Low-molecular-weight heparin was synthesized by depolymerization of high-molecular-weight heparin with nitrous acid. Preparative chromatography was used to isolate low-molecular-weight heparins with narrow molecular-weight distributions, as confirmed by size-exclusion HPLC. The average molecular weight of the products according to capillary viscometry decreased with synthesis time (4 h) from 14.0 to 3.4 kDa. Fractions with molecular-weight characteristics, ratios of sulfo- to carboxyl groups, and specific activities corresponding to those of low-molecular-weight heparin isolated from commercially available Fragmin^® were isolated among the products. Low-molecular-weight heparins with characteristics analogous to those of Dalteparin and Nadroparin substances could be obtained depending on the treatment time of high-molecular- weight heparin with nitrous acid in acidic medium.

低分子肝素是由高分子肝素与亚硝酸解聚而成。制备色谱用于分离具有窄分子量分布的低分子量肝素，如尺寸排阻 HPLC 所证实。根据毛细管粘度测定法，产物的平均分子量随着合成时间（4 小时）从 14.0 降低到 3.4 kDa。具有分子量特征、磺基与羧基比率以及与从市售 Fragmin ^{® 中}分离的低分子量肝素的比活性相对应的馏分在产品中被隔离。取决于高分子量肝素在酸性介质中用亚硝酸处理的时间，可以获得具有类似于达肝素和那屈肝素物质特性的低分子量肝素。