Validation of an immunoassay for fast screening of bisphenol A in canned vegetables

The effects of BPA exposure on human health are an issue of concern and controversy. In the present work, the validation for the first time of a monoclonal antibody-based enzyme-linked immunoassay (ELISA) for BPA determination in canned vegetables is described, using HPLC as the reference method. From a collection of monoclonal antibodies, a high-sensitivity immunoassay was selected on the basis of its tolerance to organic solvents and the influence of matrix effects. This ELISA displayed a limit of detection of 3 µg kg−1of BPA in whole product of canned vegetables and 15 µg L−1 of BPA in the liquid portion. For assay validation, processed vegetables were fortified with BPA at 10, 50, and 200 µg kg−1. Sample treatment rendered crude and purified extracts. Purified extracts were analyzed by HPLC and ELISA, while crude extracts could be analyzed only by ELISA. Depending on the crop and the fortification level, good recoveries were obtained for both methods: 70.6-105 % for HPLC and 61.4-115 % (purified extracts) or 82-120 % (crude extracts) for ELISA. HPLC was more precise than ELISA. Finally, crude extracts of canned peas were analyzed by ELISA. Results (33−62 µg kg−1) also compared well with those obtained by HPLC on purified extracts (23−44 µg kg−1). In all samples, BPA concentration was significantly lower than the specific migration level of 600 µg kg−1 established by the European Commission. Therefore, the ELISA herein validated constitutes a sensitive, fast, and high-throughput technique for BPA screening in canned vegetables.The authors thank the Spanish Ministerio de Ciencia y Tecnologia for financial support (project AGL2006-13361) and Dr Miguel Gamon and David Romera for performing the HPLC analysis.Manclus Ciscar, JJ.; Moreno Tamarit, MJ.; Montoya Baides, Á. (2013). Validation of an immunoassay for fast screening of bisphenol A in canned vegetables. Analytical Methods. 5(16):4244-4251. https://doi.org/10.1039/c3ay40855hS42444251516Vandenberg, L. N., Hauser, R., Marcus, M., Olea, N., & Welshons, W. V. (2007). Human exposure to bisphenol A (BPA). Reproductive Toxicology, 24(2), 139-177. doi:10.1016/j.reprotox.2007.07.010Vom Saal, F. S., Akingbemi, B. T., Belcher, S. M., Birnbaum, L. S., Crain, D. A., Eriksen, M., … Zoeller, R. T. (2007). Chapel Hill bisphenol A expert panel consensus statement: Integration of mechanisms, effects in animals and potential to impact human health at current levels of exposure. Reproductive Toxicology, 24(2), 131-138. doi:10.1016/j.reprotox.2007.07.005Vandenberg, L. N., Chahoud, I., Heindel, J. J., Padmanabhan, V., Paumgartten, F. J. R., & Schoenfelder, G. (2010). Urinary, Circulating, and Tissue Biomonitoring Studies Indicate Widespread Exposure to Bisphenol A. Environmental Health Perspectives, 118(8), 1055-1070. doi:10.1289/ehp.0901716Vandenberg, L. N., Maffini, M. V., Sonnenschein, C., Rubin, B. S., & Soto, A. M. (2009). Bisphenol-A and the Great Divide: A Review of Controversies in the Field of Endocrine Disruption. Endocrine Reviews, 30(1), 75-95. doi:10.1210/er.2008-0021CAO, X.-L., CORRIVEAU, J., & POPOVIC, S. (2010). Bisphenol A in Canned Food Products from Canadian Markets. Journal of Food Protection, 73(6), 1085-1089. doi:10.4315/0362-028x-73.6.1085Schecter, A., Malik, N., Haffner, D., Smith, S., Harris, T. R., Paepke, O., & Birnbaum, L. (2010). Bisphenol A (BPA) in U.S. Food. Environmental Science & Technology, 44(24), 9425-9430. doi:10.1021/es102785dGarcía-Prieto, A., Lunar, L., Rubio, S., & Pérez-Bendito, D. (2008). Decanoic acid reverse micelle-based coacervates for the microextraction of bisphenol A from canned vegetables and fruits. Analytica Chimica Acta, 617(1-2), 