色氨酸及其主要代谢产物的分离和在生物样品中的测定

建立以乙酸缓冲系统和甲醇作流动相、电化学和紫外检测器联用的高效液相色谱法,分离和测定了色氨酸经5-羟色胺和犬尿酸原两条主要代谢途径的8种代谢物。使用三氯乙酸作离子对试剂以延长3-羟犬尿酸原的保留时间,分析了流动相pH值和三氯乙酸浓度对各物质分离的影响及检测条件。结果表明,pH值及三氯乙酸浓度对各物质保留时间有明显影响,可作为控制分离的主要因素。此外,对生物样品中各物质分离和检测条件进行了讨论。     

Determination and Application of Nineteen Monoamines in the Gut Microbiota Targeting Phenylalanine,Tryptophan, and Glutamic Acid Metabolic Pathways

It has been reported that monoamine neurotransmitters can be produced by gut microbiota, and that several related metabolites of amino acids in these pathways are associated with nervous system (NVS) diseases. Herein, we focused on three pathways, namely, phenylalanine (Phe), tryptophan (Trp), and glutamic acid (Glu), and established an underivatized liquid chromatography–tandem mass spectrometry (LC-MS/MS) method for the quantification of nineteen monoamine neurotransmitters and related metabolites in the gut microbiota. The neurotransmitters and related metabolites included Phe, tyrosine (Tyr), l-dopa (Dopa), dopamine (DA), 3-methoxytyramine, Trp, hydroxytryptophan, 5-hydroxytryptamine (5-HT), 5-hydroxyindole-3-acetic acid (5-HIAA), kynurenine (KN), kynurenic acid (KYNA), melatonin, tryptamine (TA), indole-3-lactic acid (ILA), indole-3-acetic acid (IAA), indolyl-3-propionic acid (IPA), Glu, gamma-aminobutyric acid (GABA), and acetylcholine (Ach). A fluoro-phenyl bonded column was used for separation, and the mobile phase consisted of methanol:acetonitrile (1:1) and water, with 0.2% formic acid in both phases. The compounds exhibited symmetric peak shapes and sufficient sensitivity under a total analysis time of 8.5 min. The method was fully validated with acceptable linearity, accuracy, precision, matrix effect, extraction recovery, and stability. The results showed that neurotransmitters, such as Dopa, DA, 5-HT, GABA, and Ach, were present in the gut microbiota. The metabolic pathway of Trp was disordered under depression, with lower levels of 5-HT, 5-HIAA, KN, KYNA, TA, ILA, IAA, IPA, and Glu, and a higher ratio of KYNA/KN. In addition, some first-line NVS drugs, such as sertraline, imipramine, and chlorpromazine, showed regulatory potential on these pathways in the gut microbiota.     

Ultrasensitive detection of indoleamines by combination of nanoparticle-based extraction with capillary electrophoresis/laser-induced native fluorescence

For the first time, citrate-capped gold nanoparticles (citrate-AuNPs) have been used for the selective extraction of indoleamines – 5-hydroxytryptophan (5-HTP), tryptophan (Trp), tryptamine (TA), 5-hydroxytryptamine (5-HT), and 5-hydroxyindoleacetic acid (5-HIAA) – prior to their analysis by capillary electrophoresis/laser-induced native fluorescence (CE/LINF). The extinction spectra obtained for the citrate-AuNPs in the presence of indoleamines revealed that 5-HTP, 5-HT, and 5-HIAA were extracted mainly because of van der Waals interactions between the indole ring and the citrate-AuNPs (hydrophobic surface), while 5-HT and TA were extracted by electrostatic attractions between the amine group of the indoleamines and the citrate ligands adsorbed on the AuNP surface. The extracted indoleamines could be liberated from the AuNP surface by the addition of high concentrations of 2-mercaptoethanol (2-ME), which binds strongly to the AuNPs. The sensitivity of this method to indoleamines could be significantly enhanced by increasing the AuNP concentration, incubation time, and sample volume. Under optimal extraction and separation conditions, the combination of NP-based extraction and CE-LINF provided 48-, 4077-, 985-, 920-, and 4030-fold improvements in the limits of detection (signal-to-noise ratio of 3) for 5-HTP, Trp, TA, 5-HT, and 5-HIAA as compared to the analysis of five indoleamines by CE-LINF. In addition, this proposed method was successfully used for the determination of TA and 5-HT in urine.     

