Férová - Chitosan concentration NMR relaxometry data

This study presents a novel approach for determining chitosan concentration using T2 relaxation times measured by NMR relaxometry. Chitosan is widely applied in nanomaterials and biotechnology, and accurate quantification of its concentration is essential for various applications. Conventional methods, such as colorimetric and spectrophotometric techniques, often require additional chemicals, complex sample preparation, and are limited to certain concentration ranges. In contrast, our method, is straightforward, rapid, and avoids the need for additional reagents or specific temperature conditions. The concentration of chitosan is determined indirectly by the chitosan-water interface. This biointerface affects the relaxation times of the water molecules that are measured. Samples of chitosan in deionized water were analysed over a concentration range of 5–1000 mg/L using the Bruker minispec mq20 at 40°C and 21°C. T2 relaxation times were obtained using the CPMG sequence, and the data were analysed through monoexponential fitting from Bruker software, CONTIN software, and the Solver algorithm. The results demonstrated that our method produces reliable calibration curves, with the CONTIN software providing a continuous distribution of relaxation times that enables precise quantification. By applying linear regression of Absolute Area (AA) from continuous T2 distribution versus concentration, we achieved highly accurate results, making this method a strong competitor to traditional chitosan quantification techniques.