51-58. doi:10.1016/j.aca.2008.01.061Ballesteros-Gómez, A., Rubio, S., & Pérez-Bendito, D. (2009). Analytical methods for the determination of bisphenol A in food. Journal of Chromatography A, 1216(3), 449-469. doi:10.1016/j.chroma.2008.06.037Yoshida, T., Horie, M., Hoshino, Y., Nakazawa, H., Horie, M., & Nakazawa, H. (2001). Determination of bisphenol A in canned vegetables and fruit by high performance liquid chromatography. Food Additives and Contaminants, 18(1), 69-75. doi:10.1080/026520301446412Brotons, J. A., Olea-Serrano, M. F., Villalobos, M., Pedraza, V., & Olea, N. (1995). Xenoestrogens released from lacquer coatings in food cans. Environmental Health Perspectives, 103(6), 608-612. doi:10.1289/ehp.95103608KODAIRA, T., KATO, I., LI, J., MOCHIZUKI, T., HOSHINO, M., USAKI, Y., … YANAIHARA, N. (2000). Novel ELISA for the Measurement of Immunoreactive Bisphenol A. Biomedical Research, 21(2), 117-121. doi:10.2220/biomedres.21.117Ohkuma, H., Abe, K., Ito, M., Kokado, A., Kambegawa, A., & Maeda, M. (2001). Development of a highly sensitive enzyme-linked immunosorbent assay for bisphenol A in serum. The Analyst, 127(1), 93-97. doi:10.1039/b103515kDe Meulenaer, B., Baert, K., Lanckriet, H., Van Hoed, V., & Huyghebaert, A. (2002). Development of an Enzyme-Linked Immunosorbent Assay for Bisphenol A Using Chicken Immunoglobulins. Journal of Agricultural and Food Chemistry, 50(19), 5273-5282. doi:10.1021/jf0202739Marchesini, G. R., Meulenberg, E., Haasnoot, W., & Irth, H. (2005). Biosensor immunoassays for the detection of bisphenol A. Analytica Chimica Acta, 528(1), 37-45. doi:10.1016/j.aca.2004.06.066Rahman, M. A., Shiddiky, M. J. A., Park, J.-S., & Shim, Y.-B. (2007). An impedimetric immunosensor for the label-free detection of bisphenol A. Biosensors and Bioelectronics, 22(11), 2464-2470. doi:10.1016/j.bios.2006.09.010Li, L., Wang, J., Zhou, S., & Zhao, M. (2008). Development and characterization of an immunoaffinity monolith for selective on-line extraction of bisphenol A from environmental water samples. Analytica Chimica Acta, 620(1-2), 1-7. doi:10.1016/j.aca.2008.05.036NISHII, S., SOYA, Y., MATSUI, K., ISHIBASHI, T., & KAWAMURA, Y. (2000). Down-Sizing in Analytical Chemistry. Determination of bisphenol A by ELISA using an organic solvent-resistant anti-bisphenol A monoclonal antibody. BUNSEKI KAGAKU, 49(12), 969-975. doi:10.2116/bunsekikagaku.49.969NISHI, K., TAKAI, M., MORIMUNE, K., & OHKAWA, H. (2003). Molecular and Immunochemical Characteristics of Monoclonal and Recombinant Antibodies Specific to Bisphenol A. Bioscience, Biotechnology, and Biochemistry, 67(6), 1358-1367. doi:10.1271/bbb.67.1358Ju, C., Xiong, Y., Gao, A., Yang, T., & Wang, L. (2011). Development of a Direct Competitive Enzyme-linked Immunosorbent Assay Using a Sensitive Monoclonal Antibody for Bisphenol A. Hybridoma, 30(1), 95-100. doi:10.1089/hyb.2010.0079Feng, Y., Ning, B., Su, P., Wang, H., Wang, C., Chen, F., & Gao, Z. (2009). An immunoassay for bisphenol A based on direct hapten conjugation to the polystyrene surface of microtiter plates. Talanta, 80(2), 803-808. doi:10.1016/j.talanta.2009.07.070Braunrath, R., Podlipna, D., Padlesak, S., & Cichna-Markl, M. (2005). Determination of Bisphenol A in Canned Foods by Immunoaffinity Chromatography, HPLC, and Fluorescence Detection. Journal of Agricultural and Food Chemistry, 53(23), 8911-8917. doi:10.1021/jf051525jInui, H., Takehara, A., Doi, F., Nishi, K., Takai, M., Miyake, S., & Ohkawa, H. (2009). A scFv Antibody-Based Immunoaffinity Chromatography Column for Clean-Up of Bisphenol A-Contaminated Water Samples. Journal of Agricultural and Food Chemistry, 57(2), 353-358. doi:10.1021/jf802781tLu, Y., Peterson, J. R., Gooding, J. J., & Lee, N. A. (2012). Development of sensitive direct and indirect enzyme-linked immunosorbent assays (ELISAs) for monitoring bisphenol-A in canned