Why are quartz cuvettes used in UV spectroscopy?
Quartz has the capability of more light transmission and is more transparent. So, it is used for sensitive experiments. Besides, quartz is more temperature resistant. At the same time, glass and plastic cuvettes are not ideal for concentration and purity measurements.
IR Quartz is great choice for cuvettes for UV VIS measurements. The transmission range is 220-3,500 nm so you get some of the UV, but you get a nice range in the IR as well. Sapphire is an amazing cuvette material. Sapphire is a super hard material making it damage resistant and very hard to scratch.
Quartz Cuvette:
Quartz is expensive in comparison with glass and transparent plastics but has the additional benefit of covering both UV and visible regions right from 190 nm. However, it is even more fragile than glass and the cuvettes need to be handled with greater care.
Chemical Compatibility – The chemical structure of quartz is stronger than glass making it able to handle a bigger range of chemicals that would melt or damage a glass cuvette.
Glass and Quartz Cuvettes
Glass cuvettes are used for measurements in the visible range from 320 to 2500 nm. Quartz cuvettes deliver precise results in the whole UV and visible range from 200 to 2500 nm. The smaller the manufacturing tolerance, the better and more repeatable the measurement.
If wavelengths in the UV-range, below approximately 300 nm, are employed, cuvettes made from quartz glass, or a special type of plastic, which provide sufficient transparency in this range, must be used (figure 2).
you cannot use plastic cuvettes in UV region. You will experience too much fluctuation of absorbance. Rather used quartz cuvettes, because are stable in that range.
Ultraviolet light has shorter wavelength than visible light, although ultraviolet waves are invisible to human eyes. If we use glass in place of quartz then glass will absorb ultraviolet rays while quartz does not. Ultraviolet radiant has a low power of penetration, hence it directly affects the human body as well.
Quartz is a good transmitter of UV rays. The UV range is from 0.1 nm to about 400 nm (or from 100 A to about 4000 A). The visible light wavelengths are longer, between 400 nm and 700 nm. Quartz will transmit UV from 180 nm to 400 nm.
Fused Quartz is normally transparent. features high transparency within ultraviolet and visible regions. It has no absorption bands within 170-250nm wavelength interval. It has an intensive OH-absorption band at 2600-2800nm wavelength range.
Why glass is not used in UV spectroscopy?
Why is a glass cuvette not suitable for UV? Because glass and most plastics absorb ultraviolet light, reusable quartz cuvettes were formerly required for measurements in the ultraviolet range.
Cuvettes are made from glass, plastic, or optical-grade quartz. Plastic cuvettes have the advantage of being less expensive and disposable and are often used in fast spectroscopic assays. Quartz and glass cuvettes are used when organic solvents are involved, which have higher resistance compared to plastic types.
Generally used in spectroscopy, cuvettes are designed to hold liquid substances during chemical analysis. These instruments have two or four optical clear windows to ensure you can use light waves to measure the substance of interest without interference from the cuvette itself.