热敏型脂质体介导的免疫电化学超灵敏检测癌胚抗原
本文是Anal Chem上的ASAP文章，介绍的是采用脂质体包裹的HRP进行免疫电化学方面的研究工作，其工作的主要特色在于采用五种不同的方式把抗体分子交联到脂质体表面，并对五种不同的交联方式进行考虑对比研究，对于同种类型的实验参考意义很大。
Signal-Enhancing Thermosensitive Liposomes for Highly Sensitive Immunosensor Development
Rükan Genc , Deirdre Murphy, Alex Fragoso,Mayreli Ortiz,*, and Ciara K. O’Sullivan*
Nanobiotechnology and Bioanalysis Group, Departament d’Enginyer??a Qu??mica, Universitat Rovira i Virgili, Avinguda
Pa sos Catalans, 26, 43007 Tarragona, Spain, Institucio? Catalana de Recerca i Estudis Avanc ats, Passeig Lluis
Companys 23, 08010, Barcelona, Spain
Liposomes are potential candidates as nanovesicles for the development of detection systems with improved sensitivity and detection limits, due to their capacity to encapsulate diverse types of signal enhancing molecules. An amperometric immunosensor exploiting enzyme encapsulating
thermosensitive liposomes for the ultrasensitive detection of carcinoembryonic antigen (CEA) is reported. Five different bioconjugation methods to link an anti-CEA antibody to horseradish peroxidase (HRP) encapsulating liposomes were studied and compared to HRP-Ab conjugate. -Potential measurements of liposomes before and after each modification method as well as following incubation with CEA were used as a tool to
monitor the success of modification and probe the affinity of the liposome linked antibodies. The use of different lysing conditions (temperature vs detergent) was evaluated, with the application of temperature providing an extremely effective means of liposome lysis. Finally, thermosensitive liposomes modified using biotinstreptavidin and N-succinimidyl-S-acetylthioacetate (SATA)/ sulfosuccinimidyl 4-(N-maleimidomethyl) cyclohexane-1- 1-carboxylate (Sulfo-SMCC) chemistries were used to detect CEA and compared in terms of their stability, background signal, and limit of detection. Detection limits of 2 orders of magnitude lower than that obtained with the HRP-antibody reporter conjugate were obtained
(0.080 ng CEA/mL and 0.0113 ng CEA/mL), with 11- fold and 9-fold amplification of signal, for the biotinstreptavidin and SATA/Sulfo-SMCC modified liposomes respectively, clearly demonstrating the powerful potential of enzyme encapsulating liposomes as signal enhancement tools.