foods and beverages. Analytical and Bioanalytical Chemistry, 403(6), 1607-1618. doi:10.1007/s00216-012-5969-8Negre, M., Monterumici, C. M., Vindrola, D., & Piccone, G. (2011). Changes in chemical and biological parameters during co-composting of anaerobically digested sewage sludges with lignocellulosic material. Journal of Environmental Science and Health, Part A, 46(5), 509-517. doi:10.1080/10934529.2011.551737Manclus, J. J., Primo, J., & Montoya, A. (1994). Development of a Chlorpyrifos Immunoassay Using Antibodies Obtained from a Simple Hapten Design. Journal of Agricultural and Food Chemistry, 42(6), 1257-1260. doi:10.1021/jf00042a00

Bisphenol A determination in baby bottles by chemiluminescent enzyme-linked immunosorbent assay, lateral flow immunoassay and liquid chromatography tandem mass spectrometry

Two immunoassays, a Lateral Flow ImmunoAssay (LFIA) based on colloidal gold nanoparticle labels and an indirect competitive chemiluminescence enzyme-linked immunosorbent assay (CL-ELISA), were developed and a high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was optimized to assess the possible release of bisphenol A (BPA, 4,4¿-isopropylidenediphenol) from different plastic baby bottles treated with simulating solutions. Coating conjugate concentration, anti-BPA antibody dilution, incubation time of the primary and secondary antibodies, and tolerance to different organic solvents were optimized to obtain the best performance of the ELISA with chemiluminescent end-point detection. The influence of different buffers on LFIA performance was also evaluated. Both methods showed good repeatability (mean CV value around 13%) and sensitivity. Reproducibility tests for CL-ELISA gave a mean CV value of about 25%. The IC50 and Limit of Detection (LOD) values of CL-ELISA were 0.2 and 0.02 ng mL¿1, respectively. The LOD of LFIA was 0.1 ¿g mL¿1. A LC-MS/MS method was also optimized. The separation was performed in a C18 column with a triple-quadrupole mass spectrometer with electrospray ionisation interface. The method showed a good linearity in the range 2 to 500 ng mL¿1, with a regression coefficient of 0.998. In the simulating solutions the detection and quantification limits, calculated by the signal to noise level of 3 (S/N = 3), were 5.8 ng mL¿1 and 17.4 ng mL¿1, respectively. This limit of quantification was about 3 and 35 times lower than the permitted limits set by the official method CEN/TS 13130-13 (0.05 ¿g mL¿1) and by the Directive 2004/19/EC (0.6 ¿g mL¿1), respectively. The methods were applied to determine BPA release from baby bottles, performing repeated procedures according to EU and national regulations. The results demonstrated that no BPA migration from the tested plastic materials occurred with only one exception. The migrated amount, above the regulatory limits, was detected by all the mentioned assaysThis work was supported by a grant from the University of Bologna (RFO-Focused Fundamental Research Projects 2000-2011) grants.Maiolini, E.; Ferri, E.; Pitasi, AL.; Montoya Baides, Á.; Di Giovanni, M.; Errani, E.; Girotti, S. (2014). Bisphenol A determination in baby bottles by chemiluminescent enzyme-linked immunosorbent assay, lateral flow immunoassay and liquid chromatography tandem mass spectrometry. Analyst. 139(1):318-324. doi:10.1039/c3an00552fS3183241391The Bisphenol-A, http://www.bisphenol-a.org, accessed 04 July 2013Diamanti-Kandarakis, E., Bourguignon, J.