Categoría publications

Ion Dynamics at the Single Wall Carbon Nanotube Based Composite Electrode/Electrolyte Interface: Influence of the Cation Size and the Electrolyte pH

/in , /by

Authors: Freddy Escobar-Teran, Hubert Perrot, and Ozlem Sel
Journal: J. Phys. Chem C (2019)

Read more

Piezoelectric biosensors

/in , /by

Authors:  Petr Skládal

Department of Biochemistry, Faculty of Science, Masaryk University, Brno, Czech Republic

Journal: Trends in Analytical Chemistry

Abstract: Progress in the field of piezoelectric (quartz crystal microbalance-based) biosensors in the recent five years is reviewed. In addition to the traditional immunosensing assays, the combination with detection of nucleic acids is addressed, biosensing of microbes and novel applications in the field of cellular biology are highlighted. The signal enhancing strategies based on both biochemical cascades (often involving nanoparticles) and technological improvements of instrumentation are discussed.

Keywords: Quartz crystal microbalance, Immunosensor, Nucleic acid sensor, Eukaryotic cellular studies, Instrumentation for piezosensors

DOI: https://doi.org/10.1016/j.trac.2015.12.009

High Fundamental Frequency Quartz Crystal Microbalance (HFF-QCM) immunosensor for pesticide detection in honey

/in , /by

Authors:  Lourdes Cervera-Chinera , Marisol Juan-Borrása , Carmen Marchb , Antonio Arnaub , Isabel Escrichea,c, Ángel Montoyab , Yolanda Jiménezb

aInstituto de Ingeniería de Alimentos para el Desarrollo, Universitat Politècnica de València, Camino de Vera s/n, 46022, Valencia, Spain
bCentro de Investigación e Innovación en Bioingeniería (Ci2B), Universitat Politècnica de València, Camino de Vera s/n, 46022, Valencia, Spain
cFood Technology Department (DTA), Universitat Politècnica de València, Camino de Vera s/n, 46022, Valencia, Spain

Journal: Food Control (2018)

Abstract: Quantification of chemical residues in honey is a market requirement to ensure consumer safety. The most common method used to analyze these compounds is the LC/MS/MS methodology, which requires highly qualified technicians and a tedious pre-treatment of the sample. The honey-packaging industry needs cheaper and faster alternatives for routine control. HFF-QCM (High Fundamental Frequency Quartz Crystal Microbalance) sensors are becoming a good option due to their high sensitivity, fast detection and low cost, while avoiding complex sample pre-treatment. The HFF-QCM technology is based on piezoelectric sensors with frequencies in the range from several tenths of MHz to hundreds of MHz. In this work a 100 MHz HFF-QCM sensor was used in a monoclonal antibody-based competitive immunoassay for specific bio-recognition of carbaryl pesticide as testing contaminant. The work intends to validate the use of HFF-QCM technology, in comparison with liquid chromatography-tandem mass spectrometry (LC-MS/MS) technique, for the detection of contaminants in honey. For this purpose, the validation criteria required by SANCO 12571/2013 guidance document were considered. The precision and accuracy (recovery) of both methods were determined by comparison of 5 replicates at 4 different concentrations (from 0 to 100 μg/kg) using the same honey matrix. HFF-QCM technology showed good accuracy, with recovery percentages always between 110 and 120%. As regards to precision, HFF-QCM coefficients of variation (CV) were around 10% higher than those recommended by GC SANCO 12571/2013. HFF-QCM limits of detection (LOD) and quantification (LOQ) were in the same order of magnitude as those for LC-MS/MS, which allows the analysis of carbaryl residues in honey under the established maximum residue limits (MRL), without sample pre-treatment. These results show that biosensors based on HFF-QCM technology has become a serious alternative to the traditional analytical techniques for food quality and safety applications.

Keywords: High-fundamental-frequency QCM, Piezoelectric immunosensors, Carbaryl, Pesticides, Honey

Comparison of Aflatoxin B1 Measurement Efficiencies of 5 Mhz QCM and 120 Mhz Love Wave Sensors

/in , /by

Authors: Ş. Şeyda Pirinçci, Özlem Ertekin, Zafer Ziya Öztürk, Selma Öztürk

Conference: Fourth International Conference on Sensors and Electronic Instrumentation Advances (SEIA’ 2018)

Read more

Electro-Assisted Deposition of Calcium Phosphate on Self-Assembled Monolayers

/in , /by

Authors: Noah Metoki1, Kazi Sadman2, Kenneth Shull2, Noam Eliaz1 and Daniel Mandler3

1Biomaterials and Corrosion Lab, Department of Materials Science and Engineering, Tel-Aviv University, Ramat Aviv 6997801, Israel
2Polymer Surfaces & Inferfaces Lab, Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA
3Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel

