Rapid Profiling of Alkaloids in Several Medicinal Herbs by Matrix-assisted Laser Desorption/Ionization Mass Spectrometry

A simple method was developed for rapid and direct profiling of alkaloids in medical herbs via matrix-assisted laser desorption/ionization time-of-flight mass spectrometry（MALDI-TOF MS）. The dry herbs were first ground to powder and passed through a stainless steel sieve, mixed with the matrix solution to form a homogeneous suspension, which was then directly applied to MALDI analysis. Several matrices were investigated and 2,5- dihydroxybenzoic acid（DHB） was chosen as the optimized one, and the particle with small size was found to favor the analysis. Using this method, the profiles of alkaloids in several medical herbs were readily obtained, and the toxicities of crude and processed Radix Aconiti Lateralis Preparata were compared via the relative intensities of the peaks of the corresponding toxic components shown in their MALDI spectra. This method therefore provides a rapid and reliable protocol for obtaining profiles of alkaloids in medical herbs by using MALDI-TOF MS.

Analysis of Single Nucleotide Polymorphism in Human Paraoxonase 1 Gene(Q192R) with Matrix-assisted Laser Desorption/Ionization Time-of-flight Mass Spectrometry

Introduction Single nucleotide polymorphisms （SNPs） are the most abundant DNA markers in the human genome occurring at a frequency of one in every 500--1000 nucleotides. A variety of methods have been used for the analysis of single nucleotide polymorphisms, including restriction fragment length polymorphism （RFLP）, direct sequencing by using laser-induced fluorescence detectionTM, fluorescence energy transfer, MALDI-TOF MS combined with primer extension or invasive cleavage, and fluorescence polarization. During the past two decades, mass spectrometry has become a very popular tool in the analysis of biomolecules and is perfectly suited to the analysis of single nucleotide polymorphisms （SNPs） due to its speed, low cost, and accuracy. In this work, we used MALDI TOF mass spectrometry to detect the fragments of restriction endonuclease hydrolysis of PCR products flanking a SNP located at paraoxonase 1（Q192R）. Compared with electrophoresis, this method requires less time of analysis and possess a higher accuracy.

A novel sample preparation method of matrix-assisted laser desorption/ionization time of flight mass spectrometry for polystyrene

A novel sample preparation method of matrix-assisted laser desorption/ionization mass spectrometry for polystyrene was reported. Compared to the conventional dried-droplet method, the efficiency of ionization and signal intensity of mass spectra were improved. The mechanism was also analyzed.

MicrobMatcher: a microbial comparison software based on matrix-assisted laser desorption/ionization with time-of-flight mass spectrometry

Matrix-assisted Laser Desorption/Ionization with Time-of-flight Mass Spectrometry (MALDI-TOFMS) was investigated as a method for the rapid identifica-tion of species. Current demand in microbial identi-fication is how to compare unknown strains to the known one quickly, semi-automatically and accurately. In this paper, we present a software tool that allows flexibly microbial matching in a user-friendly way, by letting the users to customize comparison parameters including: in vitro transcription enzyme, mass tolerance,minimum fragment length, intensity threshold and corresponding weights. We provide three spectral scoring functions to compute the affin-ity between the species. Therefore, the precision of microbial comparison increases. To test and verify this tool, we employed experimental spectral data based on MALDI-TOFMS and the gene sequences of E.coli and Salmonella. This software is written in Java for cross-platform intention.

MALDI-TOF MS技术在临床微生物检验中的应用

随着科学技术的发展,新技术在医学检验中的应用越来越广泛。相较于传统微生物鉴定繁琐、耗时的工作流程,基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS,简称MS)技术因其快速、灵敏、简便、省时和特异性高等特点,在菌种鉴定、耐药监测、突变菌株鉴别等方面发挥巨大的作用,逐渐成为临床微生物实验室不可或缺的微生物鉴定工具。虽然MS技术鉴定菌种高度依赖数据库,也在一定程度上受限于临床样本质量,但其在临床微生物检验中仍有较大的空间待开发。文章对MS技术在临床微生物检验中的应用进行综述。

