In previous blog posts we have shown how the Spinsolve benchtop NMR spectrometers can be used for accurate quantitative NMR analysis based on internal or external standards. While in those posts we mainly focused on demonstrating the high accuracy and reproducibility delivered by the Spinsolve, here, we want to present the qNMR module that is available in the Spinsolve software to automate the measurement, data processing, and report generation. This user interface is especially useful when these measurements are required for quality control at the production site, where typically non-NMR experts need single click solutions.
The Spinsolve qNMR software module has been designed to allow for a quick and easy set-up of qNMR methods, while offering flexible processing functions to accommodate the different types of applications. Methods using internal or external standards can be generated through a graphical user interface where a variety of graphical data visualization and statistical tools are available. Moreover, the qNMR plug-in is fully integrated with the Spinsolve audit module to provide user management as well as full traceability of all measurement and processing steps. This feature is particularly required in GxP regulated environments.
To demonstrate how easy it is to work with the qNMR module, we took as an example the implementation of the assay determination of diclofop methyl, which was discussed in an earlier blog post. As described there, the assay of a substance can be determined by using the following equation :
While the molecular weights and the number of hydrogen nuclei are predefined, methods will only require the user input of the weights as well as the assay of the reference standard for each measurement. As shown in Figure 1 the qNMR module allows to define the user interface in a way, where only the input parameters that vary from batch to batch can be adjusted, resulting in an easy-to-use interface. Once the measurement has been started via the “ACQUIRE NOW” button all the following steps from data acquisition, processing, analysis, and report generation are fully automated.
Figure 1: The user input parameter, data display and results panels of the qNMR module which also allows for a complete automatic report generation
Administrators who have configuration access can set up new methods or modify existing methods and do have access to all acquisition, processing, and analysis parameters via the graphical user interface. In addition to the standard one-pulse proton experiment, qNMR methods can be set up with more advanced pulse programs including heteronuclear decoupling or solvent suppression. Moreover, different nuclei like 19F, 31P, 7Li, or 23Na can be also used for the quantification.
Figure 2: List of protocols available for automated qNMR measurements.
The qNMR module can be set up for quantification based on external standard calibrants, which have proved very valuable for the analysis of liquid samples coming directly from the process, without the need of any sample preparation. We have discussed such an example in a previous blog post. A method can use several external standards as a reference either to allow the quantification of different analytes in a mixture or for multipoint calibrations.
Figure 3: An external qNMR method with three calibration measurements loaded which are set to be the default calibration for this method.
To allow simple integration in GLP/GMP regulated environments, the qNMR module is fully embedded in the user management and audit module of the Spinsolve software. In this way, all steps are fully traceable with the audit trail functionalities.
Figure 4: The audit trail of a qNMR measurement after adding a lot number and the solvent to the measurement parameter.
To enable fully unattended automated analysis the qNMR methods can be run in the queue of the Spinsolve autosampler. In this way, throughput can be maximized and measurements can be done in a fully systematic way, where all time intervals like sample insertion, sample warm up, and protocol delays are controlled.
The described features make the Spinsolve an outstanding solution for quantification tasks where high performance, full automation, and ease of use are required. If you want to learn more about the possibility of automated quantification with the Spinsolve contact us through .