This review covers advances in electrochemical and biochemical sensor development and usage during 2010 and 2011 In choosing scholarly articles to contribute to this review, special emphasis was placed on work published in the areas of reference electrodes, potentiometric sensors, voltammetric sensors, amperometric sensors, biosensors, immunosensors, and mass sensors In the past two years there have been a number of important papers, that do not fall into the general subsections contained within the larger sections Such novel advances are very important for the field of electrochemical sensors as they open up new avenues and methods for future research Each section above contains a subsection titled “Other Papers of Interest” that includes such articles and describes their importance to the field in general For example, while most electrochemical techniques for sensing analytes of interest are based on the changes in potential or current, Shan et al1 have developed a completely novel method for performing electrochemical measurements In their work, they report a method for imaging local electrochemical current using the optical signal of the electrode surface generated from a surface plasmon resonance (SPR) The electrochemical current image is based on the fact that the current density can be easily calculated from the local SPR signal The authors demonstrated this concept by imaging traces of TNT on a fingerprint on a gold substrate

Full articles and reviews were primarily amassed by searching the SciFinder Scholar and ISI Web of Knowledge Additional articles were found through alternate databases or by perusing analytical journals for pertinent publications Due to the reference limitation, only publications written in English were considered for inclusion Obviously, there have been more published accounts of groundbreaking work with electrochemical and biochemical sensors than those covered here This review is a small sampling of the available literature and not intended to cover every advance of the past two years The literature chosen focuses on new trends in materials, techniques, and clinically relevant applications of novel sensors To ensure proper coverage of these trends, theoretical publications and applications of previously reported sensor development were excluded

We want to remind our readers that this review is not intended to provide comprehensive coverage of electrochemical sensor development, but rather to provide a glimpse of the available depth of knowledge published in the past two years This review is meant to focus on novel methods and materials, with a particular focus on the increasing use of graphene sheets for sensor material development For readers seeking more information on the general principles behind electrochemical sensors and electrochemical methods, we recommend other sources with a broader scope2, 3 Electrochemical sensor research is continually providing new insights into a variety of fields and providing a breadth of relevant literature that is worthy of inclusion in this review Unfortunately, it is impossible to cover each publication and unintentional oversights are inevitable We sincerely apologize to the authors of electrochemical and biochemical sensor publications that were inadvertently overlooked

Electrochemical Sensors and Biosensors

A new metamaterial-inspired microwave microfluidic sensor is proposed in this paper. The main part of the device is a microstrip coupled complementary split-ring resonator (CSRR). At resonance, a strong electric field will be established along the sides of CSRR producing a very sensitive area to a change in the nearby dielectric material. A micro-channel is positioned over this area for microfluidic sensing. The liquid sample flowing inside the channel modifies the resonance frequency and peak attenuation of the CSRR resonance. The dielectric properties of the liquid sample can be estimated by establishing an empirical relation between the resonance characteristics and the sample complex permittivity. The designed microfluidic sensor requires a very small amount of sample for testing since the cross-sectional area of the sensing channel is over five orders of magnitude smaller than the square of the wavelength. The proposed microfluidic sensing concept is compatible with lab-on-a-chip platforms owing to its compactness.

/pdf/high-sensitivity-metamaterial-inspired-sensor-for-2kb4swmrvp.pdf

High-Sensitivity Metamaterial-Inspired Sensor for Microfluidic Dielectric Characterization

Metamaterials are artificial media structured on a size scale smaller than wavelength of external stimuli, and they can exhibit a strong localization and enhancement of fields, which may provide novel tools to significantly enhance the sensitivity and resolution of sensors, and open new degrees of freedom in sensing design aspect. This paper mainly presents the recent progress concerning metamaterials-based sensing, and detailedly reviews the principle, detecting process and sensitivity of three distinct types of sensors based on metamaterials, as well as their challenges and prospects. Moreover, the design guidelines for each sensor and its performance are compared and summarized.

https://www.mdpi.com/1424-8220/12/3/2742/pdf

Metamaterials application in sensing.

Herein, we present a survey of the literature covering the development of molecular imprinting science and technology over the years 2004-2011. In total, 3779 references to the original papers, rev ...

Molecular imprinting science and technology: a survey of the literature for the years 2004-2011.

Advances in carbon nanotube based electrochemical sensors for bioanalytical applications.

A microfluidic sensor is implemented from a single split-ring resonator (SRR), a fundamental building block of electromagnetic metamaterials. At resonance, an SRR establishes an intense electric field confined within a deeply subwavelength region. Liquid flowing in a micro-channel laid on this region can alter the local field distribution and hence affect the SRR resonance behavior. Specifically, the resonance frequency and bandwidth are influenced by the complex dielectric permittivity of the liquid sample. The empirical relation between the sensor resonance and the sample permittivity can be established, and from this relation, the complex permittivity of liquid samples can be estimated. The technique is capable of sensing liquid flowing in the channel with a cross-sectional area as small as (0.001 λ 0 ) 2 , where λ 0 denotes the free-space wavelength of the wave excitation. This work motivates the use of SRR-based microfluidic sensors for identification, classification, and characterization of chemical and biochemical analytes.

/pdf/metamaterial-based-microfluidic-sensor-for-dielectric-36tegw4pj2.pdf

Metamaterial-based microfluidic sensor for dielectric characterization

A review of monolithic multichannel quartz crystal microbalance: a review.

A multichannel thin-film sensor is implemented from a set of microstrip-coupled split-ring resonators (SRRs) with different dimensions. Each SRR exhibits a unique high-Q resonance that is sensitive to the presence of a sample in a particular area. Hence, this SRR-based sensor can function (i) to detect different samples simultaneously to increase the throughput or (ii) to characterise nominally identical samples at multiple frequencies to increase the sensor selectivity. In addition, the sensitivity of this SRR-based sensor is optimized through strategic design of the resonator shape to produce a strong confined electric field at each sensing region. The design principle is validated with simulation and measurement. Owing to the optimized design, sensing a low-permittivity film with a thickness as small as one thousandth of the operating wavelength is achievable.

/pdf/metamaterial-inspired-multichannel-thin-film-sensor-4rgigvibec.pdf

Metamaterial-Inspired Multichannel Thin-Film Sensor

https://www.nectec.or.th/mems/download/Flow%20Injection%20based%20Microfluidic.pdf

Kata Jaruwongrungsee

Papers

Metamaterial-based microfluidic sensor for dielectric characterization

A review of monolithic multichannel quartz crystal microbalance: a review.

Metamaterial-Inspired Multichannel Thin-Film Sensor

Flow injection based microfluidic device with carbon nanotube electrode for rapid salbutamol detection

Piezoresistive microcantilever-based DNA sensor for sensitive detection of pathogenic Vibrio cholerae O1 in food sample