Research and Development

@article{Dimzon2014,

title = {Degree of deacetylation of chitosan by infrared spectroscopy and partial least squares},

author = {Ian Ken D. Dimzon and Thomas P. Knepper},

url = {https://www.sciencedirect.com/science/article/abs/pii/S0141813014006631},

doi = {10.1016/j.ijbiomac.2014.09.050},

year  = {2014},

date = {2014-10-12},

journal = {International Journal of Biological Macromolecules},

volume = {72},

pages = {939-945},

abstract = {The determination of the degree of deacetylation of highly deacetylated chitosan by infrared (IR) spectroscopy was significantly improved with the use of partial least squares (PLS). The IR spectral region from 1500 to 1800 cm−1 was taken as the dataset. Different PLS models resulting from various data pre-treatments were evaluated and compared. The PLS model that gave excellent internal and external validation performance came from the data that were corrected for the baseline and that was normalized relative to the maximum corrected absorbance. Analysis of the PLS loadings plot showed that the important variables in the spectral region came from the absorption maxima related to the amide bands at 1660 and 1550 cm−1 and amine band at 1600 cm−1. IR-PLS results were comparable to the results obtained by potentiometric titration. IR-PLS results were found to be more precise and rugged compared to the usual IR absorbance ratio method. This is consistent with the fact that IR spectral resolution is not really high and that the absorption at a single wavelength is influenced by other factors like hydrogen bonding and the presence of water.},

keywords = {chitosan, degree of deacetylation, partial least square},

pubstate = {published},

tppubtype = {article}

}

@article{Dimzon2012,

title = {The interaction of chitosan and olive oil: Effects of degree of deacetylation and degree of polymerization},

author = {Ian Ken D. Dimzon and Jürgen Ebertb and Thomas P. Knepper},

url = {https://www.sciencedirect.com/science/article/abs/pii/S0144861712009526},

doi = {10.1016/j.carbpol.2012.09.035},

year  = {2012},

date = {2012-09-28},

journal = {Carbohydrate Polymers},

volume = {92},

number = {1},

pages = {564-570},

abstract = {The combined effects of degree of deacetylation (DD) and degree of polymerization (DP) on the ability of chitosan to interact with olive oil was studied. The oil-binding test, a method that makes use of olive oil as a representative fat, was adopted as a measure of the interaction of chitosan and olive oil. The oil-binding capacities of twelve chitosan samples with DPs ranging from 470 to 1450 and DDs of 75% to 95% were determined. The oil-binding capacities were then correlated to the DD and DP using partial least squares (PLS) regression. The generated PLS model had a root mean square error of prediction (RMSEP) of 9.1%. Results indicated that oil-binding capacity is a function of DD more than of DP. For chitosan with DD at the interval 50% < DD < 90%, a negatively sloped linear correlation was obtained for DD and oil-binding capacity suggesting that hydrophobic intermolecular forces of attraction dominates the interaction of chitosan with olive oil. For chitosan with DD > 90%, the observed deviation from the linear correlation increased. In this interval, free fatty acid anions facilitate the interaction of chitosan and olive oil. Free fatty acids form a stable ionic interaction with the former and a strong hydrophobic interaction with the latter.},

keywords = {chemometrics, chitosan, degree of deacetylation, degree of polymerization, oil-binding capacity, pls},

pubstate = {published},

tppubtype = {article}

}