MALDI-TOF MS直接靶板微滴生长测定法在CRKP快速检测中的应用

目的探讨基于基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)的直接靶板微滴生长测定(DOT-MGA)法快速筛查碳青霉烯类耐药肺炎克雷伯菌(CRKP)的准确性和临床应用价值。方法收集2020—2021年连云港市第一人民医院肺炎克雷伯菌临床分离株251株,其中美罗培南敏感123株,CRKP128株。采用DOT-MGA法对4和6μL 2种取样量的所有菌株进行美罗培南耐药性检测。采用微量肉汤稀释法测定菌株的美罗培南最小抑菌浓度(MIC)。以微量肉汤稀释法耐药性分析结果为标准,评价DOT-MGA法耐药性检测结果的准确性。结果以微量肉汤稀释法为标准,孵育生长4 h后,DOT-MGA法2种取样量的敏感性和阴性预测值均为100.0%,其中4μL取样量检测CRKP的特异性为92.5%,阳性预测值为92.8%;6μL取样量检测CRKP的特异性为89.8%,阳性预测值为90.1%。123株美罗培南敏感株的美罗培南MIC_(50)为0.125μg·mL^(-1),MIC_(90)为0.25μg·mL^(-1);128株美罗培南耐药株的MIC_(50)和MIC_(90)均为≥128μg·mL^(-1)。DOT-MGA法与微量肉汤稀释法的一致性分析结果显示,4μL加样量Kappa值为0.88,6μL加样量Kappa值为0.83。结论基于MALDITOF MS的DOT-MGA法筛查CRKP具有较高的准确性,且简便、快捷,可用于快速检测CRKP。

MALDI-TOF MS法快速鉴定散装即食食品中3种食源性致病菌

本研究旨在利用基质辅助激光解吸电离飞行时间质谱法(Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry,MALDI-TOF MS)快速检测并鉴定散装即食食品中的沙门氏菌、金黄色葡萄球菌和蜡样芽孢杆菌3种食源性致病菌。通过对点样方式、前处理方式、不同培养基及培养时间等各项实验条件的优化筛选确定最佳方法,并考察其检测限和稳定性,同时用所建立的方法与多重PCR法、VITEK 2等生化鉴定法进行结果比对,比较三者鉴定结果的一致性,最后进行批量食品样本检测来探寻MALDI-TOF MS鉴定法在散装即食食品中的适用性。结果表明,三种目标菌同一批次及不同传代次数的鉴定得分均大于95%,变异系数均小于2%,所建立的方法重复性和稳定性良好,且检测限为10^(5)CFU/mL,MALDI-TOF MS菌株鉴定结果与多重PCR法、生化鉴定法结果高度一致,且比二者检测用时更短,更加特异高效;在点样方式上,相较于夹心法与混合干滴法,三种覆盖法点样平均鉴定得分更高,均为99.9%,其中1μL+1μL覆盖法点样可获得的平均峰数目更多,特征峰更复杂且强度更高;而在前处理方式上,甲酸乙腈法与其他两种菌体处理方法相比可获得更多的出峰量和更高的峰强度,平均鉴定得分均在98%以上,且与数据库中图谱匹配度更高。综上所述,MALDI-TOF MS法在致病菌鉴定方面不仅灵敏特异、准确快速,且操作简便、结果直观,作为国标法的有力补充,为食源性致病菌的分析鉴定与分型溯源提供了新思路。

Detection of lung adenocarcinoma using magnetic beads based matrix-assisted laser desorption/ionization time-of-flight mass spectrometry serum protein profiling

Background Recently, due to the rapid development of proteomic techniques, great advance has been made in many scientific fields. We aimed to use magnetic beads （liquid chip） based matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS） technology to screen distinctive biomarkers for lung adenocarcinoma （adCA）, and to establish the diagnostic protein profiles. Methods Using weak cation exchange magnetic beads （MB-WCX） to isolate and purify low molecular weight proteins from sera of 35 lung adCA, 46 benign lung diseases （BLDs） and 44 healthy individuals. The resulting spectra gained by anchor chip-MALDI-TOF-MS were analyzed by ClinProTools and a pattern recognition genetic algorithm （GA）. Results In the working mass range of 800-10 000 Da, 99 distinctive peaks were resolved in lung adCA versus BLDs, while 101 peaks were resolved in lung adCA versus healthy persons. The profile gained by GA that could distinguish adCA from BLDs was comprised of 4053.88, 4209.57 and 3883.33 Da with sensitivity of 80%, specificity of 93%, while that could separate adCA from healthy control was comprised of 2951.83 Da and 4209.73 Da with sensitivity of 94%, specificity of 95%. The sensitivity provided by carcinoembryonic antigen （CEA） in this experiment was significantly lower than our discriminatory profiles （P 〈0.005）. We further identified a eukaryotic peptide chain release factor GTP-binding subunit （eRF3b） （4209 Da） and a complement C3f （1865 Da） that may serve as candidate biomarkers for lung adCA. Conclusion Magnetic beads based MALDI-TOF-MS technology can rapidly and effectively screen distinctive proteins/polypeptides from sera of lung adCA patients and controls, which has potential value for establishing a new diagnostic method for lung adCA.

