Water enriched with oxygen‐18 (H₂¹⁸O) is a potential tracer for evaluating the sources of glucose and glycogen synthesis since it is incorporated into specific sites of glucose‐6‐phosphate via specific enzyme‐mediated exchange/addition mechanisms. Unlike ²H, ¹⁸O does not experience significant isotope effects for any of these processes. Therefore, H₂¹⁸O might provide more precise estimates of endogenous carbohydrate synthesis compared with deuterated water provided that positional ¹⁸O enrichments of glucose can be measured. As a proof of concept, H₂¹⁸O was incorporated into a well characterized hemolysate model of sugar phosphate metabolism and ¹³C NMR was applied to quantify positional ¹⁸O enrichment of glucose‐6‐phosphate oxygens.

中文翻译：

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通过 13 C 同位素位移 NMR 信号观察到的红细胞裂解物将 H2 18 O 代谢并入特定的葡萄糖-6-磷酸氧中。

富含氧 18 (H ₂ ¹⁸ O) 的水是评估葡萄糖和糖原合成来源的潜在示踪剂，因为它通过特定的酶介导的交换/添加机制结合到 6-磷酸葡萄糖的特定位点。与² H不同，¹⁸ O 对这些过程中的任何一个都没有显着的同位素效应。因此，与氘化水相比，H ₂ ¹⁸ O 可能提供更精确的内源性碳水化合物合成估计值，前提是可以测量葡萄糖的位置¹⁸ O 富集。作为概念证明，H ₂ ¹⁸将 O 结合到一个充分表征的糖磷酸盐代谢的溶血模型中，并应用¹³ C NMR 来量化葡萄糖-6-磷酸氧的位置¹⁸ O 富集。