Immunomagnetic beads enrichment kit for detection of aflatoxin B1(AFB1) was prepared through reaction of AFB1 and p-phenylenediamine. The catches of AFB1 by the kit were 25 ng/mg. Furthermore, AFB1 was conducted speci...Immunomagnetic beads enrichment kit for detection of aflatoxin B1(AFB1) was prepared through reaction of AFB1 and p-phenylenediamine. The catches of AFB1 by the kit were 25 ng/mg. Furthermore, AFB1 was conducted specific reaction with competitive drugs with similar structure or function to AFB1, including aflatoxin M1, T-2 toxin, ochratoxin A, zearalenone and patulin, and no cross reaction was observed.展开更多
An immunomagnetic bead kit to separate and enrich salbutamol was prepared through the reaction between salbutamol and 4-aminobenzoic acid.The kit had a catch of 20 ng/ml to salbutamol in samples,and showed no cross re...An immunomagnetic bead kit to separate and enrich salbutamol was prepared through the reaction between salbutamol and 4-aminobenzoic acid.The kit had a catch of 20 ng/ml to salbutamol in samples,and showed no cross reaction with competitive drugs with structure and function similar to salbutamol: clenbuterol,ractopamine,phenylethanolamine A, bromchlorbuterol, brombuterol, terbutaline, hydroxymethyl salbutamol,cimaterol,tulobuterol,mapenterol,cimbuterol,clenpenterol,zilpaterol,penbutolol,clenproperol,mabuterol and clorprenaline.展开更多
基于纳米抗体(nanobody,Nb)和磁小体(bacterial magnetic particles,BMPs)的免疫磁珠在污染物分离分析中具有良好的应用前景,然而,不同长度柔性连接肽(linker)对免疫磁珠性能的影响尚未见相关报道。为了探究柔性连接肽长度对免疫磁珠的...基于纳米抗体(nanobody,Nb)和磁小体(bacterial magnetic particles,BMPs)的免疫磁珠在污染物分离分析中具有良好的应用前景,然而,不同长度柔性连接肽(linker)对免疫磁珠性能的影响尚未见相关报道。为了探究柔性连接肽长度对免疫磁珠的性能影响,本研究使用pET-28a作为载体,在磺胺间二甲氧嘧啶(sulfadimethoxine,SDM)Nb基因上融合了不同长度的柔性连接肽,分别为pET28a-SDM-Nb-(G4S)1-Cys和pET28a-SDM-Nb-(G4S)4-Cys,并使用大肠杆菌BL21(DE3)作为重组工程菌进行表达,最终获得Nb-(G4S)1-Cys和Nb-(G4S)4-Cys重组蛋白质。利用异源双功能试剂3-(2-吡啶二巯基)丙酸N-羟基琥珀酰亚胺酯(N-succinimidyl-3-(2-pyridyldithiol)propionate,SPDP),分别将重组蛋白质与BMPs进行偶联,构建了免疫磁珠。利用免疫印迹对偶联结果进行了初步鉴定,并对偶联条件进行了优化。同时,使用透射电镜和Zeta电位分析仪对免疫磁珠的水合粒径、Zeta电位和分散性进行了分析。研究结果表明,SPDP能有效地将Nb-(G4S)1-Cys和Nb-(G4S)4-Cys定向固定在BMPs表面。通过差值法计算发现,Nb-(G4S)1-Cys与BMPs的偶联效率高于Nb-(G4S)4-Cys与BMPs的偶联效率。进一步表征结果显示,BMP-(G4S)1-Nb的Zeta电位绝对值更高,水合粒径更小,并且具有较低的多分散性指数,说明其在水相体系中具有更强的胶体稳定性。综上所述,利用BMPs和Nb-(G4S)1-Cys构建的免疫磁珠性能优于BMPs和Nb-(G4S)4-Cys构建的免疫磁珠。这为今后选择合适长度的连接肽构建高效的免疫磁珠分离分析SDM提供了理论依据。展开更多
This study describes a detailed process for obtaining brain glioma stem cells from freshly dissected human brain glioma samples using an immunomagnetic bead technique combined with serum-free media pressure screening....This study describes a detailed process for obtaining brain glioma stem cells from freshly dissected human brain glioma samples using an immunomagnetic bead technique combined with serum-free media pressure screening. Furthermore, the proliferation, differentiation and self-renewal biological features of brain glioma stem cells were identified. Results showed that a small number of CD133 positive tumor cells isolated from brain glioma samples survived as a cell suspension in serum-free media and proliferated. Subcultured CD133 positive cells maintained a potent self-renewal and proliferative ability, and expressed the stem