核酸MALDI-TOF MS检测在肺结核诊断中的价值

目的探讨基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)在疑似肺结核(PTB)诊断中的应用价值及其阳性结果的影响因素,以期为临床治疗提供参考。方法选取甘肃省第二人民医院(西北民族大学附属医院)2022年8月—2023年3月收治的疑似PTB患者77例为研究对象。所有患者肺泡灌洗液(BALF)均接受MALDI-TOF MS检测和结核分枝杆菌(MTB)培养。根据MTB培养结果,对核酸MALDI-TOF MS检测进行诊断效能分析,并探讨核酸MALDI-TOF MS检测阳性的影响因素。结果核酸MALDI-TOF MS检测结果显示,MTB阳性共37例(48.1%,37/77),40例阴性(51.9%,40/77)。以培养结果为金标准,核酸MALDI-TOF MS的灵敏度、特异度、阳性预测值(PPV)、阴性预测值(NPV)和准确度分别为90.9%、84.1%、81.1%、92.5%和87.0%,采用Kappa检验法评价核酸MALDI-TOF MS检测和MTB培养法的一致性,结果显示Kappa值为0.739(P<0.05)。2组患者在是否有糖尿病、身体质量指数(BMI)及降钙素原(PCT)方面比较,差异均有统计学意义(P<0.05)。多因素Logistic回归分析结果显示:有糖尿病和PCT异常为核酸MALDITOF MS阳性的独立危险因素(P<0.05)。结论核酸MALDI-TOF MS检测对PTB的早期诊断具有重要价值,可为患者的规范用药提供更好的指导,即为患者的治疗制定更为精准、有效的治疗方案,从而提高治疗效果、改善患者生活质量。

MALDI coupled with laser-postionization and trapped ion mobility spectrometry contribute to the enhanced detection of lipids in cancer cell spheroids

Cancer cell spheroids(CCS) are a valuable three-dimensional cell model in cancer studies because they could replicate numerous characteristics of solid tumors. Increasing researches have used matrix-assisted laser desorption/ionization mass spectrometry imaging(MALDI-MSI) to investigate the spatial distribution of endogenous compounds(e.g., lipids) in CCS. However, only limited lipid species can be detected owing to a low ion yield by using MALDI. Besides, it is still challenging to fully characterize the structural diversity of lipids due to the existence of isomeric/isobaric species. Here, we carried out the initial application of MALDI coupled with laser-postionization(MALDI-2) and trapped ion mobility spectrometry(TIMS) imaging in HCT116 colon CCS to address these challenges. We demonstrated that MALDI-2 is capable of detecting more number and classes of lipids in HCT116 colon CCS with higher signal intensities than MALDI. TIMS could successfully separate numerous isobaric/isomeric species of lipids in CCS. Interestingly, we found that some isomeric/isobaric species have totally different spatial distributions in colon CCS. Further MS/MS imaging analysis was employed to determine the compositions of fatty acid chains for isomeric species by examining disparities in signal intensities and spatial distributions of product ions. This work stresses the robust ability of TIMS and MALDI-2 imaging in analyzing endogenous lipids in CCS, which could potentially become powerful tools for future cancer studies.

Autof ms 1000与MALDI Biotyper对临床常见丝状病原真菌鉴定的比较分析

目的:研究比较两种基质辅助激光解吸电离飞行时间质谱仪(Autof ms 1000与MALDI Biotyper)对临床常见丝状病原真菌鉴定的准确性和效率。方法:共纳入32株丝状病原真菌标准菌株和120株临床分离菌株,按照标准操作方法分别用Autof ms 1000与MALDI Biotyper对相关菌株进行鉴定,对相关结果及测序分子鉴定结果进行对比分析。结果:在种水平上,Autof ms 1000质谱仪共检出140株丝状病原真菌,检出正确率为92.1%(140/152),其中126株分值在9.0以上,2株出现错误鉴定,误鉴定比例为1.3%(2/152);MALDI Biotyper质谱仪共正确检出98株,检出正确率为64.4%,2.0分以上的菌株47株,仅3株鉴定分值大于2.3分,7株出现误鉴定。结论:Autof ms 1000与MALDI Biotyper这两种质谱鉴定系统均能用于临床常见丝状病原真菌的快速鉴定,而Autof ms 1000质谱仪更具优势。

