Deuterated chitosan was produced from the filamentous fungus Rhizopus oryzae, cultivated with deuterated glucose in H₂O medium, without the need for conventional chemical deacetylation. After extraction and purification, the chemical composition and structure were determined by Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), and small-angle neutron scattering (SANS). ¹³C NMR experiments provided additional information about the position of the deuterons in the glucoseamine backbone. The NMR spectra indicated that the deuterium incorporation at the non-exchangeable hydrogen positions of the aminoglucopyranosyl ring in the C3 – C5 positions was at least 60–80 %. However, the C2 position was deuterated at a much lower level (6%). Also, SANS showed that the structure of deuterated chitosan was very similar compared to the non-deuterated counterpart. The most abundant radii of the protiated and deuterated chitosan fibers were 54 Å and 60 Å, respectively, but there is a broader distribution of fiber radii in the protiated chitosan sample. The highly deuterated, soluble fungal chitosan described here can be used as a model material for studying chitosan-enzyme complexes for future neutron scattering studies. Because the physical behavior of non-deuterated fungal chitosan mimicked that of shrimp shell chitosan, the methods presented here represent a new approach to producing a high quality deuterated non-animal-derived aminopolysaccharide for studying the structure-function association of biocomposite materials in drug delivery, tissue engineering and other bioactive chitosan-based composites.

氘化的壳聚糖是由丝状真菌米根霉（Rhizopus oryzae）生产的，在H ₂ O培养基中用氘化葡萄糖培养，不需要常规的化学脱乙酰作用。提取和纯化后，通过傅立叶变换红外光谱（FTIR），核磁共振（NMR）和小角中子散射（SANS）确定化学组成和结构。¹³13 C NMR实验提供了有关氘核在葡萄糖胺主链中位置的更多信息。NMR谱表明，氘在C3 – C5位置的氨基葡萄糖吡喃糖基环的不可交换氢位置处的掺入率至少为60–80％。但是，C2位置的氘代水平要低得多（6％）。此外，SANS表明，与未氘代的壳聚糖相比，氘代壳聚糖的结构非常相似。带壳的和脱氘的壳聚糖纤维的最丰富的半径分别为54Å和60Å，但是带壳的壳聚糖样品中纤维的半径分布更宽。本文所述的高度氘化的可溶性真菌壳聚糖可用作模型材料，用于研究壳聚糖-酶复合物，以用于未来的中子散射研究。