超高效液相色谱-串联质谱法定量分析尿液中色氨酸及其代谢产物

基于超高效液相色谱-串联质谱(UPLC-MS/MS)建立定量分析色氨酸(Trp)及代谢产物3-OH-犬尿氨酸(3-OH-Kyn)、3-OH-邻氨基苯甲酸(3-OH-AA)、黄尿酸(XA)、犬尿氨酸(Kyn)、5-羟基吲哚乙酸(5-HIAA)、犬尿喹啉酸(KA)和5-羟色胺(5-HT)的方法,应用该方法分析其在尿样中的含量,探讨排泄规律。将尿样稀释、离心后,加入丹磺酰氯(DNS-Cl)衍生,经Thermo C₁₈色谱柱(50 mm×3 mm, 2.7 μm)分离和0.1%甲酸和甲醇梯度洗脱后,采用电喷雾电离(ESI)源,在正离子扫描和多反应监测(MRM)模式下检测。以咖啡酸(CA)为内标,定量分析。结果显示,8种目标化合物的线性关系良好,相关系数(R ²)≥0.9740,检测灵敏(LOD为0.005~0.5 ng/mL),回收率高(93.24%~107.65%)。采用本方法检测分析了健康志愿者70个尿液样本,在尿样中检测到Trp原型及其7种代谢产物。结果表明,体内的Trp是通过原型和代谢两种方式排泄:Trp原型的含量为5.22~20.88 μg/mL;尿液中经代谢后排泄的Trp量是原型的124%~268%,即体内的Trp主要经代谢后排出体外。方法主要研究了Trp-5-HT和Trp-Kyn两条途径的代谢产物含量,Trp经Kyn降解生成的3-OH-AA和3-OH-Kyn含量较多,即Trp-Kyn是体内Trp的主要代谢途径。方法通过UPLC-MS/MS实现了尿液中Trp及其代谢产物含量的检测,能为临床检查提供技术和理论支持。     

Electrochemical behavior of tryptophan and its derivatives at a glassy carbon electrode modified with hemin

The electrochemical behavior of tryptophan (Trp) and its derivatives, such as indole-3-acetic acid (IAA), 5-hydroxytryptamine (5-HT), 5-hydroxy-indole-3-acetic acid (5-HIAA) and glycyl-tryptophan (Gly-Trp) peptide at a glassy carbon electrode modified with hemin (hemin/GC electrode) by electropolymerization have been investigated in detail. The results showed that the hemin/GC electrode would catalyze the electrochemical oxidation of Trp and its derivatives, based on which a differential pulse voltammetric procedure has been proposed for determination of Trp and its derivatives. Meanwhile, the electrochemical reaction mechanism for these compounds at hemin/GC electrode has been also investigated, and the results indicated that a two electron and two proton transfer was involved in the electrode reaction process.     

鼠脑组织中6-羟基-1-甲基-1,2,3,4-四氢-β-咔啉及其相关生物胺的高效液相色谱-电化学检测

建立了大鼠脑组织中6-羟基-1-甲基-1,2,3,4-四氢-β-咔啉(6-OH-MTHβC)、5-羟色胺(5-HT)和5-羟吲哚乙酸(5-HIAA)含量的高效液相色谱-库仑阵列电化学检测(HPLC-ECD)方法。采用的色谱柱为DiscoveryHS F5柱(250 mm×4.6 mm,5 μm),流动相为缓冲液（40 mmol/L柠檬酸+20 mmol/L磷酸氢二钠+0.3 mmol/L乙二胺四乙酸二钠,pH 4.0）-甲醇（体积比为78∶22）混合液,流速为1 mL/min。6-OH-MTHβC、5-HT、5-HIAA在1.0～500.0 μg/L范围内线性关系良好(r>0.9992),检出限分别为0.56,0.26,0.53 μg/L,日内和日间精密度(以相对标准偏差表示)均低于6.1%,回收率分别为87.1%～98.2%,87.0%～95.3%,90.1%～97.7%。用该方法检测新生7 d的SD胎鼠脑内6-OH-MTHβC及5-HT、5-HIAA的含量,发现SD胎鼠在急性酒精中毒8 h后6-OH-MTHβC显著上升(P<0.05);而5-HT和5-HIAA的含量有所下降,但无显著性差异。该法简便、稳定、灵敏度高,适用于测定鼠脑组织中6-OH-MTHβC和5-HT,5-HIAA含量的相关研究。     