Matrix-assisted laser desorption/ionization time of flight mass spectrometry in the genetic basis of systemic lupus erythematosus and the complicating kidney injury

Background It is necessary to develop some innovative methods to reveal and discover the novel （SLE）-related protein molecules. In the present study, matrix-assisted laser desorption/ionization time of flight mass spectrometry （MALDI- TOF MS） was employed to detect the differential expression of serum polypeptides in the patients with systemic lupus erythematosus （SLE） presenting with a family history or complicating with kidney injury so as to identify the proteins associated with the genetic factors and kidney injury in SLE. Methods The subjects recruited were divided into four groups, that is, a group of SLE patients with both family history and kidney injury, a group of SLE patients with only kidney injury but no family history, a group of SLE patients with neither family history nor kidney injury, and a control group consisting of healthy volunteers. By adopting MALDI-TOF MS analysis, the serum samples obtained from the three groups of SLE patients were examined and compared with those from the control group; the categorized peptide fingerprint profile was established via the biological data collected from the samples. Results The expression of protein with a mlz of 4207 Da increased significantly in SLE patients; the protein with a ml z of 2658 Da was expressed in all SLE patients; three proteins （with mlz of 1465, 5332, and 5900 Da respectively） were expressed in the SLE patients complicated with kidney injury and the protein with a mlz of 1943 Da was expressed in SLE patients with family history. Conclusion A number of differential proteins were successfully detected and identified through MALDI-TOF MS detection and these proteins may be associated with the genetic basis of SLE and the complicating kidney injury.

MALDI-TOF-MS技术在肉芽肿性乳腺炎脓液棒状杆菌检测中的应用研究

目的:研究拟通过基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)技术在脓液克氏棒状杆菌(CK)鉴定过程中的应用探索,为临床微生物实验室对CK的准确鉴定提供帮助。方法:无菌条件下分别采集2019年1月-2021年7月镇江市妇幼保健院乳腺科门诊及病房30例经病理确诊为肉芽肿性乳腺炎(GM)患者手术中获取的新鲜脓肿穿刺液标本,用于细菌、真菌、结核菌涂片检查及需氧菌、厌氧菌培养。结果:采用梅里埃VITEK2compact全自动细菌鉴定仪进行生化鉴定,结果表明,23株菌鉴定为CK,其余7株菌均鉴定失败或错误。布鲁克MALDIBiotyper质谱仪鉴定结果27株为CK,仅3株菌鉴定失败,该结果与16SrRNA测序结果一致性较高,但是27份标本中鉴定为CK的质量分数相对较低。结论:MALDI-TOF-MS技术在棒状杆菌属细菌鉴定方面的应用可以为临床诊治GM方面提供病原学理论依据。

Detection of Sialylated N-Linked Glycans by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry

Native and methyl-esterified sialylated glycans were analyzed with 2,4,6-trihydroxyacetophenone（THAP）and 2,5-dihydroxybenzoic acid（DHB）as matrix by a matrix-assisted laser desorption/ionization time-of-flight mass spectrometer（MALDI-TOF MS）.High quality negative-ion spectra of commercial sialylated glycan were obtained with THAP as matrix.Detection limit of the glycan was less than 0.1 pmol.After methyl esterification of sialic acid（SA）residue,sialylated glycans were detected sensitively in the positive-ion mode using DHB as matrix.Neutral and sialylated glycans from the mixture of asialofetuin and fetuin were methylesterified and simultaneously recognized in one manipulation.Methyl esterification of SA residue offers a convenient and sensitive way to identify the structure of N-linked glycans for glycan profiling.

