CHRONECT Workstation | MultiMix
Fully automated production of calibration standards and mixes
The preparation of mixes and standards in analytical laboratories is a time-consuming task. It is not only important to ensure correct preparation but also to meet the high requirements for documentation. A lot of data has to be entered and managed manually for individual substances. This is time-consuming and error-prone. The CHRONECT Workstation MultiMix uses software that has been developed for these needs and enables gapless documentation. In combination with the appropriate hardware modules, calibration standards can be created completely automatically. For pesticide analysis, the requirements for the production of calibration standards are regulated in SANTE document 12682/2019. These specifications can also be transferred to other substance groups.
Key Features
- Production independent of working hours through automation
- Less production time than with manual production
- Accuracy of the concentrations can be checked at any time through volumetric dosing and gravimetric precision
- High accuracy
- High reproducibility
- Reliability through integrated controls
- Compliance with guidelines, e.g., SANTE
- Transferable from pesticide analysis to other substance groups
Specifications
| Specs | Values |
| Number of stock solutions in the system | 648 – 1.6 mL vials |
| Drawer system temperature | 4 °C – 40 °C, nitrogen flushed Number of |
| Volumetric flasks for mixes | 8 & 10 mL |
| Number of pipette tips | 576 |
| Supported solvents | 5 |
| Barcode reader | Rotating, supports 1D and 2D barcodes |
| Barcode printer | Included in delivery, including solvent-resistant labels |
| Software equipment | SQL-Server, database application for the administration of analytes, reference materials, stock solutions, mix- tures, CHRONOS automation platform for robot control extended with SQL integration |
| Balance | 220 g maximum load, readability 0.01 mg |
| DeCapper | It supports different vial types |
MultiMix
Modules
Cooled drawer system
An aliquot of the stock solutions is stored in a Peltier-cooled drawer system, which is flushed with nitrogen to exclude moisture. By regularly closing the drawers, the standards are stored in the dark.
2D barcode reader
Traceability is ensured by the use of 2D bar-codes and a software package (Fig. 2). The barcode reader was developed by Axel Semrau and is fully integrated into the system. The software creates suitable labels for the stock solutions, which are printed on solvent-resistant foil by means of a barcode printer. Before each dosage, the barcode is used to check the correctness of the stock solution
Vortex mixer
Re-mixing after heating to room temperature is achieved by using a vortex mixer.
DeCapper
To prevent the septa from being punctured, the vial is opened with a DeCapper before dosing and closed again after collection
Avoidance
of carryover
A further requirement for a system for the preparation of calibration standards that works with highly concentrated standards is the prevention of carryover. In order to exclude any carryover, the CHRONECT Workstation MultiMix uses disposable pipette tips for dosing the stock solutions. These pipette tips are calibrated for the particular solvent used to achieve the target concentration of the analyte as accurately as possible. This calibration is carried out during installation and can be automated at any time by means of a supplied workflow in the control software.
Pipette tips for the liquid handling of stock solutions.
Gravimetric
control
In order to complete the traceability and to ensure the highest possible precision of the created working mixes, each liquid dosage is gravimetrically controlled in the CHRONECT Workstation MultiMix. For this purpose, the system includes a scale with a five-digit display. The weighing results obtained are written directly into the database, thus ensuring complete documentation and the accuracy of the concentration of the analyte in the working mix.
The actual concentrations obtained can be ex-ported to calibration files for GC-MS or LC-MS data systems.
Balance for gravimetric control of the dosed volumes.
Production
time
Depending on the composition, a mix can consist of 500 individual substances, for example, and can take 5 minutes of preparation time to enter the data into the software. The mix is then created fully automatically overnight. The time required is about 20 hours. A corresponding manual process takes about 32 working hours on average. For an 8-hour day, this corresponds to 4 working days.
Commissioning
of the system
All CHRONECT Workstations are pre-installed and tested in Axel Semrau’s application laboratory. Only after passing the Factory Acceptance Test is the system delivered, installed in the customer’s laboratory, and checked again in a Site Acceptance Test. This ensures that the system is immediately ready for routine operation.
MultiMix
software
The core of the supplied software is a substance catalog management, which ensures the integrity of the data through clear, complete documenta-tion. A password-secured SQL database sup-ports the user with the administration and mainte-nance of all important data. Each substance is as-signed a reference.
This consists of information such as:
- CAS name
- Supplier
- Delivery date
- Price
- Solvent
- Opening date
- Date of production
- Expiration date
- Weighing-in
During mix creation, a message also appears if a certain substance has expired and whether this is relevant for further processing or not. The weigh-ing results generated during standard production are transferred online to the database (Fig. 5). This eliminates transmission, spelling and calcu-lation errors.
When creating the mix, a message also appears if a certain substance has run off and whether this is relevant for further processing or not. The weighing results generated during standard pro-duction are transferred online to the database (Fig. 5). This eliminates transmission, spelling and calculation errors.
Existing data from the laboratory’s database can be imported from Excel. For pesticide analysis, a database with more than 600 pesticides is in-cluded in the scope of delivery, so that tedious input routines are no longer necessary. The sys-tem can be expanded to include other analytes at any time. This does not refer exclusively to pesti-cides, but to all fields of application in which mixes have to be generated.
Workflow
and data collection
Workflow and data acquisition by the CHRONECT MultiMix software using the example of the production of a calibration standard for pesticide analysis.
Requirements
of SANTE 12682/2019
The SANTE document sets four criteria:
- Reference substances and stock solutions should be stored in a cool place, preferably in a freezer, excluding light and humidity.
- The documentation created during production should ensure full traceability of all steps.
- The standards should be permanently marked and mixed again after heating to room temper-ature.
- If septa are punctured during standard pro-duction, they should be replaced as soon as possible.
Target
Applications
More than 400 publications, scientific posters and application notes can be found at chronect-symbiosis.com
System Components
SPE Cartridges
DeCapper Module
Pipette-Tool
2D Barcode Reader
