An ultraviolet spectroscope (UV Spectroscope) is an analytical instrument that utilizes the interaction between ultraviolet light (typically in the wavelength range of 200–400 nm) and matter. It is primarily used to study the absorption, emission, or reflection characteristics of substances, thereby inferring information about their composition, concentration, or structure. The following are its key points:

Working Principle

1. Spectroscopic System: Uses a prism or grating to decompose ultraviolet light into monochromatic light.

2. Sample Interaction: The light beam passes through the sample, and certain wavelengths are absorbed due to electronic transitions in molecules (e.g., π→π*, n→π* transitions).

3. Detection and Analysis: A detector records the absorption spectrum, with different substances exhibiting unique absorption peaks at specific wavelengths (e.g., proteins at 280 nm, nucleic acids at 260 nm).

Core Components

• Light Source: Deuterium lamp (190–400 nm) or mercury lamp (characteristic spectral lines).

• Monochromator: Uses grating for light dispersion, with an accuracy of ±0.1 nm.

• Sample Cuvette: Quartz cuvette (transmits light in the UV region).

• Detector: Photomultiplier tube (PMT) or CCD array, with sensitivity up to 10?? AU.