Categoría publications

Ultraflat Gold QCM Electrodes Fabricated with Pressure-Forming Template Stripping for Protein Studies at the Nanoscale

Authors: Juan A. Rubio-Lara, Frederik Bergler, Simon J. Attwood, J. Michael Edwardson, Mark E. Welland


Journal: Langmuir, 2019

Validation of quartz crystal rheometry in the megahertz frequency regime

Authors: David E. Delgado, Lauren F. Sturdy, Craig W. Burkhart, Kenneth R. Shull

Journal: Inc. J. Polym. Sci., Part B: Polym. Phys. 2019

Versatile and High-Throughput Polyelectrolyte Complex Membranes via Phase Inversion

Authors: Kazi Sadman, David E. Delgado, Yechan Won, Qifeng Wang, Kimberly A. Gray, Kenneth R. Shull


Journal: ACS Appl. Mater. Interfaces, 2019, 11(17), 16018-16026.

3D-printed Point-of-Care Platform for Genetic Testing of Infectious Diseases Directly in Human Samples Using Acoustic Sensors and a Smartphone

Authors:
George Papadakis, Alexandros K. Pantazis, Maria Ntogka, Konstantinos Parasyris, Gesthimani-Ioanna Theodosi, Georgia Kaprou, Electra Gizeli

Journal:
ACS Sens. 2019451329-1336

Examination of High Frequency MHz Rheology of Filled Polymer Composites and Photopolymers

Author:
Chyi-Huey Joshua Ye

Ph.D. Thesis

Northwestern University, Department of Materials Science and Engineering, September, 2017

Tuning Charge Storage Properties of Supercapacitive Electrodes Evidenced by In Situ Gravimetric and Viscoelastic Explorations

Journal:  Anal. Chem.

Authors:  FWanli Gao, Catherine Debiemme-Chouvy, Mohammed Lahcini, Hubert Perrot, and Ozlem Sel

Abstract: Revealed by an integrated electrogravimetric and viscoelastic method, slightly electrochemically reduced graphene oxide (ERGO) presents an anion preference for charge storage and delivery, while with the progressive removal of oxygen functionalities on its basal planes, cations begin to predominate in charge compensation. This “anion-to-cation” evolution in neutral aqueous media can not only affect the electrochemical charge storage, but also play an important role in electrode’s viscoelasticity. It was demonstrated that oxygen functionalities could modify the interactions between graphene layers and even contribute to pseudocapacitances. However, the role of oxygen functionalities in species transfer and viscoelastic variations still remains poorly understood. Herein, a combined methodology of electrochemical quartz crystal microbalance (EQCM), ac-electrogravimetry and electroacoustic impedance measurements was proposed for characterizing the electrochemical and viscoelastic responses of graphene oxides with various degree of electrochemical reduction. With the removal of oxygen containing functional groups, ERGO electrode exhibits (i) a gradually enhanced specific capacitance (Cs) with increased flexibility (decreased storage moduli, G′); (ii) a dehydration process of cations (i.e., from Na+·2H2O to Na+·H2O); and (iii) a potential-dependent “stiffened-softened” behavior. These results open the door for a suitable design of GO-based materials for electrochemical energy storage and shed light on electronic devices where ion-selective behavior plays a key role.Keywords: Electrochemical Quartz crystal microbalance, ,

Link: https://pubs.acs.org/doi/abs/10.1021/acs.analchem.8b04886

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

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

Piezoelectric biosensors

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

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

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

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

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)