A rapid separation and quantitation of the stereoisomer amino sugars glucosamine, galactosamine, and mannosamine, along with muramic acid, is needed. These compounds, when their quantities are accurate, can be used to understand the origin and fate of natural organic matter (NOM) in the environment. These target molecules are biomarkers of fungi and bacteria and allow the deconvolution of microbial transformations and degradation of NOM in a wide variety of environmental matrices. Analytical methods applied to this suite of biomarkers are needed to understand carbon and nitrogen biogeochemistry with a changing global climate. Traditional separations of these analytes by gas chromatography require sample derivatization, as does reverse phase liquid chromatography. In contrast, ion chromatography can separate the analytes directly, but requires a separate analytical method to quantify muramic acid. In this work we present a direct analysis of all these molecules using hydrophilic liquid interaction chromatography. Solvent composition, buffer strength, pH, flow rate, and column temperature were optimized. The method can separate these four compounds and the biopolymeric precursor molecule N-acetylglucosamine in a single run in under 8 min with equivalent resolution to the best previously reported separations that did not require derivatization prior to analysis. Detection of the analytes was performed by both tandem and time-of-flight mass spectrometry. The method was assessed for its quantitative capabilities through i) peak area assignment, ii) check standards with ratios of the target analytes likely to be present in real samples, iii) an injection internal standard, and iv) quantitative analysis of real soil hydrolysates by external calibration and standard addition approaches. Across their expected analytical ranges the response for each analyte was highly linear with good accuracy (<25%) and precision (<15%) over three orders of magnitude. Detection limits of 20 µg L-1 were found for galactosamine and 5 µg L-1 for the remainder of the analytes, comparable to the majority of other methods reported in the literature. Overall, this new approach can directly and rapidly quantify amino sugars recovered in environmental hydrolysates.

中文翻译：

---

亲水相互作用液相色谱-质谱法定量分析氨基糖立体异构体和山梨酸生物标志物。

需要对立体异构体氨基糖，氨基葡萄糖，半乳糖胺和甘露糖胺以及山酸进行快速分离和定量。这些化合物的数量准确时，可用于了解环境中天然有机物（NOM）的来源和命运。这些靶分子是真菌和细菌的生物标记，可以使微生物转化解卷积，并在多种环境基质中降解NOM。需要使用适用于这套生物标记物的分析方法，以了解全球气候变化带来的碳和氮生物地球化学。通过气相色谱法对这些分析物进行传统分离需要样品衍生化，反相液相色谱法也是如此。相比之下，离子色谱法可以直接分离分析物，但是需要一种单独的分析方法来量化山mic酸。在这项工作中，我们使用亲水性液体相互作用色谱法对所有这些分子进行了直接分析。优化了溶剂组成，缓冲液强度，pH，流速和柱温。该方法可以在8分钟内一次运行分离出这四种化合物和生物聚合前体分子N-乙酰氨基葡糖，其分离度与以前报道的最佳分离度相同，而无需分析前就可以进行衍生化。分析物的检测是通过串联质谱和飞行时间质谱进行的。通过i）峰面积分配，ii）用标准样品中可能存在的目标分析物的比率检查标准品，iii）注射内标物来评估该方法的定量能力。iv）通过外部校准和标准添加方法对实际土壤水解产物进行定量分析。在其预期的分析范围内，每种分析物的响应高度线性，在三个数量级上具有良好的准确度（<25％）和精确度（<15％）。半乳糖胺的检出限为20 µg L-1，其余分析物的检出限为5 µg L-1，与文献中报道的大多数其他方法相当。总体而言，这种新方法可以直接，快速地定量从环境水解物中回收的氨基糖。15％）在三个数量级上。半乳糖胺的检出限为20 µg L-1，其余分析物的检出限为5 µg L-1，与文献中报道的大多数其他方法相当。总体而言，这种新方法可以直接，快速地定量从环境水解物中回收的氨基糖。15％）在三个数量级上。半乳糖胺的检出限为20 µg L-1，其余分析物的检出限为5 µg L-1，与文献中报道的大多数其他方法相当。总体而言，这种新方法可以直接，快速地定量从环境水解物中回收的氨基糖。