MALDI-TOF MS与VITEK2在血流感染致病菌快速鉴定及药敏试验中的应用

目的:探究基质辅助激光解吸/电离飞行时间质谱(Matrix-assisted laser desorption/ionizationtime-of-flight mass spectrometry,MALDI-TOF MS)与VITEK2在血流感染致病菌药敏试验中的联合应用效果。方法:选取景德镇市第二人民医院检验科2022年1月1日至2022年12月31日血流感染阳性样本126份,分别行常规鉴定及MALDI-TOF MS鉴定,完成菌株鉴定后通过VITEK2系统行抗菌药物敏感性试验(Antimicrobial susceptibility testing,AST),比较2种鉴定方法的细菌菌株鉴定结果及细菌耐药情况。结果:常规鉴定方法对革兰氏阴性、革兰氏阳性菌在属、种水平鉴定符合率达到100%;MALDI-TOF MS鉴定革兰氏阴性菌在属水平的符合率达97.7%(85/87),在种水平的符合率达95.4%(83/87),2例无结果(1例阴沟肠杆菌阴沟亚种,1例少动鞘氨醇单胞菌);MALDI-TOF MS鉴定革兰氏阳性菌在属、种水平的符合率均达97.4%(38/39),1例无结果(科氏葡萄球菌解脲亚种)。常规鉴定+VITEK2对革兰氏阴性菌AST分析的分类一致(Categorical agreement,CA)、基本一致(Essential agreement,EA)分别达到98.6%(1086/1101)、99.5%(1096/1101),对革兰氏阳性菌AST分析的CA、EA分别达到98.6%(550/558)、99.6%(556/558);MALDI-TOF MS+VITEK2(VITEK MS)对革兰氏阴性菌AST分析的CA、EA分别达到98.3%(1082/1101)、99.5%(1095/1101),对革兰氏阳性菌AST分析的CA、EA分别达到97.8%(546/558)、99.5%(555/558)。进一步参考肉汤稀释法药敏结果行一致性分析。结果发现,常规鉴定+VITEK2在革兰氏阴性菌的药敏试验中,10份AST鉴定结果出现小误差(Minus errors,MIE),5份AST鉴定结果出现重大误差(Major errors,ME);在革兰氏阳性菌的药敏试验中,8份AST鉴定结果出现MIE,2份AST鉴定结果出现ME。VITEK MS在革兰氏阳性菌的药敏试验中,13份AST鉴定结果出现MIE,6份AST鉴定结果出现ME;在革兰氏阳性菌的药敏试验中,9份AST鉴定结果出现MIE,3份AST鉴定结果出现ME。结论:MALDI-TOF MS联合VITEK2在临床血流感染致病菌鉴定及药敏试验中可快速、精确实现诊断并提供AST报告。

MALDI-TOF MS在血流感染快速鉴定病原菌中的应用

目的探讨基质辅助激光解吸电离飞行时间质谱(matrix-assisted laser desorption/ionization time of flight mass spectrometry,MALDI-TOF MS)结合短时培养在快速鉴定血流感染病原菌中的应用。方法对南京医科大学附属淮安第一医院微生物室2020年11月至2021年12月血培养报告阳性的标本进行革兰染色分类,并采用4h和6h短时培养法及MALDI-TOF MS技术快速鉴定感染病原菌并实时报送病区单元。结果4h短时培养革兰阴性菌共351株,339株(96.6%)细菌鉴定到种属,与24h鉴定结果相同,11株无鉴定结果,1株鉴定错误;6h短时培养革兰阳性菌共216株,212株(98.1%)鉴定到种属,与24h鉴定结果相同,3株无鉴定结果,1株鉴定错误。跟踪321株革兰阴性菌的临床反馈,287例(89.4%)给予临床关注,89例(27.7%)进行药物调整,238例(74.1%)临床疗效良好;跟踪183株革兰阳性菌的临床反馈,其中150例(82.0%)给予临床关注,49例(26.8%)进行药物调整,131例(71.6%)临床疗效良好。结论MALDI-TOF MS技术结合短时培养方法可有效提高血流感染病原菌鉴定准确率,改善血流感染患者抗菌药物治疗时机。

