Analytical chemistry application: Identification of Absorbance Peak and Removal of Background based on UV-Vis Spectral Data from SpectroWorks™

Analytical chemistry application: This Jupyter-notebook identifies absorbance peak from SpectroWorks™ data and removes background. The full-width half maximum at the absorbance peak is also given.

Challenge: We want to analyze a spectrum to obtain the peak wavelength absorption and the width of the peak, in a spectrum that contains background.

Solution: The following Jupyter notebook identifies the first peak and subsequently performs a background subtraction by fitting a curve to the background signal. The peak wavelength, absorption and peak width is then calculated.

UV-Vis spectrophotometry is a technique used to analyze the absorption of light by a sample at specific wavelengths in the ultraviolet and visible regions of the electromagnetic spectrum. One of the main applications of this technique is the identification and quantification of chemical compounds in a sample, this is frequently done by identifying peaks in the UV-Vis spectra. Peaks are characterized by their wavelength (λ) and their absorbance (A).

It is often necessary to remove the background signal from a UV-Vis spectrum. The background signal can arise from various sources, such as solvent absorption, scattering, or instrumental noise. Background correction is important to obtain accurate and reliable data, particularly when analyzing low concentrations of analytes.

One technique is background subtraction, which involves identifying a region of interest in the spectrum and fitting a curve to the background signal, then subtracting the fitted curve from the sample data.

In figure 1 and 2, we show an example of the output of this intuitive, easy-to-use Jupyter notebook.

Figure 1: An example of peak identification and background subtraction using sample data in the Jupyter notebook.

Figure 2: A table of all samples and the relevant information is automatically generated.