Development of new diagnosis for life-style diseases and elucidation its dynamics

建立了一种灵敏、选择性好的高效液相色谱-紫外检测唾液尿酸的分析方法。结果表明，尿酸(S/N=3)的检出限和定量限(S/N=10)分别为3 nM和0.1μM。7名受试者唾液尿酸浓度为134.5±103.3μ。尿囊素是尿酸酶与尿酸反应生成的嘌呤分解代谢产物。建立了一种准确、灵敏、选择性好的HILIC/MS测定人体生物样品中尿囊素的分析方法。尿囊素的检出限(S/N=3)为0.03，定量限(S/N=10)为0.1μM，内标平均回收率分别为96.9%(相对标准偏差：13.2%)、95.2%(相对标准偏差：9.0%)和100.3%(相对标准偏差：11.8%)。6名志愿者尿素、唾液和血清中尿囊素浓度分别为15.3~16 3μM、1.4 6~6.7μM和1.18~3.0 5μM。尿酸具有较强的清除自由基活性。尿酸与超氧阴离子和羟基自由基反应生成尿囊素。

A sensitive and selective analytical method for uric acid in saliva was developed by high-performance liquid chromatography with ultraviolet detector (HPLC-UV). The results showed that the detection limit and the quatificatiion limit (S/N = 10) of UA (S/N = 3) was 3 nM and 0.1μM, respectively. Concentrations of uric acid in the saliva of seven volunteers were 134.5±103.3μMAllantoin is a catabolic product of purines, which is formed by the enzymatic reaction of uricase with uric acid. An accurate, sensitive and selective analytical method for the determination of allantoin in human biological samples using hydrophllic interaction chromatography with mass spectrometly (HILIC/MS) was developed. The detection limit (S/N = 3) and the quatificatiion limit (S/N = 10) were 0.03 and 0.1 μM, respectively The average recoveries of allantoin with an internal standard in human serum, urine and saliva samples were 96.9% (RSD: 13.2%), 95.2% (RSD: 9,0%) and 100.3% (RSD: 11.8%), respectively. Concentrations of allantoin in the urea, saliva and serum of six volunteers were 15.3〜163 μM, 1.46〜6.7 μM and 1.18〜3.05 μM.Reactivity of uric acid and various free radicals as the biological oxidative stress were investigated by electron spin resonance (ESR). Uric acid had strong scavenging activity for free radicals. It was found that allantoin was produced by reaction of uric acid with superoxide anion and hydroxyl radical.