基于MALDI-TOF MS的血清多肽组学在胰腺良恶性疾病鉴别诊断中的应用

目的探讨基于基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)的血清多肽组学在胰腺良恶性疾病鉴别诊断中的价值。方法选取胰腺导管腺癌(PDAC)患者176例、慢性胰腺炎(CP)患者148例,按7∶3的比例随机分成训练集(PDAC 122例、CP 103例)和验证集(PDAC 54例、CP 45例)。采用弱阳性离子交换法结合磁珠吸附提取血清多肽,采用MALDI-TOF MS检测多肽谱。在训练集中采用二分类Logistic回归分析建立基于差异表达多肽的PDAC和CP的鉴别诊断模型,并在验证集中进行验证。采用纳米液相色谱-电喷雾串联质谱(nano-LC/ESI-MS/MS)测定差异表达多肽的氨基酸序列,并鉴定其所属的蛋白质。采用受试者工作特征(ROC)曲线评价鉴别诊断模型鉴别PDAC和CP的效能,并与血清糖类抗原19-9(CA19-9)的鉴别诊断效能进行比较。结果共发现20个PDAC患者与CP患者之间有显著差异的多肽,依此建立的鉴别诊断模型鉴别PDAC和CP的曲线下面积(AUC)为0.988,最佳临界值为0.469,敏感性为94.26%,特异性为97.09%。在验证集中,该模型的敏感性为94.44%,特异性为97.78%;鉴别诊断模型效能优于血清CA19-9(敏感性为67.90%,特异性为91.30%)。鉴别诊断模型与CA19-9联合,鉴别PDAC和CP的AUC为0.996,敏感性为97.60%,特异性为100.00%。采用nano-LC/ESI-MS/MS成功鉴定出3种多肽所属蛋白质,m/z 1758为斑联蛋白片段,m/z 4053和m/z 5351均为纤维蛋白原片段。结论基于血清多肽组学建立的PDAC和CP鉴别诊断模型能较准确地区分胰腺良恶性疾病,为建立非侵入性肿瘤诊断方法提供了新思路。

MALDI-TOF质谱技术对猪肠道菌群中携带mcr-1细菌的鉴定与聚类分型

为了解多粘菌素耐药基因mcr-1在猪肠道微生物群落中的分布特征,本研究采集分离同一猪肠道样品中的多粘菌素耐药菌,利用PCR进行mcr-1基因检测,采用基质辅助激光解析电离飞行时间质谱(MALDI-TOF MS)技术对mcr-1阳性菌株进行种属鉴定与亲缘关系分析。结果显示,在收集获得的325株多粘菌素耐药菌中,136株(41.8%)含有mcr-1基因,包括大肠杆菌70株,肺炎克雷伯菌19株,放线杆菌47株。细菌蛋白指纹图谱进行聚类分析显示,70株mcr-1阳性大肠杆菌被划分为13个亚型,19株肺炎克雷伯菌被分为3个亚型,其中有17株菌属于同一亚型(占89.5%),47株放线杆菌均为同一克隆。上述结果表明mcr-1在肠道菌群中存在克隆传播现象,细菌指纹图谱的多样性也提示可能存在质粒或者其他转移元件介导的mcr-1水平传播。MALDI-TOF-MS作为一种新的技术,不仅能够实现细菌的快速鉴定,而且可基于细菌蛋白指纹图谱对菌株进行初步的亲缘关系分析。

基于MALDI-MS的组织上脂肪酸原位衍生化综合实验教学设计

针对MALDI-MS在低丰度脂肪酸分析时的难点,将分析化学中的原位衍生化技术应用到脂肪酸MALDI-MS分析中,对小鼠心肌组织、脑组织和甲状腺肿瘤组织中低丰度的脂肪酸进行了原位衍生化,并对衍生化产物采用高分辨质谱和串联质谱技术进行了分析验证。该实验不仅能够使学生熟练掌握大型质谱仪器的实验原理和操作方法,还能够培养学生从生物样本获得、样本前处理到组织上原位衍生化及高分辨质谱数据分析与处理等多方面能力。

MALDI-TOF MS在不同禽肉动物源性成分检测中的研究

[目的]建立基质辅助激光解吸电离飞行时间质谱(matrix-assisted laser desorption ionization-time of flight mass spectrometry, MALDI-TOF MS)技术检测不同禽肉动物源性成分的方法,构建不同禽肉蛋白质分子指纹图谱标准数据库,对不同禽肉进行鉴别。[方法]样品用磷酸盐缓冲液提取,净化后用MALDI-TOF MS法测定。采用ChemPattern软件对不同禽肉蛋白图谱进行化学计量学分析,建立识别模型。[结果]鸡、鸭、鹅3种不同禽肉之间具有明显差异。首次建立不同禽肉蛋白质分子指纹图谱标准数据库,可一次性对每个样品中鸡、鸭、鹅等肉源性成分进行同时分析。[结论]建立的基于蛋白质组学的鸡、鸭、鹅源性成分鉴定系统具有简便、稳定、准确、重现性好的优点,适用于不同禽肉中鸡鸭鹅动物源性成分的鉴别。