高效液相色谱-程序波长紫外检测法同时测定血浆中的色氨酸及其代谢物

建立了一种高效液相色谱-程序波长紫外检测法同时测定血浆中色氨酸(Trp)及其主要代谢产物犬尿氨酸(Kyn)和5-羟色胺(5-HT)。以茶碱为内标(IS),采用BDS-Hypersil-C8柱(150 mm×4.6 mm, 5 μm)分离。流动相为10 mmol/L醋酸钠缓冲液(pH 4.5)-乙腈(94:6, v/v),流速为0.6 mL/min;柱温为25 ℃;紫外检测波长设定: Kyn和IS为360 nm, 5-HT为220 nm, Trp为302 nm。3种物质的平均回收率为87%～113%;线性范围分别为3.97～400 μmol/L(Trp), 0.421～20.2 μmol/L(Kyn), 4.36～980 nmol/L(5-HT);检出限分别为0.134 μmol/L(Trp), 0.0160 μmol/L(Kyn), 2.03 nmol/L(5-HT)。利用该方法对15例抑郁症患者和15例健康志愿者的血浆进行测定,结果表明两组间Trp的代谢存在显著的差异。     

Quantitative analysis of multiple urinary biomarkers of carcinoid tumors through gold-nanoparticle-assisted laser desorption/ionization time-of-flight mass spectrometry

A simple technique for quantitative analysis of four urinary biomarkers, tryptophan (TRP), 5-hydroxytryptophan (5-HTP), 5-hydroxytryptamine (5-HT) and 5-hydroxyindole acetic acid (5-HIAA) of carcinoid tumors is developed using gold nanoparticles as the assisted matrix in surface-assisted laser desorption/ionization time-of-flight mass spectrometry (SALDI–TOF MS). The optimal SALDI conditions for the efficient ionization of those biomarkers are systematically explored by the adjustments of the concentrations of gold nanoparticles and internal standards. The mass spectra with strong signals and minimal background noise are obtained using 1-naphthaleneacetamide (NAD) as the internal standard. The calibration curves of the biomarker concentrations are determined using SALDI–TOF MS and the high linearity is obtained in all samples. For future clinical testing, multiplexed detection of those biomarkers in the urine samples of healthy males is performed. The successful quantitative detections of TRP, 5-HTP, 5-HT and 5-HIAA indicate that our technique provided great potentials to be developed a simple and rapid platform for the tumor biomarker detections.     

聚(3-氨基-5-巯基-1,2,4-三唑)/多壁碳纳米管修饰的玻碳电极同时检测尿酸、黄嘌呤与次黄嘌呤

采用滴涂法得到多壁碳纳米管(MWCNTs)修饰的玻碳电极(GCE),通过电沉积方法将3-氨基-5-巯基-1,2,4-三唑(TA)沉积在MWCNTs/GCE表面,制备了聚(3-氨基-5-巯基-1,2,4-三唑)/多壁碳纳米管修饰电极(p TA/MWCNTs/GCE)。采用循环伏安法(CV)和示差脉冲伏安法(DPV),研究了尿酸(UA)、黄嘌呤(XA)和次黄嘌呤(HX)在该修饰电极上的电化学行为。结果表明,该修饰电极对UA、XA和HX均有较好的电催化活性作用,能实现对3种物质的同时测定。UA、XA和HX在该修饰电极上的线性范围分别为9.0~739.0、2.0~259.0、1.0~353.0μmol/L;检出限分别为0.67、0.17、0.33μmol/L。该修饰电极已成功用于尿液和血清实际样品中UA、XA和HX的同时测定,回收率为98.8%~105.5%。     

Electrocatalytic Oxidation and Simultaneous Determination of Uric Acid,Xanthine, Hypoxanthine and Dopamine Based on β-Cyclodextrin Modified Glassy Carbon Electrode

A novel covalently modified glassy carbon electrode with β-cyclodextrin was prepared via electropolymerization technique for the simultaneous determination of uric acid(UA), xanthine(XA), hypoxanthine(HX) and dopamine(DA). This new electrode presented an excellent electrocatalytic activity towards the oxidation of UA, XA, HX and DA by cyclic voltammetry(CV) method. The oxidation peaks of the four compounds were well defined and had the enhanced peak currents. The separation potentials of the oxidation peaks for DA-UA, UA-XA and XA-HX were 150, 390 and 360 mV in CV, respectively. By means of differential pulse voltammetry(DPV) method, the calibration curves in the ranges of 10-225, 5-105, 10-170 and 5-150 μmol/L were obtained for UA, XA, HX and DA, respectively. The lowest detection limits(S/N=3) were 5, 1.25, 5 and 1.5 μmol/L for UA, XA, HX and DA, respectively. The practical application of the modified electrode was demonstrated by the determination of DA in hydrochloride injection and UA, XA, HX in human urine samples.     

