bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of Single-Stranded DNA and PNA Probes for Electrochemical Detection of miRNA 141
Authors: Jarczewska Marta , Bojarski Wiktor , Majewska Aleksandra , Mieczkowska Magdalena , Drozd Marcin , Ziolkowski Robert , Malinowska Elżbieta 
Published: July 2022

miRNA are known as short RNA molecules that usually consist of 18 – 25 nucleotides and are considered as posttranscriptional regulators of gene expression occurring in plants and animals [1]. Over 60% of all genes which encode proteins are controlled by miRNA [2]. miRNA is engaged in various processes including differentiation, proliferation and apoptosis as well as inflammation. Hence, they might be considered as potential biomarkers of diseases such as cancer, neurodegenerative and cardiovascular [3]. A huge challenge is the actual detection of miRNA because of their short length, low concentration and matrix interferences. The miRNA analysis can be performed with the following techniques such as real-time PCR, northern blotting and microarray [4-6]. However, the above mentioned techniques are rather sophisticated and are costly. An alternative could be the application of electrochemical techniques which are characterized with low detection limits, possibility of miniaturization and high sensitivity. In such a case miRNA could be detected using biosensors containing receptor layers formed of single-stranded DNA or PNA.
Herein, we present the studies on the development of ssDNA/PNA – based receptor layers for the electrochemical analysis of miRNA 141, which is a biomarker of pancreatic cancer. Various receptor layers were tested including unlabelled ssDNA, methylene blue-labelled DNA as well as PNA-based. The formation of ssDNA/PNA receptor layer along with its binding to miRNA was confirmed using QCM and SPR techniques. The electrochemical studies revealed that it was not possible to obtain low detection limits for miRNA when MB-labelled ssDNA or PNA molecules were applied. On the contrary, detection limit of 10-4 nM was reached with the application of unlabelled ssDNA molecules. The further analysis showed the possibility of detection of point mutation in ssDNA or miRNA sequence as well as miRNA detection in spiked serum sample.
Bibliography:
[1] D. P. Bartel, Cell 116 (2004) 281–297
[2] A. Krek, D. Grun, M. N. Poy, R. Wolf, L. Rosenberg, E. J. Epstein, P. MacMenamin, I. da Piedade, K. C. Gunsalus, M. Stoffel, N. Rajewsky, N. Nat. Genet. 37 (2005) 495−500.
[3] H. Hwang, J. T. Mendell, Br. J. Cancer 94 (2006) 776–780.
[4] C. Chen, D. A. Ridzon, A. J. Broomer, Z. Zhou, D. H. Lee, J. T. Nguyen, M. Barbisin, N. L. Xu, V. R. Mahuvakar, M. R. Andersen, K. Q. Lao, K. J. Livak, K. J.Guegler, Nucleic Acids Res. 33 (2005) e179
[5] A. Valoczi, C. Hornyik, N. Varga, J. Burgyan, S. Kauppinen, Z. Havelda, Nucleic Acids Res. 32 (2004) e175
[6] A. M. Krichevsky, K. S. King, C. P. Donahue, K. Khrapko, K. S.Kosik, RNA 9 (2003) 1274−1281.
(Digital Presentation) Electrocatalytic Cortisol Tracing Smart Patch
Authors: Yeasmin Sanjida , WU Bo , Ullah Ahasan , Zhang Boxin , Cheng Li-Jing 
Published: July 2022

Rapid and continuous tracking of the stress hormone cortisol's circadian rhythm is vital for diagnosing diseases related to chronic stress and adrenal gland disorders [1]. Commercial cortisol sensors relying on labeled enzyme and antibodies suffer from limited stability, lengthy reaction time, and cross-reactivity with analogous molecules [2]. To address these issues, we developed an electrocatalytic sensor using phthalocyanine (Pc) doped molecularly imprinted polymer (MIP) modified screen-printed electrodes for label-free, reagentless, sensitive, and selective electrochemical detection of cortisol. The sensor was constructed via one-step electropolymerization of conductive prepolymer in the presence of Pc and template cortisol. The controlled release of cortisol templates resulted in an MIP network embedded with Pc catalysts in the vicinity of the cortisol-specific binding cavities. The sensor directly measures the cortisol level by catalysing the reduction reaction of the cortisol captured by the cavities of the MIP. Proof of studies was performed to detect cortisol over a wide concentration range varying from 500 pM to 10 µM with high selectivity against structurally similar hormones. The facile label-free and antibody-free cortisol sensor on a wearable smart patch offers an appealing approach for selective steroid hormone detection at point-of-care testing.
References
[1] Liu, Ye, et al. "Label-Free Sensitive Detection of Steroid Hormone Cortisol Based on Target-Induced Fluorescence Quenching of Quantum Dots." Langmuir 36.27 (2020): 7781-7788.
[2] Manickam, Pandiaraj, et al. "A reusable electrochemical biosensor for monitoring of small molecules (cortisol) using molecularly imprinted polymers." Journal of the Electrochemical Society 164.2 (2016): B54.

