QUANTOS Compared

 

QUANTOS in direct comparison to HPLC (High Performance Liquid Chromatography):

Measurement speed, ease of analysis, personnel costs and training, robustness and maintenance

– QUANTOS outperforms HPLC in all essential aspects.

Range and Duration

How many ingredients can be measured using a single device?

Q: All measurements can be performed with the same QUANTOS.

HPLC: Different ingredients require different HPLC columns and, in many cases, special detectors. More complex devices for collecting several measurements are expensive or provide inaccurate data (diode array detectors). Each method must be calibrated separately, and different methods and working media must be used depending on the combination of ingredients.

How many ingredients can be analysed in a single measurement?

Q: One measurement captures all of the ingredients and parameters of a sample using infrared spectroscopy. It is also possible to conduct certain analysis applications at a later date, or even individual searches for particular signals.

HPLC: One measurement often only captures certain classes of substance, as individual HPLC methods are usually only suitable for a small range of substances.

How long does it take to capture all measurable parameters of a sample?

Q: All of the measurable parameters of a sample are captured in a single measurement within a few minutes. All molecular components are captured and are permanently available. This is why we call it a digitised sample: once the measurement has been taken it can be analysed globally within seconds just as well as in the Analyzer itself.

HPLC: Different analyses have to be performed for different classes of substance and parameters. Depending on the laboratory equipment and staff, the analysis time for all measurable parameters exceeds one working day. Analyses in an HPLC are often time-consuming. An individual analysis can take 45 minutes or longer. In addition to this, subsequent cleaning, equilibration and recalibration steps are needed to ensure that the HPLC unit functions properly and accurately in the long term.

How complicated is it to prepare the device before each measurement?

Q: The cell is automatically rinsed as part of every measurement. QUANTOS is self-cleaning. Optimum measurement conditions are automatically maintained in QUANTOS.

HPLC: The measuring cell must be thoroughly cleaned by hand. In addition to a clean column and stable temperature, regular calibrations are essential for reliable measurement results. New columns can modify the results. The integration limits must be chosen carefully.

Cost and Effort

What education and training is required for measuring and preparing samples (pre-analysis)?

Q: Basic handling of an injection and filter is the most complex aspect of sample preparation. Any employee can operate the QFOOD Analyzer after a quick briefing.

HPLC: Operation and calibration should only be performed by trained specialists, sample preparation and operation of the high-pressure liquid chromatography systems require technical laboratory training.

What are the consumption and ancillary costs?

Q: QUANTOS is robust and is cheap to maintain. A cell does not have to be replaced until approximately 10,000 measurements have been performed. The samples are filtered and injected into the measuring vessels without using any additional sample vessels. A quick briefing, even for staff with no knowledge of laboratory analysis, is enough to be able to properly operate the QUANTOS Analyzer. Personnel costs are therefore very low. There are no expensive care and calibration steps either, the fully automated procedures are sufficient for this.

HPLC: Ongoing costs for service and consumables are high: Chromatography columns are sensitive to operating errors and must be regularly cleaned or replaced. Good specialist knowledge and experience are essential to produce reliable measurement results. Extra vessels are needed to prepare the samples. This results in higher costs for staff and materials.

How complex is the analysis (calibration, monitoring, sample preparation)?

Q: QUANTOS calibrates itself according to automated routines. Calibration curves are performed after any hardware is replaced and provide the new references. They ensure consistently precise measurements.

HPLC: Reference and calibration standards must be established, regularly measured and stored according to specifications. The water content of the standards, and imprecise weighing and filling are sources of error. Overall, the calibration is time-consuming and expensive and must be performed by specialist staff, ideally always the same person.

What education and training is required to analyse and evaluate the results?

Q: Any employee can operate the QFOOD Analyzer after a quick briefing. The results of the QFOOD Analyzer can be interpreted by any layperson after a brief training period. Discrepancies in results are shown in a manner that is similarly easy to understand.

HPLC: Common HPLC systems can only be operated by trained analysis staff. Columns must be carefully “primed”, otherwise they can be easily damaged or cannot perform to their full extent. The expected results can be easily interpreted. However, if ingredients appear that are unexpected e.g. in the method, only specialists are capable of noticing the error upon careful inspection.

Robustness and Quality of Results

How susceptible is the measurement result to user error?