Simultaneous determination of uric acid, xanthine and hypoxanthine at poly(pyrocatechol violet)/functionalized multi-walled carbon nanotubes composite film modified electrode

A sensitive and selective electrochemical method was developed for simultaneous determination of uric acid (UA), xanthine (XA) and hypoxanthine (HX) based on a poly (pyrocatechol violet)/carboxyl functionalized multi-walled carbon nanotubes composite film modified electrode. The preparation and basic electrochemical performance of the novel composite film modified glassy carbon electrode were investigated in details. The electrochemical behaviors of UA, XA and HX at the modified electrode were studied by cyclic voltammetry. The results showed that this new electrochemical sensor exhibited excellent electrocatalytic activity towards the oxidation of the three analytes. The mechanism of catalysis was discussed. The anodic peaks of the three species were well defined with lowered oxidation potential and enhanced oxidation peak currents, so the modified electrode was used for simultaneous voltammetric measurement of UA, XA and HX by differential pulse voltammetry. Under the optimum conditions, the detection limits were 0.16 μmol L(-1) for UA, 0.05 μmol L(-1) for XA and 0.20 μmol L(-1) for HX, respectively (S/N of 3). The proposed method has been successfully applied to simultaneous determination of UA, XA and HX in human serum samples.     

Application of a novel micro-injector in the determination of indole derivatives in the rat pineal gland by capillary electrophoresis with electrochemical detection

A novel micro-injector has been fabricated for capillary electrophoresis (CE). It was successfully used for the determination of some indole derivatives for example melatonin (MT), serotonin (5-HT), tryptophan (Trp), and 5-hydroxy-tryptophane (5-HTrp) in the rat pineal gland by capillary electrophoresis with electrochemical detection (CE-EC). CE was performed in 0.20 mol L(-1) phosphate buffer (pH 8.0). The compounds investigated can be well separated and detected within 15 min. The working electrode used was a 300-microm diameter carbon electrode positioned opposite the outlet of the capillary. The relationship between peak current and analyte concentration was highly linear in the range from 0.10 to 500 micromol L(-1); detection limits (S/N = 3) were 0.03-0.13 micromol L(-1). The proposed method has been successfully used to analyze real biological samples.     

高效液相色谱-荧光检测法测定血清中的犬尿氨酸

建立了高效液相色谱-荧光检测(HPLC-FLD)测定血清中犬尿氨酸(kynurenine,Kyn)含量的方法。采用Hypersil C8色谱柱(300 mm×6.0 mm,10 μm), 流动相为0.25 mol/L醋酸锌及50 mmol/L醋酸溶液(含3%乙腈),流速为1.5 mL/min, 荧光检测激发波长和发射波长分别为365 nm和480 nm。血清标本经5%(v/v)高氯酸溶液去除蛋白质后取上层清液直接进样, Kyn经流动相等度洗脱分离后,用FLD进行测定。研究结果表明Kyn保留时间约为8.3 min,线性范围为0.098～19.6 μmol/L,最低检出浓度为0.04 μmol/L,回收率为90.8%～96.2%,日内、日间测定的相对标准偏差均小于5%,苯丙氨酸、酪氨酸、色氨酸、5-羟色胺和犬尿喹啉酸等物质对犬尿氨酸的测定均无干扰。建立的方法简便、快速、灵敏、特异,适用于临床和科研应用。     

