UV–Vis spectroscopy in non-destructive testing

Non-destructive testing (NDT) is an analysis technique used by industry to evaluate the properties of a material, component, structure, or system for characteristic differences or defects without causing damage to the original matrix. In this chapter, ultraviolet–visible (UV–Vis) spectroscopy or Spectrophotometry (UV–Vis) as an NDT tool is well described. As its name implies, UV–Vis quantifies the properties of samples in the UV–Vis wavelength ranges of light (typically 190–900/1100 nm) without destroying the matrix. Specifically, UV–Vis visible spectroscopy determines how much light of a given wavelength passes through a sample, and how much is absorbed. Such information can be diagnostic of molecular identity, concentration, structure, or activity, whether of organic species such as porphyrins, benzenes, and naphthalenes or of biomolecules like nucleic acids and proteins. Spectrophotometers can scan either fixed (i.e., predefined) or variable wavelengths, and come in both single- and double-beam configurations. Its simple operating system and robustness have enthralled the attention of users. Thus this technology is widely used in various applications especially in the environment, pharmaceutical, and agriculture. In this chapter, the principle, significant applications, and future potential of UV–Vis spectroscopy as an NDT tool will be well described.