Figure 1
(Digital Presentation) Electrochemical Sensors for Hydrogen/Deuterium Speciation
Authors: Pallarès Enric Lujan , Hinojo Antonio , Colominas Sergi , Abella Jordi 
Published: July 2022

By the end of the century, global energy demand is expected to increase by a factor of three due to population growth. In this context, fossil fuels should not be the main power source due to the elevated environmental cost. Nuclear fusion technology is planned as an alternative to this demand as it is expected to generate large quantities of energy without all the inconveniences of fossil fuels. The most feasible reaction to take place is the fusion between two hydrogen nuclei. Specifically, deuterium and tritium will react releasing helium, neutrons, and large amounts of energy [1].

2H + 3H → 4He + n + 17.59 MeV (1)
In the present work, BaCe0.6Zr0.3Y0.1O3-α electrolyte (BCZY) was used to construct amperometric sensors for hydrogen monitoring. Firstly, BCZY powder was synthesized by the solid-state method and characterized using SEM and XRD. Secondly, it was sintered as a pellet and bound to an alumina tube to construct the electrochemical sensors. Finally, amperometric measurements were performed inside a stainless-steel reactor at 500 °C and applying 0.15 V between electrodes. The response of the sensors was evaluated using hydrogen and deuterium calibration mixtures. The concentration in the WE ranged from 150 to 300 ppm H2 or D2 in Ar. Argon was used in the CE as a cover gas. Finally, measurements with hydrogen and deuterium were compared to determine the isotope effect on the response.
[1] J.Kenneth. Shultis, R.E. Faw, Fundamentals of nuclear science and engineering, Marcel Dekker, 2002.
[2] E.C.C. de Souza, R. Muccillo, Properties and applications of perovskite proton conductors, Materials Research. 13 (2010) 385–394. https://doi.org/10.1590/S1516-14392010000300018.
[3] A. Benes, A. Molinari, R. Witte, R. Kruk, J. Brötz, R. Chellali, H. Hahn, O. Clemens, Proton Conduction in Grain-Boundary-Free Oxygen-Deficient BaFeO2.5+δ Thin Films, Materials. 11 (2017) 52. https://doi.org/10.3390/ma11010052.
[4] A. Hinojo, I. Soriano, J. Abellà, S. Colominas, Evaluation of High-Temperature Hydrogen Sensors Based on BaCe0.6Zr0.3Y0.1O3-α and Sr(Ce0.9Zr0.1)0.95Yb0.05O3-α Perovskites for Industrial Applications, Sensors. 20 (2020) 7258. https://doi.org/10.3390/s20247258.
Performance Estimation Method of Li-Ion Starting-Lighting-Ignition Batteries of Electric Vehicle through Lab-Scale Pouch Cell Experiment
Authors: Oh Hyeseong , Gil Naeun , Kim Daeun , Jeong Kyeong-Min 
Published: July 2022

CCA (cold-cranking amps) is used as one of the standards to define the power of a SLI (starting-lighting-ignition) battery of electric vehicles (EVs) by applying a large discharge current for a short time. It is easier to start an engine at a high temperature than a low temperature, so tests are usually conducted at a low temperature to meet the demands of users. However, in a large cell, the internal temperature of the cell rises due to the heat of the cell when a large current is applied. This phenomenon can increase the overall cell power performance because it has the effect of reducing ohmic overvoltage and improving electrode kinetics. Therefore, it is difficult to distinguish the effect of the temperature rise and applied current on the voltage curve during the consecutive pulse discharge.
In this study, three times of 10 C discharge current pulse (~ 7 mA/cm2 in this study) is applied on a cell for 30 seconds, with rest periods of 600s, 30s included between each pulse. Evaluations were conducted from -18 ℃ to 50 ℃, with a LiFePO4/graphite lab-scale pouch cell rather than an actual large cell. Therefore, the temperature of the cell remained constant under the evaluation conditions in which heat generation is almost zero, so the voltage curves can be interpreted by excluding the effect of the temperature rise of a cell. Based on these experimental results, voltage curves were simulated depending on each internal resistance that related to Joule heating of the actual large cell. It is possible to predict the performance and degree of temperature rise of large cells. Also, this study proposes an effective and economical method to distinguish the effect of the temperature rise of the large cell and the applied current by using a lab-scale pouch cell with controlled temperature.
Understanding Behavior of Cathode Active Materials with Different Particle Sizes in Mixed Electrode through Current Distribution Measurement
Authors: Gil Naeun , Jeong Kyeong-Min 
Published: July 2022