聚咪唑/氮化碳新型纳米复合材料修饰电极对尿酸、黄嘌呤和次黄嘌呤的同时检测

以三聚氰胺为原料, 采用热聚合法合成了类石墨烯状二维片状氮化碳(g-C₃N₄)纳米材料; 通过电沉积和高电位氧化的方法制得氧化聚咪唑(PImox)/g-C₃N₄修饰电极(PImox/g-C₃N₄/GCE). 采用扫描电子显微镜(SEM)和X射线粉末衍射仪(XRD)对g-C₃N₄纳米材料进行了表征; 通过循环伏安法(CV)和差分脉冲伏安法(DPV)考察了尿酸(UA)、 黄嘌呤(XA)和次黄嘌呤(HX)在该电极上的电化学行为. 结果表明, UA, XA和HX的检测线性范围分别为2.0~216.0, 5.0~542.0和5.0~778.0 μmol/L; 检出限分别为0.17, 0.30和0.30 μmol/L. 将该修饰电极用于实际样品(血清和尿液)中UA, XA和HX的同时测定, 加标回收率为98.4%~105.2%.     

Simultaneous determination of 5-hydroxytryptamine, its amino acid precursors and acid metabolite in discrete brain regions by high-performance liquid chromatography with fluorescence detection

L-Tryptophan, 5-hydroxytryptophan (5-HTP), 5-hydroxytryptamine, and 5-hydroxyindoleacetic acid (5-HIAA) from discrete regions of brain can be resolved by isocratic elution on a C-18 reversed-phase column and quantitated by native fluorescence measurement. This method is rapid and simple and can reproduceably detect 5-hydroxytryptamine, tryptophan and 5-HIAA with picogram sensitivity. The detection of 5-HTP in brain extracts from untreated animals is difficult because of the extremely low endogenous levels of 5-HTP. Quantitation of 5-HTP presents no problem in animals injected with 5-HTP or with an inhibitor of L-aromatic amino acid decarboxylase. Brain tissue requires minimal treatment for assay and the hydroxyindoles are stable enough to allow automated processing.     

Simultaneous determination of serotonin and 5-hydroxyindole-3-acetic acid in human urine by automated precolumn derivatization and semi-microbore column liquid chromatography with fluorescence detection.

An improved high-performance liquid-chromatographic (HPLC) assay for the simultaneous determination of serotonin (5-HT) and 5-hydroxyindole-3-acetic acid (5-HIAA) in human urine is reported. Following the automated precolumn derivatization of urinary 5-HT and 5-HIAA with benzylamine, the derivatives are separated by isocratic elution on a reversed-phase C18 semi-microbore column, and are fluorometrically detected at an excitation wavelength of 345 nm and an emission wavelength of 480 nm. The detection limits of 5-HT and 5-HIAA are 7 and 5 nmol/l in urine (0.7 and 0.5 fmol/20-microl injection). The proposed automatic method permits a highly selective and sensitive determination of 5-HT and 5-HIAA in human urine without any sample purification.     

Simultaneous determination of dopamine and serotonin by use of covalent modification of 5-hydroxytryptophan on glassy carbon electrode

An electrochemical biosensor was fabricated by covalent modification of 5-hydroxytryptophan (5-HTP) on the surface of glassy carbon electrode (GCE). The electrode, denoted as 5-HTP/GCE, was characterized by X-ray photoelectron spectroscopy, cyclic voltammetry and differential pulse voltammetry. For comparison, tryptophan modified GCE (TRP/GCE) and serotonin modified GCE (5-HT/GCE) were prepared by the same method. It was found that electrocatalytic ability of these electrodes was in the order of 5-HTP/GCE?>?TRP/GCE?>?5-HT/GCE for the oxidation of dopamine (DA) and 5-HT. The sensor was effective to simultaneously determine DA and 5-HT in a mixture. It can resolve the overlapping anodic peaks into two well-defined voltammetric peaks at 0.24 and 0.39 V (versus SCE). The linear response is in the range of 5.0?×?10^?7–3.5?×?10^?5 mol L^?1 with a detection limit of 3.1?×?10^?7 mol L^?1 for DA, and in the range of 5.0?×?10^?6–3.5?×?10^?5 mol L^?1 with a detection limit of 1.7?×?10^?6 mol L^?1 for 5-HT (s/n?=?3), respectively.     