Journal: Electrochimica Acta (2016)

Abstract: Calcium phosphate (CaP) ceramics are used in orthopedics and dentistry due to their excellent biocompatibility and osseointegration. Here, the electro-assisted deposition of CaP on two different selfassembled monolayers (SAMs), 2-mercaptoacetic acid (MAA) and 2-mercaptoethanol (ME), was studied both at short (up to 3 min) and long (2 hours) deposition periods on well-defined evaporated gold surfaces. It was found that the end group of the monolayer has a major effect on the growth of the CaP coating. The deposition was slower and less electrically efficient on MAA SAM, but surface cracking was essentially eliminated due to reduction of the crystallographic mismatch. The carboxylic acid may
facilitate CaP growth by attracting Ca2+ ions to the surface, which could explain the higher amount of side reactions occurring at the beginning of the deposition.

Keywords: Calcium phosphate (CaP), hydroxyapatite (HAp), electrodeposition, self- assembled monolayers (SAMs)

Design and Validation of a 150 MHz HFFQCM Sensor for Bio-Sensing Applications

/in , /by

Authors: Román Fernández1, Pablo García1, María García1, José V. García1, Yolanda Jiménez2 and Antonio Arnau2

1Advanced Wave Sensors S. L., Algepser 24, 46988 Paterna, Spain
2Centro de Investigación e Innovación en Bioingeniería, Universitat Politècnica de València, Camí de Vera S/N, 46022 Valencia, Spain

Journal: Sensors Journal (2017)

Abstract: Acoustic wave resonators have become suitable devices for a broad range of sensing applications due to their sensitivity, low cost, and integration capability, which are all factors that meet the requirements for the resonators to be used as sensing elements for portable point of care (PoC) platforms. In this work, the design, characterization, and validation of a 150 MHz high fundamental frequency quartz crystal microbalance (HFF-QCM) sensor for bio-sensing applications are introduced. Finite element method (FEM) simulations of the proposed design are in good agreement with the electrical characterization of the manufactured resonators. The sensor is also validated for bio-sensing applications. For this purpose, a specific sensor cell was designed and manufactured that addresses the critical requirements associated with this type of sensor and application. Due to the small sensing area and the sensor’s fragility, these requirements include a low-volume flow chamber in the nanoliter range, and a system approach that provides the appropriate pressure control for assuring liquid confinement while maintaining the integrity of the sensor with a good base line stability and easy sensor replacement. The sensor characteristics make it suitable for consideration as the elemental part of a sensor matrix in a multichannel platform for point of care applications.

Keywords: HFF-QCM (high fundamental frequency quartz crystal microbalance); finite element method (FEM); flow cell; biosensor; PoC (point of care); MQCM (monolithic quartz crystal microbalance)

 Sensors 17 02057 g002 550

You can download the full paper here

A liquid biopsy platform combining a high fundamental frequency QCM device with dynamic chemistry for detecting mutations in circulating DNA

/in , /by

Authors: A. Grammoustianou, G. Papadakis, M. Tabraue, J.J. Díaz-Mochon, R. Fernández, J.V. García, A. Arnau, E. Gizeli. AWSensors S.L., Institute of Molecular Biology and Biotechnology- FORTH, University of Crete, Destina Genomics S.L., Centro de Investigación e Innovación en Bioingeniería – Universidad Politécnica de Valencia

Event:  5th International Conference on Bio-sensing Technology, Riva del Garda, Italy (2017)

In the past decade, the analysis of circulating tumour DNA (ctDNA) in blood has been a major breakthrough; ctDNA has been proposed as a priceless source for cancer diagnostic, prognostic and treatment monitoring through a new methodology known as “Liquid Biopsy”. This study presents a novel diagnostic method for the acoustic detection of KRAS mutations in ctDNAs based on: (1) DNA analysis by “dynamic chemistry” that utilizes aldehyde modified nucleobases (SMART) and abasic peptide nucleic acids (DGL probes) capable for the errorfree detection of nucleic acids and their mutations; and, (2) a high fundamental frequency (100 MHz) acoustic wave microsensor (AWS HFF-QCM) that allows the accurate, inexpensive, label-free and real time monitoring of the “dynamic chemistry”. Surface-immobilized DGL probes on the AWS HFF-QCM device are used to detect ctDNAs of wild type and mutated KRAS variants. Upon hybridization of the DGL probe with its target ssDNA, a duplex is formed where biotin- tagged SMART bases can lock in front of the position under interrogation; streptavidin binding detected in a follow-up step confirms the presence of the SMART bases. The use of DGL probes in combination with an isothermal DNA amplification step RPA) have allowed the sensitive and specific recognition of single mismatches in KRAS genes in less than 1 hour. This work presents a unique and novel technology that can emerge as a promising tool in the field of cancer diagnostics.