cell-specific markers CD133 and nestin. After incubation with fetal bovine serum, the number of glial fibrillary acidic protein and microtubule associated protein 2 positive cells increased significantly, indicating that the cultured brain glioma stem cells can differentiate into astrocytes and neurons. Western blot analysis showed that tumor suppressor phosphatase and tensin homolog was highly expressed in tumor spheres compared with the differentiated tumor cells. These experimental findings indicate that the immunomagnetic beads technique is a useful method to obtain brain glioma stem cells from human brain tumors.展开更多
Immunomagnetic bead(IMB)-based detection has great potential for biomedical applications.Passive and active strategies,including microfluidics and magnetic actuation methods,have been developed to mix IMBs and analyte...Immunomagnetic bead(IMB)-based detection has great potential for biomedical applications.Passive and active strategies,including microfluidics and magnetic actuation methods,have been developed to mix IMBs and analytes efficiently.However,cost-effective on-site detection using a simple microfluidic chip is challenging,and miniaturization of the magnetic driving device is imperative for portability.In this study,we propose a novel mixing method for an on-chip IMB swarm via magnetic actuation and mechanical vibration.A microfluidic chip system coupled with double spiral magnetic coils and a vibration motor was fabricated.The aggregation behavior of IMBs under magnetic fields and the diffusion behavior of the IMB swarm under mechanical vibration were analyzed in detail.Based on the synergetic effects of magnetic actuation and mechanical vibration,we achieved the highly efficient capturing of Vibrio parahaemolyticus DNA and goat anti-human immunoglobulin G by mixing the IMB swarm with the microfluidic chip.In this case,the antigen detection rate could reach~94.4%.Given its fascinating features,such IMB-microfluidic detection demonstrates significant potential for biomedical applications.展开更多
基金Supported by Hundred Leading Talents Training Project of Science and Technology Beijing(Z171100001117158)
文摘Immunomagnetic beads enrichment kit for detection of aflatoxin B1(AFB1) was prepared through reaction of AFB1 and p-phenylenediamine. The catches of AFB1 by the kit were 25 ng/mg. Furthermore, AFB1 was conducted specific reaction with competitive drugs with similar structure or function to AFB1, including aflatoxin M1, T-2 toxin, ochratoxin A, zearalenone and patulin, and no cross reaction was observed.
基金Supported by Beijing Training Project for the Leading Talents in S&T(Z171100001117158)
文摘An immunomagnetic bead kit to separate and enrich salbutamol was prepared through the reaction between salbutamol and 4-aminobenzoic acid.The kit had a catch of 20 ng/ml to salbutamol in samples,and showed no cross reaction with competitive drugs with structure and function similar to salbutamol: clenbuterol,ractopamine,phenylethanolamine A, bromchlorbuterol, brombuterol, terbutaline, hydroxymethyl salbutamol,cimaterol,tulobuterol,mapenterol,cimbuterol,clenpenterol,zilpaterol,penbutolol,clenproperol,mabuterol and clorprenaline.