-P., Giudice, L. C., Hauser, R., Prins, G. S., Soto, A. M., … Gore, A. C. (2009). Endocrine-Disrupting Chemicals: An Endocrine Society Scientific Statement. Endocrine Reviews, 30(4), 293-342. doi:10.1210/er.2009-0002Ward, J. L., & Blum, M. J. (2012). Exposure to an environmental estrogen breaks down sexual isolation between native and invasive species. Evolutionary Applications, 5(8), 901-912. doi:10.1111/j.1752-4571.2012.00283.xNagel, S. C., Vom Saal, F. S., & Welshons, W. V. (1998). The Effective Free Fraction of Estradiol and Xenoestrogens in Human Serum Measured by Whole Cell Uptake Assays: Physiology of Delivery Modifies Estrogenic Activity. Experimental Biology and Medicine, 217(3), 300-309. doi:10.3181/00379727-217-44236MacLusky, N., & Naftolin, F. (1981). Sexual differentiation of the central nervous system. Science, 211(4488), 1294-1302. doi:10.1126/science.6163211Cabaton, N. J., Wadia, P. R., Rubin, B. S., Zalko, D., Schaeberle, C. M., Askenase, M. H., … Soto, A. M. (2011). Perinatal Exposure to Environmentally Relevant Levels of Bisphenol A Decreases Fertility and Fecundity in CD-1 Mice. Environmental Health Perspectives, 119(4), 547-552. doi:10.1289/ehp.1002559Muñoz-de-Toro, M., Markey, C. M., Wadia, P. R., Luque, E. H., Rubin, B. S., Sonnenschein, C., & Soto, A. M. (2005). Perinatal Exposure to Bisphenol-A Alters Peripubertal Mammary Gland Development in Mice. Endocrinology, 146(9), 4138-4147. doi:10.1210/en.2005-0340Regulation of the European Commission (EU) No. 2011/10/EU of 14 January 2011 relating to materials and articles made of plastic material intended to come into contact with foodstuffs, http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2011:012:0001:0089:EN:PDF, accessed 04 July 2013Canada Gazette Part II 144(21): 1806–18, 13 October 2010, http://www.gazette.gc.ca/rp-pr/p2/2010/2010-10-13/pdf/g2-14421.pdf, accessed 04 July 2013Commission Directive 2011/8/EU of 28 January 2011 amending Directive 2002/72/EC, Off. J. Eur. Communities: Legis., 2011, 026, 1114F. Baldi and A.Mantovani, Baby bottle: Struggling for safety, Food and Veterinary Toxicology Unit – ISS, http://www.iss.it/prvn/focu/cont.php?id=281&lang=2&tipo=42, accessed 04 July 2013K. Aschberger , P.Castello, E.Hoekstra, S.Karakitsios, S.Munn, S.Pakalin and D.Sarigiannis, European Commission Joint Research Centre Institute for Health and Consumer Protection, http://publications.jrc.ec.europa.eu/repository/bitstream/111111111/14221/1/eur%2024389_bpa%20%20baby%20bottles_chall%20%20persp%20%282%29.pdf, accessed 04 July 2013Ballesteros-Gómez, A., Rubio, S., & Pérez-Bendito, D. (2009). Analytical methods for the determination of bisphenol A in food. Journal of Chromatography A, 1216(3), 449-469. doi:10.1016/j.chroma.2008.06.037Feng, Y., Ning, B., Su, P., Wang, H., Wang, C., Chen, F., & Gao, Z. (2009). An immunoassay for bisphenol A based on direct hapten conjugation to the polystyrene surface of microtiter plates. Talanta, 80(2), 803-808. doi:10.1016/j.talanta.2009.07.070Mudiam, M. K. R., Jain, R., Dua, V. K., Singh, A. K., Sharma, V. P., & Murthy, R. C. (2011). Application of ethyl chloroformate derivatization for solid-phase microextraction–gas chromatography–mass spectrometric determination of bisphenol-A in water and milk samples. Analytical and Bioanalytical Chemistry, 401(5), 1695-1701. doi:10.1007/s00216-011-5226-6Negre, M., Monterumici, C. M., Vindrola, D., & Piccone, G. (2011). Changes in chemical and biological parameters during co-composting of anaerobically digested sewage sludges with lignocellulosic material. Journal of Environmental Science and Health, Part A, 46(5), 509-517. doi:10.1080/10934529.2011.551737Noonan, G. O., Ackerman, L. K., & Begley, T. H. (2011). Concentration of Bisphenol A in Highly Consumed Canned Foods on the U.S. Market. Journal of Agricultural and Food Chemistry, 59(13), 7178-7185. doi:10.1021/jf201076fSchecter, A., Malik, N., Haffner, D., Smith, S., Harris, T. R., Paepke, O., & Birnbaum, L. (2010). Bisphenol A (BPA) in U.S. Food. Environmental Science & Technology, 44(24), 9425-9430. doi:10.1021/es102785dViganò, L., Benfenati, E., Cauwenberge, A. van, Eidem, J. K., Erratico, C., Goksøyr, A., … Urbatzka, R. (2008). Estrogenicity