Liquid Biopsy detection protocol

Schema for complete detection protocol:

(A) Extracted DNA containing mutant (red) and wild type DNA fragments (black) are enzymatically amplified.

(B) Denatured amplicons are hybridized on surface immobilized DGL probes. Chemical locking of a specific tagged SMART base takes place only in the appropriate position.

(C) Incorporated SMART bases are recognized by streptavidin and monitored in real-time during an acoustic measurement.

A High Fundamental Frequency QCM Immunosensor for Tuberculosis Detection

/in , /by

AWSensors biosensor for tuberculosis detection

Authors: Ángel Montoya, Carmen March, Yeison J. Montagut, Maria J. Moreno, Juan J. Manclus, Antonio Arnau, Yolanda Jiménez, Marisol Jaramillo, Paula A. Marin, Robinson A. Torres

Journal:  Current topics in Medicinal Chemistry (2017)

Background: Tuberculosis, one of the oldest diseases affecting human beings, is still considered as a world public health problem by the World Health Organization.

Method & Material: 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.

Results & Discussion: For the development of the HFF piezoelectric immunosensor, 100 MHz AWSensors 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.

You may review the full paper here

Dynamic Resolution of Ion Transfer in Electrochemically Reduced Graphene Oxides Revealed by Electrogravimetric Impedance

/in , /by

Authors: Hamza Goubaa, Freddy Escobar-Teran, Ibtissam Ressam, Wanli Gao, Abdelkrim el Kadib, Ivan T. Lucas, Mustapha Raihane, Mohammed Lahcini, Hubert Perrot, Ozlem Sel. Sorbonne Université, UPMC, Univ Paris 06, CNRS, France. Laboratoire Interfaces et Systèmes Électroquimiques; Université Cadi Ayyad, Faculté des Sciences et Techniques, Laboratoire de Chimie Organométallique et Macromoléculaire Matériaux composites, Marrakech, Morocco.

Journal:  The Journal of Physical Chemistry (2017)

To accompany the search for optimal materials in electrochemical supercapacitors, appropriate characterization tools to assess key parameters of newly developed electrodes are required. Here we demonstrate the capabilities of ac-mode electrogravimetry to study in details the capacitive charge storage mechanisms in electrochemically reduced graphene oxide (ERGO) thin films electrodes. The coupling of electrochemical impedance spectroscopy (EIS) with fast quartz crystal microbalance (QCM) complements classical electrochemical quartz crystal microbalance (EQCM) by capturing here the dynamics of the electroadsorption process, identifying charged moieties and detecting solvation effects. We evidenced the co-electroadsorption of two types of cationic species (fully and partially hydrated cations) in the potential range studied and the indirect intervention of free solvent molecules. Further kinetic information on electroadsorption is also obtained which leads to a full deconvolution of the global EQCM response at both gravimetric and temporal level. Through a fine analysis of the interactions of different cations of period one elements, Li+, Na+ and K+ with ERGO, we evidenced the critical role of solvation processes on the kinetics of electroadsorption, and provided an experimental proof to the phenomena that smaller ions are more tightly bound to their water molecules such that an inverse relationship exists between the dehydration energy and the ion size. Such gravimetric and dynamic subleties are unreachable with classical tools and with EQCM method alone which permits us to suggest the ac-mode electrogravimetry as a baseline diagnostic tool to explore charge transfer mechanisms at the nanoscale.

Electrochemical and viscoelastic evolution of dodecyl sulfate-doped polypyrrole films during electrochemical cycling

/in , /by

Authors: Wanli Gao, Ozlem Sel, Hubert Perrot

Journal:  Electrochimica Acta (2017)

The correlation between electrochemical and viscoelastic properties of electrodeposited dodecysulfatedoped polypyrrole (PPy-DS) during electrochemical cycling process was described through combining electrochemical quartz-crystal microbalance (EQCM), ac-electrogravimetric characterizations and electroacoustic measurements. as the PPy-DS electrode evolves during the course of consecutive cycling in aqueous NaCI electrolyte, the film exhibits (i) an obvious ion-selective transition from cations to anions in the charge compensation process; (ii) an inferior electrochemical performance accompanied with increased stiffness (increased storaged moduli, G’); and (iii) depleted capability of ionic exchange through film/electrolyte interface. PPy-DS conducting polymer electrodes (CPEs) are of interest in energy storage and the relationship between electrochemical and viscoelastic properties during electrochemical cycling process is essential for promoting the performance of these devices. In this perspective, ac-electrogravimetry combined with electroacoustic measurements can be suggested as an alternative method to synchronously probe the electrochemical and mechanical evolution and has the potential to offer a generalized route to study aging mechanism of CPEs.