在线衍生-高效液相色谱法同时测定血浆中的色氨酸及其代谢物

建立了醋酸锌在线衍生高效液相色谱法同时测定血浆中色氨酸(Trp)、犬尿氨酸(Kyn)、5-羟吲哚乙酸(5-Hiaa)和犬尿喹啉酸(Kyna)的方法。以3-硝基酪氨酸为内标(IS),采用Hypersil C-18柱(250 mm×4.0 mm, 5 μ m),以250 mmol/L醋酸锌溶液(pH 5.5)-乙腈(95:5, v/v)为流动相,流速为0.8 mL/min,柱温30℃。荧光检测波长设定:5-Hiaa为278 nm(λ_ex)/343 nm(λ_em), Kyna为244 nm(λ_ex)/400 nm(λ_em);紫外检测波长设定:Kyn和IS为360 nm, Trp为302 nm。4种物质的回收率在91.62%~114.17%之间;线性范围分别为2.50~320.00 μ mol/L(Trp), 0.32~15.36 μ mol/L(Kyn), 3.27~104.60 nmol/L(5-Hiaa), 14.00~464.80 nmol/L(Kyna);检出限分别为0.078 μ mol/L(Trp), 0.056 μ mol/L(Kyn), 0.690 nmol/L(5-Hiaa), 1.290 nmol/L(Kyna)。利用该方法对30例正常孕妇和28例女性健康志愿者的血浆进行测定,结果表明两组间Trp, Kyn和Kyna含量有显著性差异。该方法操作简便,重复性好,灵敏度高,适合于临床检测。     

高效液相色谱-串联质谱法测定兔尿中溴氰菊酯及其毒性生物标志物

建立了一种应用高效液相色谱-串联质谱（HPLC-MS/MS）测定兔尿中与溴氰菊酯毒性相关的多种生物标志物的检测方法。分析物包括溴氰菊酯及其代谢产物1R,3R-二溴菊酸、3-苯氧基苯甲酸,以及5种生物标志物5-羟色胺、5-羟基吲哚乙酸、3-硝基丙酸、8-羟基脱氧鸟苷和6-甲氧基鸟嘌呤。样品经硅藻土基质固相分散萃取、三氯乙酸沉淀蛋白质和HLB固相萃取小柱净化,使用电喷雾离子源,在多反应监测模式下正负切换采集测定,其中溴氰菊酯、5-羟色胺、5-羟基吲哚乙酸、8-羟基脱氧鸟苷和6-甲氧基鸟嘌呤采用正离子模式,1R,3R-二溴菊酸、3-苯氧基苯甲酸和3-硝基丙酸采用负离子模式。基质校准曲线外标法定量。结果表明,7种生物标志物在各自的浓度范围内线性关系良好（R²不小于0.9914）,5-羟基吲哚乙酸的检出限和定量限分别为20 μg/L和50 μg/L,其余化合物的检出限和定量限分别为0.2~5.0 μg/L和0.5~10 μg/L;在兔尿中3个不同添加水平的平均回收率为74.2%~98.7%,相对标准偏差（RSD）不大于12%,方法简单、快速、准确、灵敏,可作为溴氰菊酯暴露评估的检测方法。     

高效液相色谱-荧光检测法同时测定血清中的犬尿氨酸和犬尿喹啉酸

建立了在线衍生、双波长高效液相色谱-荧光检测器同时检测血清中犬尿氨酸(kynurenine, Kyn)和犬尿喹啉酸(kynurenic acid, KYNA)含量的方法。血清标本经5%高氯酸溶液去除蛋白质后,上清液直接进样分析测定。采用的色谱柱为Hypersil C8柱;流动相为0.25 mol/L醋酸锌-50 mmol/L醋酸溶液(含3%乙腈),流速为1.5 mL/min。在0～10 min时间段,在激发波长和发射波长分别为365 nm和480 nm时检测Kyn;10 min后,在激发波长和发射波长分别变换为344 nm和404 nm时检测KYNA。Kyn的保留时间约为8.1 min,线性范围为98～19600 nmol/L,最低检出浓度为50 nmol/L,平均回收率为94.88%,日内、日间测定值的相对标准偏差(RSD)均低于4%。KYNA的保留时间约为13.0 min,线性范围为2.62～1047 nmol/L,最低检出浓度为0.11 nmol/L,平均回收率为102.72%,日内、日间测定的RSD均低于4%。苯丙氨酸、酪氨酸、色氨酸和5-羟色胺等物质对目标物的检测无干扰。71例健康成人血清中,Kyn和KYNA含量分别为(1.40±0.34) μmol/L和(24.22±8.67) nmol/L。该方法简便、快速、灵敏、特异,适于临床和科研应用。