lysates of Cells]
The CellTiter-Glo® Luminescent Cell Viability Assay is a homogeneous method to determine the number of viable cells in culture. Detection is based on using the luciferase reaction to measure the amount of ATP from viable cells. The amount of ATP in cells correlates with cell viability. - [Read Cell Viability Assays that Measure ATP Protocol]
The CellTiter-Blue® Cell Viability Assay uses an optimized reagent containing resazurin. The homogeneous procedure involves adding the reagent directly to cells in culture at a recommended ratio of 20µl of reagent to 100µl of culture medium. - [Read Cell Viability Assays that Measure Metabolic Capacity Protocol]
Choosing a cell viability or cytotoxicity assay from among the many different options available can be a challenging task. Includes information on: Establishing an In Vitro Model System; Choosing an Endpoint to Measure; Characterizing Assay Responsiveness; Determining Dose and Duration of Exposure; Homogeneous Assays for Multiwell Formats and Automated Screening; Additional Factors to Consider When Choosing a Cell Viability Assay; Cell Viability Assays that Measure ATP Protocol; etc.. - [Read Cell Viability Information For Protocols and Applications]
Direct method for determining efficiency in yeast. The plating efficiency of a strain is a measure of the percentage of cells in a culture that are capable of forming colonies (colony forming . - [Read Determining Plating Efficiency in Yeast: Direct Method]
The cyclooxygenase (COX) reaction can be monitored by measurement of oxygen consumption, peroxidase co-substrate oxidation or prostaglandin (PG) detection. This protocol describes a procedure measuring cyclooxygenase activity by quantifying PGE2 produced by enzymatic conversion of arachidonic acid, in the presence or absence of potential inhibitors. - [Read ELISA Method to Measure Inhibition of the COX Enzymes Protocol]
Flow cytometry is a widely used method for characterizing and separating individual cells. This basic protocol focuses on: measure fluorescence intensity produced by fluorescent-labled antibodies and ligands that bind specific cell-associated molecules. Includes: Immunofluorescence Staining and Flow Cytometry Analysis. - [Read Flow Cytometry Analysis Protocol]
Flow cytometry is a widely used method for characterizing and separating individual cells. This basic protocol focuses on: measure fluorescence intensity produced by fluorescent-labled antibodies and ligands that bind specific cell-associated molecules. Includes: Immunofluorescence Staining; Flow Cytometry Analysis. - [Read Flow Cytometry Analysis Protocol]
Protocol describes the quantitation of DNA using Hoechst 33258, a fluorescent dye that binds to double-stranded DNA. Fluorometry is simple and more sensitive than spectrophotometry, and allows the detection of nanogram quantities of DNA. The assay can only be used to measure the concentration of DNAs whose sizes exceed ~1 kb, as Hoechst 33258 binds poorly to smaller DNA fragments. - [Read Fluorometric Quantitation of DNA Using Hoechst 33258 Protocol]
This method measures the leakage of DNA and lactate dehydrogenase from lymphocytes into the surrounding medium as an indicator of cytotoxicity. This method also includes an assay of intracellular (mitochondrial) diaphorase as a measure of cellular activity (MTT assay). - [Read Human Lymphocyte Cytotoxicity Assay Protocol]
ImageJ - Image Processing and Analysis in Java. Useful program for MacOs MacosX and PC. Analysis includes: Measure area, mean, standard deviation, min and max of selection or entire image. Measure lengths and angles. Use real world measurement units s - [Read ImageJ - Image Processing and Analysis in Java]
Assess T cell activation protocol - measure T cell proliferation upon in vitro stimulation of T cells via antigen or agonistic antibodies to TCR. eBioscience - [Read In Vitro T Cell Activation]
This assay is used to measure cell viability. It is a two-color fluorescence assay that simultaneously determines: Live cell number and Dead cell number. - [Read Live Dead Assay for Cell Viability Protocol]
The more commonly available single-laser cytometers can also be used to measure multicellular conjugates, but due to overlaps in emission spectra, the extent of labeling cells with fluorophores must be controlled much more carefully when the single-laser machines are used. This protocol describes the labeling of cells and analysis of conjugates with either dual-laser or single laser flow cytometers. - [Read Measurement of Intercellular Conjugates by Flow Cytometry Protocol]
Describes flow cytometric protocols using the dyes Indo-1 AM, Fluo-3, and Fura Red AM to measure intracellular calcium concentration. Support protocols detail the use of calcium buffers to calibrate a flow cytometric calcium assay, and methods to facilitate dye loading; an alternate protocol describes the use of a spectrofluorimeter to measure intracellular calcium for those investigators without access to a flow cytometer. - [Read Measurement of Intracellular Ions by Flow Cytometry Protocol]
The latest generation of Promega cell-based assays includes luminescent and fluorescent chemistries to measure markers of cell viability, cytotoxicity and apoptosis, as well as to perform reporter analysis. Using these tools researchers can investigate how cells respond to growth factors, cytokines, hormones, mitogens, radiation, effectors, compound libraries and other signaling molecules. The protocols provided are guidelines for multiplexing cell-based assays & are intended as starting points. - [Read Multiplexing Cell Viability Assays Protocols]
NIH Image. Image can be used to measure area, mean, centroid, perimeter, etc. of user defined regions of interest. It also performs automated particle analysis and provides tools for measuring path lengths and angles. Spatial calibration is supported to p - [Read NIH Image for Mac]
This protocol focuses on the interactions between L-selectin expressed on neutrophils and PNAd coated onto the plastic surface. The main purpose of the flow chamber assay is to visualize and measure interactions between flowing cells expressing a given adhesion molecule on their surface, and their receptor, either directly coated on the flow chamber lower wall or expressed on a cell monolayer. - [Read Protocol for L-selectin-PNAd Interactions under Flow Conditions.]
Unlike spherical phage, such as T4 and λ, which have roughly equal weight ratios of protein to DNA, filamentous phage have about six times more protein than DNA; the protein therefore contributes substantially to the absorption spectrum.