Q: Usually, the sample is simply filtered and then poured into a measuring vessel. Internal standards or changes to the sample composition are not necessary, which thus prevents user influence and the associated error rate on the part of the device.

HPLC: Before the measurement, various steps are often necessary to prepare the sample (e.g. changing the concentration, separating solid or dissolved interfering substances, chemically modifying the substances to be analysed etc.), which can all lead to inaccuracies and distortions. Internal or external calibrations also have to be performed, which are often time-consuming and labour-intensive and are also an additional source of error.

How reliable are the measurement results if disruptions occur, e.g. process or system errors?

Q: Errors mostly occur in the form of a deviation from the target value and are usually easy to identify throughout the entire spectrum. Process errors can generally be easily verified through the numerous ingredients, and even bacterial contamination can be seen depending on the state.

HPLC: Process or system errors often occur in an unpredictable manner, so it is rare to be able to draw conclusions about the error from the measurement results. This is the downside of the limited view of individual parameters.

Food samples are complex with many parameters and qualitative information e.g. on freshness and contamination. Is all information from the sample analysed?

Q: Since most samples are injected into QUANTOS unchanged, each measurement generates an overall picture of the sample with no distortions and with all measurable ingredients, including parameters such as pH value. The analysis of the entire sample matrix can also provide numerous qualitative statements about e.g. freshness, bacterial contamination and the organic quality of the sample. The measurement can be described as a digitised sample and contains the information of all molecular components and their secondary information. Only ingredients that are removed during filtration cannot be captured. Unexpected ingredients are always captured too and can be analysed. Analyses on new substances can also be performed subsequently with the available spectrum at any time.

HPLC: Individual classes of ingredients in a sample must be measured separately from each other. Qualitative statements are often based on interactions between ingredients. If they are only measured separately from each other, it is almost impossible to make useful qualitative statements. Parameters such as viscosity etc. must be captured as well using other methods. During a routine analysis, unknown ingredients are a problem because, at best, they are detected as an error. Normally, they are not identified but can have a negative impact on the relevant peaks or affect – or even damage – the column material, rendering it useless for subsequent measurements, without this being noticed.

What happens when unexpected or unknown substances are in the food sample?

Q: This does not affect the measurement results as long as the molecules do not directly react with each other. If unknown peaks occur in the result spectra, this does not affect the actual analysis. It is possible that the new ingredients cannot be identified and quantified, which results in a warning message. If necessary, further analysis steps can be initiated.

HPLC: Peaks resulting from unknown substances can overlap with regular peaks and in principle lead to incorrect results. The column can become contaminated and distort the measurement results. Incorrect measurement results can only be detected by very expensive devices and validated at a later date.

(Unknown or unexpected ingredients must not render measurement results unusable. An example of this is the disaster with melamine in milk. A good test should have shown immediately that a poisonous synthetic material had been added and not protein).

Can unknown ingredients lead to incorrect or inaccurate results?

Q: All IR-active ingredients within the measuring tolerance are captured. Each substance generates its own peak on the wave spectrum. QUANTOS works very reliably and generates completely reproducible results at a scientific level. Unexpected ingredients are always captured too and can be analysed. Analyses on new substances can also be performed subsequently with the available spectrum at any time.

HPLC: The HPLC routine analysis generally only detects substances that are searched for. At best, unknown compounds are detected as separate peaks, in the worst case, they are “hidden” in the peaks of the ingredients that are searched for and therefore remain undetected. It is also possible that the connected detection method is not able to detect the unknown substances. This can seriously distort measurement results or these undetected ingredients result in blockages or damage to the HPLC column.

Is the food sample after preparation still comparable with the original, are the conclusions therefore representative of the product?

Q: The ingredients are measured in a native state (i.e. in an aqueous medium) and are not altered as a result of the measurement. This means that we get completely accurate information. All parameters are captured both quantitatively and qualitatively.

HPLC: In order to measure them, molecules are physically or chemically separated according to a single criterion (e.g. according to molecular weight or polarity). The different fractions are then measured in order in the column over different periods of time. This means similar molecules can sometimes not be sufficiently distinguished from each other. For some separation and detection methods, it is necessary to modify the molecules beforehand. Therefore, some substances can show a different structure following chromatographic separation.