Compact Sample Preparation Unit

Nucomat, a laboratory automation specialist for several decades, presents a modular unit for multiple acid dispensing and sample digestion. The compact sample preparation unit is a mobile laboratory instrument that includes pneumatically operated refill pumps for endless operation from a remote bulk container.


  • Accurate and fast liquid dispensing
  • Gravimetric control
  • Modularity
    • 1 to 4 Reagents
    • Optional integrated infrared digestion
  • Compatible with multiple recipients and racks
  • Leach caps for reflux operation
  • Highly resistant to concentrated acids
  • User configurable
  • LIMS interfacing
  • Safe operation
  • Automatic refilling from bulk containers


  • In batch mode a rack of up to 40 tubes can be filled with concentrated acids with an accuracy of ±20 mg in only a couple of seconds.
  • An integrated balance with a resolution of 10 mg assures that the right amount of acid is dispensed in every step of the method.
  • For improved sample integrity the unit can be configured for tube per tube operation at a lower throughput.


The base unit is a single acid dispenser with integrated balance. It can be equipped with an infrared hotplate for sample digestion and up to three additional liquids.

In case the unit needs to be expanded, the installation of an additional liquid is plug & play and can be done on-site by the customer.


Infrared was chosen because of some properties that traditional hotplates simply cannot offer:

  • High power for fast heating up to 300 °C
  • Instantly on, meaning no start-up delay
  • Instantly off, enabling accurate digestion time
  • Power control for syrupy state digestion
  • Ability to use different power levels in different method steps


The unit can be configured for use with 4 standard types of recipients.

  • 20 ml glass tubes in a 4×10 rack
  • 50 ml glass or PTFE beakers in 2 [5 x 4] racks for a total size of [5 x 8]
  • 100 ml glass or PTFE beakers in 2 [5 x 3] racks for a total size of [5 x 6]
  • 250 ml glass or PTFE beakers in 2 [4 x 2] racks for a total size of [4 x 4]

Upon customer request the unit can be customised for usage of a different type of recipient.

For all standard beakers Nucomat provides the possibility to use our patented leach caps to reduce evaporation during digestion and reflux operation. With these leach caps the evaporation can be reduced to a similar level as with watch glasses but they are designed to enable the device to dispense through the cap to avoid the need to remove them manually in the middle of the process. Additionally, the cap is made in such way that the surface of the beaker is washed down with the dispensed liquid.


The device is designed to be used with concentrated acids, more specifically a lot of attention was paid to corrosion resistance of all used materials:

  • Fume hood constructed in PVC
  • Refill pump and dispensing valves:
    • Air operated
    • PFA body parts
    • All wetted parts made from PTFE

Download the product brochure here: Compact sample preparation unit brochure


A user interface is provided with the unit to enable the operator to view the status of the device and to configure the operation to their needs.