In this short overview, we consider cases for diffuse reflection spectroscopy and introduce the Kubelka-Munk diffuse reflectance formula. We conclude by comparing diffuse transmittance, diffuse reflectance, logarithmic transforms of both, and the Kubelka-Munk transform for mid-infrared spectroscopy of the same sample.
Förster resonance energy transfer (FRET) is a versatile part of the toolbox of fluorescence methods. This through-space, photon-less energy transfer process between a donor fluorophore and an acceptor chromophore is perhaps most famous for its utility as a “molecular ruler” that can resolve nanometer-scale distances. FRET is also a popular and advantageous basis for biomolecular assays and sensors.
This tutorial explains the most critical components of the sample introduction system of modern ICP-optical emission spectroscopy (OES) and ICP-mass spectrometry (MS) instruments, providing analysts with a guide for initial configuration settings and recommended maintenance intervals for reliable daily operation.
Inductively coupled plasma mass spectrometry (ICP-MS) instruments can perform low-level elemental analysis in a wide range of sample types, from high-purity chemicals to high matrix digests. But achieving consistently low detection limits requires good control of elemental contamination, as well as spectral interferences. A clean working area, careful selection of reagents, and good sample handling techniques are key to successful trace and ultratrace elemental analysis. In this article, we provide five practical tips for controlling contaminants and minimizing detection limits.
Spectroscopy offers a range of available techniques that can be differentiated by the use or omission of reference spectra.
The physics and chemistry of the phenomenon have been well known for many years, and this knowledge can tell us how self-absorption can be not only “corrected,” but also tuned to our advantage in analytical applications of LIBS.
Seven common mistakes in the analysis of Raman spectra can lead to overestimating the performance of a model.
How to create trouble-free sample preparation workflow for elemental analysis.
Help for handling sample-specific concerns in spectrofluorometry.
In the second part of a three-part series, instrument-specific concerns that require modifications to reproduce fluorescence spectra accurately are addressed.
Analysts using fluorescence emission and fluorescence excitation spectroscopy may encounter several common problems in their measurements. This tutorial, the first of a three-part series, provides a procedure to help avoid them.
Reliable quantitative FT-IR measurements require that the pathlength be known to within 1%. Pathlength estimations based on nominal spacer thickness are not reliable and require that the actual pathlength be measured for accurate data. We demonstrate how.
SERS offers many advantages. However, there are several issues to be aware of when trying to use SERS signals in analytical applications.
Total reflection X-ray fluorescence (TXRF) spectroscopy offers impressive performance, providing ultratrace elemental analysis with detection limits reaching the femtogram levels. Here, we provide a tutorial on the technique and the key steps that users should follow.
Contrary to popular belief, neither good “spike” recoveries nor the use of the method of standard additions (MSA) will guarantee accurate results in ICP-OES.
Master the art of selecting analytical wavelengths for ICP-OES with these essential steps and enhance your results.
In the third installment of this tutorial, the authors discuss the determination of the isotopic composition of a sample from a mass spectrometric measurement.
In the second installment of this tutorial, the authors explain the instrumentation for measuring naturally occurring stable isotopes, specifically the magnetic sector mass spectrometer.
The second installment of this two-part series illustrates further technical principles and applications of the most common mass analyzers used in bioanalytical laboratories today, as well as novel techniques and mass analyzer designs. Examples are based upon the authors' research in small molecule applications.