profile and estrogenic compounds determined in river sediments by chemical analysis, ELISA and yeast assays. Chemosphere, 73(7), 1078-1089. doi:10.1016/j.chemosphere.2008.07.057Fukata, H., Miyagawa, H., Yamazaki, N., & Mori, C. (2006). Comparison of Elisa- and LC-MS-Based Methodologies for the Exposure Assessment of Bisphenol A. Toxicology Mechanisms and Methods, 16(8), 427-430. doi:10.1080/15376520600697404Rezaee, M., Yamini, Y., Shariati, S., Esrafili, A., & Shamsipur, M. (2009). Dispersive liquid–liquid microextraction combined with high-performance liquid chromatography-UV detection as a very simple, rapid and sensitive method for the determination of bisphenol A in water samples. Journal of Chromatography A, 1216(9), 1511-1514. doi:10.1016/j.chroma.2008.12.091Liu, X., Ji, Y., Zhang, H., & Liu, M. (2008). Elimination of matrix effects in the determination of bisphenol A in milk by solid-phase microextraction–high-performance liquid chromatography. Food Additives & Contaminants: Part A, 25(6), 772-778. doi:10.1080/02652030701713921Farré, M., Kantiani, L., & Barceló, D. (2007). Advances in immunochemical technologies for analysis of organic pollutants in the environment. TrAC Trends in Analytical Chemistry, 26(11), 1100-1112. doi:10.1016/j.trac.2007.10.004Manclús, J. J., Moreno, M. J., & Montoya, Á. (2013). Validation of an immunoassay for fast screening of bisphenol A in canned vegetables. Analytical Methods, 5(16), 4244. doi:10.1039/c3ay40855hR. L. Gibson , Toxic Baby bottles: Scientific study finds leaching chemicals in clear plastic baby bottles, Environmental California Research & Policy Center, 2007, http://www.drldiego.com/docs/publications/Toxic_Baby_Bottles_sm.pdf, accessed 04 July 2013Commission Directive 93/8/EEC of 15 March 1993, Off. J. Eur. Communities: Legis., 1993, 90, 2225Directive 97/48/EC of 27 July 1997, Off. J. Eur. Communities: Legis., 1997, 222, 1013Decreto Ministeriale 21/03/1973, Gazzetta Ufficiale, Supplemento Ordinario 104, 20/04/1973Girotti, S., Maiolini, E., Ghini, S., Ferri, E., Fini, F., Nodet, P., & Eremin, S. (2008). Quantification of Thiram in Honeybees: Development of a Chemiluminescent ELISA. Analytical Letters, 41(1), 46-55. doi:10.1080/00032710701748291Botchkareva, A. E., Eremin, S. A., Montoya, A., Manclús, J. J., Mickova, B., Rauch, P., … Girotti, S. (2003). Development of chemiluminescent ELISAs to DDT and its metabolites in food and environmental samples. Journal of Immunological Methods, 283(1-2), 45-57. doi:10.1016/j.jim.2003.08.016FRENS, G. (1973). Controlled Nucleation for the Regulation of the Particle Size in Monodisperse Gold Suspensions. Nature Physical Science, 241(105), 20-22. doi:10.1038/physci241020a0Girotti, S., Eremin, S., Montoya, A., Moreno, M. J., Caputo, P., D’Elia, M., … Maiolini, E. (2009). Development of a chemiluminescent ELISA and a colloidal gold-based LFIA for TNT detection. Analytical and Bioanalytical Chemistry, 396(2), 687-695. doi:10.1007/s00216-009-3264-0Santillana, M. I., Ruiz, E., Nieto, M. T., Bustos, J., Maia, J., Sendón, R., & Sánchez, J. J. (2011). Migration of bisphenol A from polycarbonate baby bottles purchased in the Spanish market by liquid chromatography and fluorescence detection. 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Oscillator for Biosensors based on Quartz Crystal Microbalance (QCM)

