Spectrophotometer: Principle, Applications, and Scientific Importance
The spectrophotometer is a core analytical instrument used in biotechnology, chemistry, molecular biology, clinical diagnostics, and environmental science.
What Is a Spectrophotometer?
A spectrophotometer is an analytical device that measures how much light a substance absorbs or transmits at specific wavelengths. This information allows scientists to quantify concentrations, assess purity, and monitor biochemical reactions.
Principle of Spectrophotometry
Spectrophotometry is based on the Beer–Lambert Law, which establishes a linear relationship between absorbance and concentration.
A: absorbance · ε: molar absorptivity · l: path length · c: concentration
Main Components
- Light source: Deuterium (UV) or tungsten-halogen (visible)
- Monochromator: Selects precise wavelengths
- Sample holder: Quartz, glass, or plastic cuvettes
- Detector: Converts light into measurable signals
Types of Spectrophotometers
| Type | Wavelength Range | Main Applications |
|---|---|---|
| UV-Visible | 190–1100 nm | DNA, RNA, protein analysis |
| Microvolume | UV-Vis | Low-volume nucleic acid quantification |
| Double-Beam | UV-Vis | High precision and stability |
| FTIR | Infrared | Chemical structure analysis |
Scientific Applications
- Molecular biology: DNA/RNA concentration and purity
- Biochemistry: Enzyme kinetics and protein assays
- Clinical diagnostics: Blood and metabolite analysis
- Environmental science: Water and pollutant monitoring
- Pharmaceutical QC: Drug stability and formulation testing
Spectrophotometry remains a fundamental analytical technique, offering speed, accuracy, and versatility across scientific disciplines.
Spectrophotometer: Principle, Applications, and Scientific Importance
The spectrophotometer is a core analytical instrument used in biotechnology, chemistry, molecular biology, clinical diagnostics, and environmental science.
What Is a Spectrophotometer?
A spectrophotometer is an analytical device that measures how much light a substance absorbs or transmits at specific wavelengths. This information allows scientists to quantify concentrations, assess purity, and monitor biochemical reactions.
Principle of Spectrophotometry
Spectrophotometry is based on the Beer–Lambert Law, which establishes a linear relationship between absorbance and concentration.
A: absorbance · ε: molar absorptivity · l: path length · c: concentration
Main Components
- Light source: Deuterium (UV) or tungsten-halogen (visible)
- Monochromator: Selects precise wavelengths
- Sample holder: Quartz, glass, or plastic cuvettes
- Detector: Converts light into measurable signals
Types of Spectrophotometers
| Type | Wavelength Range | Main Applications |
|---|---|---|
| UV-Visible | 190–1100 nm | DNA, RNA, protein analysis |
| Microvolume | UV-Vis | Low-volume nucleic acid quantification |
| Double-Beam | UV-Vis | High precision and stability |
| FTIR | Infrared | Chemical structure analysis |
Scientific Applications
- Molecular biology: DNA/RNA concentration and purity
- Biochemistry: Enzyme kinetics and protein assays
- Clinical diagnostics: Blood and metabolite analysis
- Environmental science: Water and pollutant monitoring
- Pharmaceutical QC: Drug stability and formulation testing
Spectrophotometry remains a fundamental analytical technique, offering speed, accuracy, and versatility across scientific disciplines.