ImatraNMR: novel software for batch integration and analysis of quantitative NMR spectra.

Quantitative NMR spectroscopy is a useful and important tool for analysis of various mixtures. Recently, in addition of traditional quantitative 1D (1)H and (13)C NMR methods, a variety of pulse sequences aimed for quantitative or semiquantitative analysis have been developed. To obtain actual usable results from quantitative spectra, they must be processed and analyzed with suitable software. Currently, there are many processing packages available from spectrometer manufacturers and third party developers, and most of them are capable of analyzing and integration of quantitative spectra. However, they are mainly aimed for processing single or few spectra, and are slow and difficult to use when large numbers of spectra and signals are being analyzed, even when using pre-saved integration areas or custom scripting features. In this article, we present a novel software, ImatraNMR, designed for batch analysis of quantitative spectra. In addition to capability of analyzing large number of spectra, it provides results in text and CSV formats, allowing further data-analysis using spreadsheet programs or general analysis programs, such as Matlab. The software is written with Java, and thus it should run in any platform capable of providing Java Runtime Environment version 1.6 or newer, however, currently it has only been tested with Windows and Linux (Ubuntu 10.04). The software is free for non-commercial use, and is provided with source code upon request.

Quantitative (13)C NMR spectroscopy using refocused constant-time INEPT, Q-INEPT-CT.

Quantitative NMR spectroscopy is a useful tool for the analysis of various mixtures. Usually (1)H NMR is used for quantitative measurements, but in many cases the better signal dispersion offered by (13)C NMR is beneficial. However, the low natural abundance of (13)C and long T(1) relaxation times make the acquisition of quantitative (13)C spectra with adequate signal-to-noise ratio time-consuming. The use of polarization transfer experiments such as DEPT or INEPT can offer improved signal intensity and faster repetition rate, but yield non-quantitative results. In this paper we present a pulse sequence based on constant-time INEPT, Q-INEPT-CT, which is capable of producing quantitative carbon spectra with better sensitivity and/or in less time than traditional quantitative (13)C. Additionally, the constant length of the sequence means that signal loss due to relaxation effects can be relatively easily corrected. Thus, the presented sequence is a valuable tool when quantitative carbon data is required quickly and/or low-concentration samples are involved.