[EN] Quartz crystal is generally used in some applications as a microbalance taking advantage of its capacity to change the resonance frequency according to any surface mass change on the resonator.In this way a quartz crystal can be used as a transducer in a piezoelectric inmunosensor system in order to detect antigen-antibody bonds. An interface for Quartz Crystal Microbalances, QCM, based on an improved version of an oscillator in balanced differential configuration and its respective validation as a biosensor characterization system is introduced in this paper. The system was successfully tested in a piezoelectric inmunosensor for detecting the pesticide Carbaryl.[ES] El cristal de cuarzo generalmente es usado en aplicaciones como microbalanza, aprovechando la capacidad que presenta éste para variar su frecuencia de resonancia de acuerdo a los cambios de la densidad superficial de masa depositada en la superficie del resonador. De esta manera, un cristal de cuarzo puede ser utilizado como transductor en un sistema de inmunosensor piezoeléctrico, para detectar uniones antígeno – anticuerpo. En este artículo se presenta una interfaz para microbalanzasde cristal de cuarzo, QCM (del inglés Quartz Crystal Microbalance) basado en una versión mejorada de oscilador en configuración diferencial equilibrado y su validación como sistema de caracterización para biosensores. El sistema fue probado con éxito en un inmunosensor piezoeléctrico para la detección del plaguicida Carbaryl.Montagut Ferizzola, YJ.; García Narbón, JV.; Jiménez Jiménez, Y.; March Iborra, MDC.; Montoya Baides, Á.; Torres Villa, RA.; Arnau Vives, A. (2011). Oscilador para biosensores basado en microbalanza de cristal de cuarzo (QCM). Facultad de Ingeniería. Universidad de Antioquia. 61:160-168. http://hdl.handle.net/10251/55018S1601686

A High Fundamental Frequency (HFF)-based QCM Immunosensor for Tuberculosis Detection

Tuberculosis, one of the oldest diseases affecting human beings, is still considered as a world public health problem by the World Health Organization. Therefore, there is a need for new and more powerful analytical methods for early illness diagnosis. With this idea in mind, the development of a High Fundamental Frequency (HFF) piezoelectric immunosensor for the sensitive detection of tuberculosis was undertaken. A 38 kDa protein secreted by Mycobacterium tuberculosis was first selected as the target biomarker. Then, specific monoclonal antibodies (MAbs) were obtained. Myc-31 MAb, which showed the highest affinity to the analyte, was employed to set up a reference enzyme-linked immunosorbent assay (ELISA) with a limit of detection of 14 ng mL-1 of 38 kDa antigen. For the development of the HFF piezoelectric immunosensor, 100 MHz quartz crystals were used as transducer elements. The gold electrode surface was functionalized by covalent immobilization of the target biomarker through mixed self-assembled monolayers (mSAM) of carboxylic alkane thiols. A competitive immunoassay based on Myc-31 MAb was integrated with the transducer as sensing bio-recognition event. Reliable assay signals were obtained using low concentrations of antigen for functionalization and MAb for the competitive immunoassay. Under optimized conditions, the HFF immunosensor calibration curve for 38 kDa determination showed a limit of detection as low as 11 ng mL-1 of the biomarker. The high detectability attained by this immunosensor, in the picomolar range, makes it a promising tool for the easy, direct and sensitive detection of the tuberculosis biomarker in biological fluids such as sputum.This study was supported by COLCIENCIAS (Colombia), Project no. 13335212865) and by AWSensors (Valencia, Spain). All of the authors: A. Montoya, C. March, Y.J. Montagut, M.J. Moreno, J.J. Manclus, A. Arnau, Y. Jimenez, M. Jaramillo, P. A. Marin and R.A. Torres declare that they have no conflict of interest.Montoya Baides, Á.; March Iborra, MDC.; Montagut Ferizzola, YJ.; Moreno Tamarit, MJ.; Manclus Ciscar, JJ.; Arnau Vives, A.; Jiménez Jiménez, Y.... (2017). A High Fundamental Frequency (HFF)-based QCM Immunosensor for Tuberculosis Detection. Current Topics in Medicinal Chemistry. 17(14):1623-1630. https://doi.org/10.2174/1568026617666161104105210S16231630171

