Articles by Caitlin Smith

  • Take Your Samples Around the World in an Environmental Test Chamber

    Monday, February 17, 2014
    Did you ever wonder just how would your dependable lab equipment—or your smartphone, for that matter—function in, say, Antarctica? Or even just blocks from your home or lab? How long would your smartphone or tablet last if it were accidentally left outside, braving the elements for days at a time?
  • Particle Sizing Systems: Key to QC and Product Testing

    Thursday, September 05, 2013
    A particle size analyzer, also known as a particle sizer, is used to measure the sizes of particles in a sample. It can also determine distributions of particle sizes.
  • UHPLC: Pushing the Limits of HPLC

    Friday, August 09, 2013
    For fields that rely on liquid chromatography, the standard today is usually ultra high-performance liquid chromatography (UHPLC). And with good reason—compared to its chromatography predecessors, UHPLC is faster, provides better separation, and requires less reagents for operation. A steady evolution of new instrument models over the past 10 years means that today you can find a UHPLC system with a variety of features to support your lab’s work. Below are some basic guidelines for the range of UHPLC instruments available today, as well as purchasing considerations.
  • Thermal Cyclers: Behind the Technology

    Wednesday, July 03, 2013
    Thermal cyclers, also known as PCR machines or thermocyclers, are essential for any laboratory that relies on molecular biology. An indispensable tool for DNA amplification, the thermal cycler often becomes a nonstop workhorse that lab workers expect to function properly and efficiently.
  • Analytical and Preparative Ultracentrifuges

    Wednesday, April 24, 2013
    Ultracentrifuges are a type of centrifuge designed to rotate samples at “ultrahigh” speeds (much higher than conventional centrifuges), with a rotational speed of up to 150,000 rpm, creating a centrifugal force up to more than 1 million × g. All centrifuges can separate species within a liquid according to density, but the high centrifugal acceleration of ultracentrifuges lets you focus in on those tiny differences among molecules like proteins or nucleic acids.
  • Capillary Electrophoresis Systems for High-Resolution Separations

    Thursday, March 21, 2013
    Capillary electrophoresis (CE) systems are powerful instruments that can separate proteins, nucleic acids, or other species from a mixture quickly, with great accuracy and a relatively small investment of researcher time. CE and its cousin, gel electrophoresis, both separate molecules according to charge and size, sometimes referred to as a molecule’s electrophoretic mobility.
  • Guide to Solid Phase Extraction Systems

    Monday, February 18, 2013
    Solid phase extraction (SPE) is a liquid chromatography method of separating a particular compound, or analyte, from a liquid mixture in which it is dissolved or suspended. This is commonly performed when separating an analyte of interest from other impurities in a mixture, for example, in order to use the resulting sample (now more concentrated, and with greater purity) for further analytical or quantitative studies such as mass spectrometry.
  • Buyers’ Guide: Flow Cytometers

    Friday, February 15, 2013
    The ability to sort individual cells quickly based on their size or protein expression has had a significant, positive impact on any area of cell biology research or medicine in which a mixed population of cells needs to be sorted out. This is accomplished using flow cytometry, in which cells (or particles) in suspension are funneled single-file through a narrow opening that ends in a nozzle, such that droplets of fluid emerge one at a time. Each droplet may, or may not, contain one cell.
  • Overview of X-Ray Diffraction Systems

    Friday, January 04, 2013
    X-ray diffraction—analyzing the diffraction patterns that result when a beam of X-rays scatters off of atoms in a crystal structure—is a powerful tool for studying molecular structure. Analyzing the specific angles of the diffracted X-rays, as well as their intensities, allows scientists to ascertain the size and shape of the molecules in the crystal, the atoms within those molecules, and their spatial arrangements and bonds. X-ray diffraction is valuable in many fields, having been used to determine molecular structures for the design of therapeutic drugs, and to understand the bonds and folds in three-dimensional protein structures. X-ray diffraction is also important for the structural analysis of many types of molecules, thin film analysis, examining crystal phase and structure, and sample stress and strain.
  • Guide to Micromanipulators

    Wednesday, November 14, 2012
    Micromanipulators are devices intended to translate macroscopic movements of the human hand into microscopic movements of a fine tool held in its grasp.
  • Guide to Potentiometric and Karl Fischer Titrators

    Thursday, September 06, 2012
    Titration is the process of determining the concentration of a chemical substance in a sample.
  • Laminar Flow Hoods and Biological Safety Cabinets

    Monday, June 11, 2012
    Laminar flow hoods fall in to two basic categories: biological safety cabinets (or biosafety cabinets) and laminar flow clean benches. These categories differ in the level of protection provided to the user, the sample, and the environment. Laminar flow h
  • Benchtop Basics: Tips for Buying pH Meters and Balances

    Thursday, April 26, 2012
    Most laboratories would grind to a halt without the fundamental measurements provided by electrochemistry and weighing instruments.