Spectrophotometers and consumables

In most cases, a simple spectrophotometer at an affordable price is sufficient for routine measurements. The photometer is accurate and reliable. Expensive spectrophotometers are needed for specific analysis.

The choice of any type of spectrophotometer is determined by the requirements of regulatory documents (methods or standards), according to which you will analyze substances. The regulatory documents using the photometric method of analysis regulate the wavelength λ, the length of the optical path of light in the cuvette, the requirements for the spectral width of the slit and the need for scanning can be specified.

The main parameters taken into account when choosing spectral devices:

1. The wavelength λ at which the optical density is measured.
   If the wavelength in the visible range is 315–1000 nm, then a photometer with a spectral range of 315 (325)–1000 nm is selected. If at least one of the methods requires the use of wavelengths shorter than 315 nm, then a photometer operating in the UV and visible range is selected: 190–1000 nm. Such spectrophotometers are usually much more expensive than those operating only in the visible range (315–1000 nm). If you buy a spectrophotometer operating in the UV range “for the future”, you need to take into account that the deuterium lamp, used only in the UV range, has a limited service life, and its replacement is quite expensive.
2. The length of the optical path of light in the cuvette.
   The length of the optical path determines the parameters of the cell holder of the photocolorimeter. Not all instruments are designed for 100 mm cuvettes. Cuvettes with an optical path length of 100 mm are required in a small number of methods and standards and are also sometimes used when working with low concentrations of a substance.
3. Width of the spectral slit of the device.
   The narrower the slit, the better the device can resolve two absorption bands closely spaced from each other. Devices with a slit width of 4 nm and 0.4 nm may differ in cost by up to 20 times. If the resolution of bands with a half-width of 1 nm is not required (and the volume of such tasks is less than 0.01% of the total number of all measurements in different industries), it is sufficient to buy a spectrophotometer with a slit width of 4 nm.
4. Scanning.
   The built-in fast spectrum scanning function is necessary for frequent scanning of the entire spectrum or its individual ranges. If scanning is required rarely, it is more economical to choose photocolorimeters that scan the spectrum using computer applications.

Additional criteria for choosing a spectrophotometer

• Two-beam devices.
  They are used for accurate high-speed scanning or when it is necessary to instantly obtain the difference in optical densities in two cuvettes. Two-beam devices usually already have a spectral slit of less than 4 nm and a built-in scanning function.
• Type of cuvette holder.
  The width of an ECROS-type cuvette (24 mm) or a EURO cuvette (12.5 mm) does not affect the analysis result and is determined by user preference. You can choose a spectrophotometer with the cuvette holder that is more convenient for you.
• Quality of cuvettes and device adjustment.
  If the cuvettes have a wedge shape, then when installed in the holder with a 180-degree rotation around the vertical axis, the transmission value may change by several percent. The photocolorimeter must be adjusted so that the difference in readings is minimal.
• A set of control light filters.
  Allows you to check the device before annual verification, promptly monitor the correctness of measurements, practice operating skills and conduct laboratory work.
• Warranty.
  Before buying a photocolorimeter (photometer), pay attention to the warranty period and the reliability of the manufacturer, the possibility of quickly obtaining technical and informational support, as well as the option of developing software for specific tasks.
• USB port.
  Most modern photometers can be connected to a computer via a USB port. A USB port is required if the device is supplied with software that allows you to process results and print a finished report.
• Touch screen.
  Some spectrophotometers are equipped with a touch screen. It makes sense to overpay for this function only if it is convenient to operate the device with rubber gloves using a small touch screen.

Attention! Very often, for advertising purposes, manufacturers indicate inflated characteristics of their devices. The actual characteristics are specified in the description of the type of measuring instruments entered into the State Register under a specific number. Information about the description and validity period of the certificate can be found on the website: http://www.fundmetrology.ru

Spectrophotometers manufactured by ECROSKHIM LTD, St. Petersburg, are a time-tested, reliable classic of spectral equipment for everyday measurements.

• Entered in the State Register of Measuring Instruments No. 44866-10.
• Manufactured and verified in St. Petersburg (according to TU 9443-001-5627822-2009, about 6,000 PE series spectrophotometers were produced).
• Reliable devices (warranty period – 3 years).
• Easy to operate (very detailed user manual).
• User training in operation and configuration with the issuance of a certificate is available.
• High photometric measurement accuracy.
• Free set of light filters.
• Large cuvette compartment allows installation of holders for 24 mm ECROS cuvettes or 12.5 mm cuvettes.
• Device readings do not depend on sample displacement along the optical axis.
• The design of the cuvette holder allows staggered installation of cuvettes, increasing the distance between them and simplifying installation.
• Ability to use cuvettes up to 100 mm long.
• Device adjustment partially compensates for possible cuvette wedge shape.
• Connection to a computer via USB port.
• Free software significantly reduces laboratory work time.
• Optional delivery with a computer and installed software.
• Additional software allows spectrum scanning (for PE5400VI/5400UF devices).
• Registration certificate No. ФСР 2010/07089 dated March 10, 2010, confirming that the devices manufactured by Ekroskhim LTD, Russia, are medical devices.
• Photometers are exported to Belarus, Kazakhstan, Kyrgyzstan, Nigeria and other countries, including China.