Surface Generated Acoustic Wave Biosensors for the Detection of Pathogens: A Review

This review presents a deep insight into the Surface Generated Acoustic Wave (SGAW) technology for biosensing applications, based on more than 40 years of technological and scientific developments. In the last 20 years, SGAWs have been attracting the attention of the biochemical scientific community, due to the fact that some of these devices - Shear Horizontal Surface Acoustic Wave (SH-SAW), Surface Transverse Wave (STW), Love Wave (LW), Flexural Plate Wave (FPW), Shear Horizontal Acoustic Plate Mode (SH-APM) and Layered Guided Acoustic Plate Mode (LG-APM) - have demonstrated a high sensitivity in the detection of biorelevant molecules in liquid media. In addition, complementary efforts to improve the sensing films have been done during these years. All these developments have been made with the aim of achieving, in a future, a highly sensitive, low cost, small size, multi-channel, portable, reliable and commercially established SGAW biosensor. A setup with these features could significantly contribute to future developments in the health, food and environmental industries. The second purpose of this work is to describe the state-of-the-art of SGAW biosensors for the detection of pathogens, being this topic an issue of extremely importance for the human health. Finally, the review discuses the commercial availability, trends and future challenges of the SGAW biosensors for such applications

Monoclonal antibody-based flow-through immunosensor for analysis of carbaryl

[EN] Immunosensor systems have been developed for the rapid and sensitive determination of pesticides, using the insecticide carbaryl as a model analyte. The systems are based on the principle of heterogeneous competitive enzyme immunoassay and used mouse monoclonal anti-carbaryl antibodies either in solution (indirect format) or immobilized (direct format). In both formats, enzyme label (horseradish peroxidase, HRP) and fluorometric detection were employed. In the direct format, antibodies were immobilized on a hydrazide-derivatized agarose gel, and 6-[((1-naphthyloxy)carbonyl)amino]hexanoic acid (CNH hapten) conjugated to HRP was used as the enzyme tracer. The limit of detection was 26 ng L-1 (11 min/assay), and the useful life of the sensor was 60−70 cycles. In the indirect format, CNH conjugated to bovine serum albumin was immobilized on an N-hydroxysuccinimide-derivatized agarose gel, and a rabbit anti-mouse antibody labeled with HRP was used as a secondary immunoreagent. The limit of detection was 284 ng L-1 (17 min/assay), and the useful life of the sensor was 160−200 cycles. The developed methods were applied to the analysis of commercial drinking water and apple juice spiked with carbaryl. Interassay RSD ranged from 9 to 39% in the direct format and from 4 to 28% in the indirect format. Recoveries were between 62 and 109% in the direct format and between 78 and 124% in the indirect format. The results were compared with those obtained by enzyme-linked immunosorbent assay as reference method and indicated the suitability of the immunosensor for quality control in water and food analysisThis project was supported by the CICYT project AMB 96-1079 and the DGCYT project PB 95-0740. M.A.G.-M. acknowledges a grant from the Fundacio´n Caja Madrid to carry out Ph.D. studies.González Martínez, MÁ.; Morais, S.; Puchades, R.; Maquieira Catala, Á.; Abad Fuentes, A.; Montoya Baides, Á. (1997). Monoclonal antibody-based flow-through immunosensor for analysis of carbaryl. Analytical Chemistry. 69(14):2812-2818. https://doi.org/10.1021/ac961068tS28122818691

Development of monoclonal antibody-based immunoassays for the analysis of bisphenol A in canned vegetables