文摘基于纳米抗体(nanobody,Nb)和磁小体(bacterial magnetic particles,BMPs)的免疫磁珠在污染物分离分析中具有良好的应用前景,然而,不同长度柔性连接肽(linker)对免疫磁珠性能的影响尚未见相关报道。为了探究柔性连接肽长度对免疫磁珠的性能影响,本研究使用pET-28a作为载体,在磺胺间二甲氧嘧啶(sulfadimethoxine,SDM)Nb基因上融合了不同长度的柔性连接肽,分别为pET28a-SDM-Nb-(G4S)1-Cys和pET28a-SDM-Nb-(G4S)4-Cys,并使用大肠杆菌BL21(DE3)作为重组工程菌进行表达,最终获得Nb-(G4S)1-Cys和Nb-(G4S)4-Cys重组蛋白质。利用异源双功能试剂3-(2-吡啶二巯基)丙酸N-羟基琥珀酰亚胺酯(N-succinimidyl-3-(2-pyridyldithiol)propionate,SPDP),分别将重组蛋白质与BMPs进行偶联,构建了免疫磁珠。利用免疫印迹对偶联结果进行了初步鉴定,并对偶联条件进行了优化。同时,使用透射电镜和Zeta电位分析仪对免疫磁珠的水合粒径、Zeta电位和分散性进行了分析。研究结果表明,SPDP能有效地将Nb-(G4S)1-Cys和Nb-(G4S)4-Cys定向固定在BMPs表面。通过差值法计算发现,Nb-(G4S)1-Cys与BMPs的偶联效率高于Nb-(G4S)4-Cys与BMPs的偶联效率。进一步表征结果显示,BMP-(G4S)1-Nb的Zeta电位绝对值更高,水合粒径更小,并且具有较低的多分散性指数,说明其在水相体系中具有更强的胶体稳定性。综上所述,利用BMPs和Nb-(G4S)1-Cys构建的免疫磁珠性能优于BMPs和Nb-(G4S)4-Cys构建的免疫磁珠。这为今后选择合适长度的连接肽构建高效的免疫磁珠分离分析SDM提供了理论依据。
基金supported in part by the National Natural Science Foundation of China,No.81072072,31070933the guidance project of Xuzhou Science and Technology Bureau,No.X22D1056
文摘This study describes a detailed process for obtaining brain glioma stem cells from freshly dissected human brain glioma samples using an immunomagnetic bead technique combined with serum-free media pressure screening. Furthermore, the proliferation, differentiation and self-renewal biological features of brain glioma stem cells were identified. Results showed that a small number of CD133 positive tumor cells isolated from brain glioma samples survived as a cell suspension in serum-free media and proliferated. Subcultured CD133 positive cells maintained a potent self-renewal and proliferative ability, and expressed the stem cell-specific markers CD133 and nestin. After incubation with fetal bovine serum, the number of glial fibrillary acidic protein and microtubule associated protein 2 positive cells increased significantly, indicating that the cultured brain glioma stem cells can differentiate into astrocytes and neurons. Western blot analysis showed that tumor suppressor phosphatase and tensin homolog was highly expressed in tumor spheres compared with the differentiated tumor cells. These experimental findings indicate that the immunomagnetic beads technique is a useful method to obtain brain glioma stem cells from human brain tumors.
基金supported by the National Natural Science Foundation of China(Grant No.51975574)the Fundamental Research Funds for the Central Universities(Grant No.2020TC017)。
文摘Immunomagnetic bead(IMB)-based detection has great potential for biomedical applications.Passive and active strategies,including microfluidics and magnetic actuation methods,have been developed to mix IMBs and analytes efficiently.However,cost-effective on-site detection using a simple microfluidic chip is challenging,and miniaturization of the magnetic driving device is imperative for portability.In this study,we propose a novel mixing method for an on-chip IMB swarm via magnetic actuation and mechanical vibration.A microfluidic chip system coupled with double spiral magnetic coils and a vibration motor was fabricated.The aggregation behavior of IMBs under magnetic fields and the diffusion behavior of the IMB swarm under mechanical vibration were analyzed in detail.Based on the synergetic effects of magnetic actuation and mechanical vibration,we achieved the highly efficient capturing of Vibrio parahaemolyticus DNA and goat anti-human immunoglobulin G by mixing the IMB swarm with the microfluidic chip.In this case,the antigen detection rate could reach~94.4%.Given its fascinating features,such IMB-microfluidic detection demonstrates significant potential for biomedical applications.
