A discrete analyzer is an instrument designed to automate manual wet chemistry methods by automatically and precisely adding a sample and reagent into a small cell or cuvette, and then allowing a detector to measure the resulting product. Most discrete analyzers are simple to set up and are designed to run samples unattended, enabling high-throughput results and a reduction in laboratory costs. The technology is similar but distinct from continuous flow analyzers, which use segmented flow analysis or flow injected analysis to perform batch analysis on a continuous carrier stream.

Discrete analyzers are generally capable of performing anywhere from 150 to 1,000 tests per hour using minimal reagent volume. The instrument typically consists of a tray that holds numerous sample bottles, a separate tray for storing reagents, a robotic arm with a pipette or syringe, small reaction vessels, at least one detector, and containers used for rinsing and storing waste. The onboard hardware components are usually controlled through software, which the analyst uses to define the desired testing parameters, run calibrations, etc. In fact, most systems have pre-programmed methods.

Once the program is established, the analyst fills the sample bottles and puts them in position in the sample tray. When the program begins, the robotic arm automatically collects the sample with a pipette or syringe and disperses it into a small reaction vessel, along with the appropriate reagent. The reaction vessel mixes the sample and reagent at the desired temperature until it is ready for measurement, at which point the reaction product is read optically using one or more onboard photometric or colorimetric detectors. Afterward, the reaction wells are automatically washed and rinsed, along with the pipette or syringe. The cuvettes storing the samples can be reused or disposed of as necessary. Results of the analysis can be obtained and viewed through the instrument’s software.

Discrete analyzers provide consistently accurate measurements for a variety of applications. The two largest end-markets for the technology are environmental, and agriculture and food labs. Specific applications in environmental testing include analyses of wastewater, drinking water and surface water. For food testing, many discrete analyzer vendors have developed models specifically tailored for one type of product, such as wine, beer, enzymes, proteins, fertilizers or tobacco.

One of the largest suppliers of discrete analyzers is Seal Analytical, which specializes in environmental applications. Their latest model, the AQ400, was released in 2015. Thermo Fisher Scientific offers three models in its Gallery line of discrete photometric analyzers, including the Gallery Plus Beermaster analyzer that is marketed to breweries. Other suppliers include Astoria Pacific, Skalar and Systea.

In 2015, the total market for discrete analyzers was about $30 million. It has grown in recent years as environmental agencies increasingly recommended its methods. Looking ahead, instrument sales are expected to remain modest, sustained by agriculture and food, and other industries looking to replace manual QC testing methods.

Discrete Analyzers at a glance:

Leading Vendors:

• Seal Analytical (Porvair)
• Thermo Fisher Scientific
• Systea

Largest Markets:

• Environmental
• Agriculture and Food
• Government

Instrument Cost:

• $15,000–$200,000