The aim of this work was the development of monoclonal antibodies (MAbs) and highly sensitive immunoassays (ELISAs) to bisphenol A (BPA), a well-known endocrine disruptor able to migrate from the internal coating of cans to food contained inside, particularly vegetables. To produce MAbs to BPA, four synthetic compounds were conjugated to proteins and used as immunizing haptens in mice. By applying hybridoma technology, several MAbs were produced and selected. These antibodies were characterized in the conjugate-coated and in the antibody-coated formats, using both homologous and heterologous conjugates. Three indirect ELISA based on the MAbs showing the highest affinity to BPA were selected. The limit of detection of the most sensitive ELISA was 0.22 nM (0.05 ng/mL), with an I50 value of around 1 nM (0.23 ng/mL). An homologous ELISA based on the MAb BPAB-11 was applied to the simple, direct determination of BPA in the liquid portion of canned artichoke, peas, and sweet corn. Only sample dilution in an appropriate saline buffer was required to minimize matrix effects and to enter the ELISA working range. Recovery and precision of the method were evaluated by spiking the liquid portion of these cans with BPA at 20, 50, and 100 ng/mL. Coefficients of variation were below 20% in most cases. With regard to recovery, the analytical data obtained were also acceptable. This immunoassay has therefore proved its potential as a new tool for the rapid, sensitive and accurate determination of BPA in canned food. © Taylor & Francis Group, LLC.This work was supported by the Spanish MICINN project No. AGL2006-13361Moreno Tamarit, MJ.; D'arienzo, P.; Manclus Ciscar, JJ.; Montoya Baides, Á. (2011). Development of monoclonal antibody-based immunoassays for the analysis of bisphenol A in canned vegetables. Journal of Environmental Science and Health, Part B. 46(6):509-517. https://doi.org/10.1080/03601234.2011.58387150951746

Development of an automated controlled-pore glass flow-through immunosensor for carbaryl

[EN] The application of controlled-pore glass (CPG) as solid support for immobilization of immunoreagents in order to develop flow-through immunosensors is described. Monoclonal antibodies (MAbs) to carbaryl were site-directed immobilized on CPG through covalent attachment of their oxidized carbohydrate moieties to amine groups generated on the surface of silanyzed CPG. The automated immunosensor system is based on the LIB-CNA36 MAb in a direct competitive assay format, with horseradish peroxidase as enzyme label and fluorimetric detection. The dynamic range of the sensor is 0.05-1 mu g l(-1), with a detection limit of 0.029 mu g l(-1), being sensitive enough to be applied to drinking water samples without preconcentration. The immobilized antibody reactor is able to run a whole assay in 20 min, and is reusable for more than 100 of consecutive assay cycles without significant loss of performance. The recognition of 1-naphthol -the main metabolite of carbaryl -and other N-methylcarbamate insecticides are also studied, none of these compounds showing cross-reactivity higher than 7%. A preliminary validation of the immunosensor, carried out by analysing real samples spiked with carbaryl, shows good results for bottled water and for commercial honey diluted with PBS (1 g l(-1)) as the only sample pretreatment.This project was supported by the CICYT project ALI 92-0417 and ALI 94-0673. M.A. González-Martínez acknowledge a grant from Fundación Cajamadrid, Spain, to carry out PhD studies.González Martínez, MÁ.; Morais, S.; Puchades, R.; Maquieira Giménez, M.; Abad Fuentes, A.; Montoya Baides, Á. (1997). Development of an automated controlled-pore glass flow-through immunosensor for carbaryl. Analytica Chimica Acta. 347(1):199-205. https://doi.org/10.1016/S0003-2670(97)00003-2S199205347