In spectral analysis, the material selection of quartz and glass colorimetric dishes directly affects the detection accuracy and applicable scenarios, and their core differences are reflected in three aspects: optical properties, chemical stability, and environmental adaptability.
Comparison of Optical Characteristics
The quartz cuvette is made of fused silica (high-purity silicon dioxide), and its light transmission range covers the ultraviolet to near-infrared light region (185-2500nm), especially in the ultraviolet band (190-400nm), the light transmission rate is more than 80%, and there is no absorption peak, so as to ensure the accuracy of detection data of nucleic acid, protein and other ultraviolet sensitive substances. Its optical uniformity is excellent, grouped, and suitable for high-precision quantitative analysis. The glass colorimetric dish is mainly made of borosilicate glass, with a light transmission range limited to the visible light range (350-2500nm). In the ultraviolet band (<350nm), the light transmission drops sharply to<10%, making it only suitable for conventional visible light detection.
Chemical stability and durability
Quartz colorimetric dishes have strong corrosion resistance and can withstand strong acids, alkalis, and organic solvents such as 6mol/L hydrochloric acid and anhydrous ethanol. They also have high mechanical strength (Mohs hardness level 7) and a surface hardness far exceeding that of glass. They are not easily scratched after long-term use. Its temperature resistance range is from -50 ℃ to+150 ℃, and its thermal expansion coefficient is as low as 5.5 × 10 ⁻⁷/℃, which can withstand rapid temperature changes and impacts. Although glass colorimetric dishes can withstand some acidity, alkalinity, and organic solvents, they are prone to corrosion in hydrofluoric acid (HF) or strongly alkaline solutions, and have poor temperature resistance (generally ≤ 400 ℃), and are prone to deformation at high temperatures.
Selection Guide
Wavelength adaptation: Quartz colorimetric dishes are required for UV detection (such as DNA quantification and drug analysis); Visible light detection (such as biochemistry and environmental monitoring) can use glass colorimetric dishes to reduce costs.
Sample characteristics: Strong corrosive or high-temperature samples require quartz colorimetric dishes; Conventional aqueous solution samples can be measured using glass colorimetric dishes.
Accuracy requirement: For high-precision experiments (such as establishing standard curves), quartz colorimetric dishes are preferred, as their transmittance stability can ensure data reproducibility.
Cost considerations: The unit price of quartz colorimetric dishes is 5-10 times that of glass. If the experimental frequency is low or the budget is limited, glass colorimetric dishes can be used in the short term, but they need to be replaced regularly to avoid a decrease in transmittance.
Typical application scenarios
Quartz colorimetric dish: UV visible spectrophotometer for detecting nucleic acid concentration and protein content; UV absorption analysis of heavy metal ions (such as lead and mercury) in environmental monitoring.
Glass colorimetric dish: Visible light spectrophotometer for measuring food additives and COD in water quality; Conventional colorimetric analysis in teaching experiments.
Quartz colorimetric dishes have become the choice for high-precision detection due to their full band transparency, chemical inertness, and temperature resistance, while glass colorimetric dishes are suitable for routine analysis in the visible light region due to their cost advantage. Experimenters need to make comprehensive decisions based on wavelength requirements, sample properties, and budget to achieve a balance between detection efficiency and economy.