Safety

Manual processes can expose the operator to hazardous or toxic solvents and compounds. The XPR Automatic Balance offers automated liquid dispensing, which minimizes the likelihood of spillages and exposure risks during sample and standard preparation. This improves safety and reduces balance cleaning requirements, potentially saves time.

Productivity

Automated solvent dispensing improves throughput by avoiding repetitive, time-consuming manual weighing and dilution steps. Standard solutions can be prepared faster without multiple dilution series, using the XPR Automatic Balance, it is possible to achieve a dilution factor of 10,000 in a single step.

Accuracy

Accuracy is key in any analysis. Automated solvent dispensing helps ensure preparation of consistently accurate solutions by automatically calculating the amount of solvent needed to achieve the target concentration. It reduces interference from environmental influences as well as inter-operator variability, and helps avoid human errors during the preparation of solutions, calculation of concentrations, and recording of data.

Compliance and Process Security

Manual errors in data recording and transfer – balance terminal to lab notebook to spreadsheet and then LIMS – are eliminated. When using a XPR Automatic Balance, data is fully traceable and easily retrieved for audit purposes.

It is universally accepted that a gravimetric measurement is intrinsically more accurate than a volumetric measurement. In fact, pipettes and volumetric measuring equipment are calibrated using gravimetric methods. In a fully gravimetric system, the user defines the concentration required and the target amount of solution. The system software calculates the target amount of a solid to dispense and then delivers the appropriate amount of diluent to prepare an extremely accurate and precise concentration according to the actual amount of solid dispensed. In a liquid dispensing system, the software calculates the required amount of diluent according to the actual amount of solid dosed manually; the result is still a highly accurate concentration. Implementing a gravimetric sample preparation system reduces laboratory errors and Out-of-Specification (OOS) incidents by up to 50 percent, while simultaneously increasing laboratory efficiency and reducing waste.

Would you like to prepare standard solutions faster and avoid repetitive, time-consuming manual weighing and dilution steps? Do you want to prepare highly precise concentrations down to 0.1 mg/g in just one step? Do you want to reduce potential errors in the calculation of concentrations and recording of data?

For further information or support regarding automated solvent dispensing, our team of experts is here to help. Please do not hesitate to contact us.

The XPR Automatic Balance is the ideal partner for accurate solution preparation. Combined with the liquid dispensing module, it makes gravimetric sample preparation highly accurate and simple to achieve.

1. Simply weigh your sample or standard, as you would normally, into the appropriate vessel on the XPR Automatic Balance. 
2. Select the concentration you require
3. Automatically dispense the required solvent: the amount of solvent to be added will be calculated automatically based on the amount of solid weighed out in step 1 and dispensed gravimetrically.

The key advantages to the automatic approach are:

• Only produce the quantity you require – no need to fill a volumetric flask – saving on solvent and disposal costs.
• As the minimum weight associated with the XPR Automatic Balance is lower compared to any other manual dosing balance, you can weigh smaller quantities of samples or standards. This preserves precious or valuable substances that may only be available in limited quantities, ultimately reducing costs.
• The concentration achieved is of the highest accuracy because of the precise and non-subjective gravimetric measurement, providing confidence that the end results are also of the highest quality.
• The solid does not have to be weighed out as diligently, because the amount of solvent added is automatically calculated based on whatever quantity is actually weighed out. For samples that are tricky to weigh quickly and precisely, such as viscous samples like honey, this make the task significantly easier and saves a lot of time.
• Errors in calculations and data recording are avoided, because all results – sample and solvent weight, and the concentration achieved – are automatically recorded electronically. This ensures no mistakes are made when writing down results manually, during the transcription of results into Excel, or in the calculation of the concentration required.
• No volumetric flasks or pipettes are required, avoiding any volumetric errors and cross-contamination, and reducing the cleaning / washing challenges on the laboratory.
• Serial dilutions can be reached efficiently, without multiple dilution series, the XPR Automatic Balance can achieve a dilution factor of 10,000 in a single step.

• Preparation of samples and standards for trace metal analysis by ICP-MS (inductively coupled plasma-mass spectrometry), where accurate concentrations are critical when concentrations are as low as 0.001 µg/g.
  

Download the Application Note "Cost-Efficient Trace Metal Analysis With Gravimetric Solution Preparation"

• Preparation of pesticide standard solutions for pesticide residue testing by LC-MS (liquid chromatography-mass spectrometry) or GC-MS (gas chromatography-mass spectrometry), where each sample needs to be analyzed for several hundred different pesticides at a time.
  

Download the Application Note "Efficient Pesticide Residue Testing – Automated Standard Preparation"

• Preparation of honey samples for food authenticity testing, where weighing of a specific amount of a very viscous substance to prepare an accurate concentration is a challenging task.
  

Download the Application Note "Fast and Accurate Sample Preparation: Authenticity Control of Honey and Olive Oil"

A METTLER TOLEDO XPR Automatic Balance equipped with a liquid dosing module enables you to prepare highly accurate standard solutions and dilution series. For a full workflow solution, it can be combined with LabX™ laboratory software, offering the benefits of comprehensive data handling and sample tracking functionalities.

LabX provides step-by-step SOP instructions on the balance display. All data is handled automatically by LabX and saved in a secure, centralized database to ensure full traceability. Manual documentation is no longer necessary, eliminating transcription errors entirely.

Labels can be customized to include user ID, sample ID, actual concentration, production date and expiry date. Connecting a barcode reader allows sample and reference standard IDs to be read electronically. With the addition of a printer, labels can be printed automatically.