The performance of a lithium-ion battery can be improved by mixing two or more kinds of cathode active materials in one electrode. In particular, energy density can be increased by mixing active materials having different particle sizes because the electrode can be filled with more active materials. As the performance of a battery is determined by the combination of the properties of the material itself and the electrode design conditions, it is most important to understand the characteristics of the material and the electrode independently. However, since the potential in a mixed electrode is measured as the mixed potential of each active material, it is not easy to identify how each active material behaves electrochemically under the current load condition.
In this experiment, we attempted to separate only the effects of active materials while minimizing the influence of the electrode density, which affects the mass transfer in the porous electrode. For this purpose, two electrodes consisting of small and large particles are placed in one pouch cell and connected in parallel with Li metal as a counter electrode. By measuring the current flowing through each electrode individually, we observed how small and large particles work in mixed electrode.
Since the influence of mass transfer inside the electrode was minimized, it was assumed that the mass transfer did not affect the currents divided into each electrode. Thus, current flowing to each electrode is determined by the relative contributions of charge transfer and solid diffusion kinetics. Large particles have smaller charge transfer resistance and slower solid diffusion than small particles. If rate-liming step is charge transfer, more currents flow to large particles by small charge transfer resistance. If rate-limiting step is solid diffusion, more currents flow to small particles due to the fast diffusion in active materials. Through this experiment, we could analyze the behavior of active materials having different particle sizes in mixed electrode by detecting the current respectively.
Study of Improving the Thermal Stability of Ceramic Coated Separator Via Chemical Crosslinking between Ceramic Particles and Polymeric Binders
Authors: Roh Youngjoon , Jin Dahee , Byun Seoungwoo , Ryou Myung-Hyun , Lee Yong Min 
Published: July 2022

Lithium-ion batteries (LIBs) are used in everyday applications such as portable electronics and electric vehicles (EVs) in our daily life. In large-scale batteries such as EVs, high energy density has been developed to secure longer mileage with one charge. Securing battery safety becomes extremely challenging as densifying the cell energy and increasing the battery. The safety of batteries must be guaranteed from the cell to the module, the pack, and the system, and it must not be ignored at every step. The separator is highlighted at the cell level as it plays an essential part in safety. To guarantee the safety of large-scale LIBs, it is essential to employ a ceramic-coated separator (CCS). To secure thermal stability using CCSs, the certain thickness of ceramic coating layer (CCL) is required. In contrast, the thicker CCL can act as a resistive layer in the cell, and in the worst case, the ceramic that has fallen off the CCS surface can act as a side reactant in the cell. However, if the CCL is thin, the desired thermal stability may not be obtained. The key technology is to improve adhesion while reducing the thickness of the CCL.
For this purpose, polydopamine nano layer is preliminary introduced on the surface of ceramic particles via simple solution polymerization. Then, poly(acrylic acid) binder, which can react with amine groups in polydopamine, is chosen for aqueous ceramic coating slurry. Thus, this combination can make several crosslinking points within CCL, which lead to higher adhesion within the CCL after electrolyte impregnation. As a result, the adhesion within the CCL of cross-linked CCS is increased by 70% compared to the non-crosslinked CCS. Furthermore, the adhesion does not decrease when impregnated with the electrolyte. Also, cross-linked CCS showed better shrinkage property than commercialized CCS with the same composition because the cross-linked CCS did not shrink even when exposed for 1 hour at a high temperature of 160 °C. From this study, with crosslinking reaction within coating layer, it is possible to improving heat resistance and physical properties of separator without increasing thickness of CCL.
Understanding of the Furfural Electrochemical Hydrogenation and Hydrogenolysis System in a Semi-Batch Reactor
Authors: May Andrew S. , Biddinger Elizabeth J. 
Published: July 2022

Furfural (FF) is a platform molecule that can undergo electrochemical hydrogenation and hydrogenolysis (ECH) over copper catalysts to form furfuryl alcohol (FA) and 2-methylfuran (FA) respectively. FA is a fine chemical used in creating furanic molds, and MF has been identified as a fuel candidate. An acidic electrolyte is necessary to obtain the MF product, however the acidic conditions are also the cause of homogeneous side reactions [1,2]. In our group we studied the kinetics of the FF ECH reactions in a 2-compartment H-cell connected to a solvent trap with inert gas sparging into the catholyte to promote the evaporation of MF to the solvent trap for capture. We showed the kinetics of the FF ECH reactions in 0.1 and 0.5M H2SO4 with concentrations of FF between 10 and 120 mM at -560mV vs RHE followed a non-competitive Langmuir-Hinshelwood model [3], in timeframes where side reactions did not influence the results significantly.
In this work, we build on our previous kinetic study by modeling the system of competing reactions and MF transfer to the solvent trap. We show the importance of sparging inert gas into the catholyte to promote evaporation of MF for collection in the solvent trap to avoid side reactions of MF in the acidic catholyte.
[1] Jung, Sungyup, and Elizabeth J. Biddinger. "Electrocatalytic hydrogenation and hydrogenolysis of furfural and the impact of homogeneous side reactions of furanic compounds in acidic electrolytes." ACS Sustainable Chemistry & Engineering 4, no. 12 (2016): 6500-6508
[2] Jung, Sungyup, and Elizabeth J. Biddinger. "Controlling competitive side reactions in the electrochemical upgrading of furfural to biofuel." Energy Technology 6, no. 7 (2018): 1370-1379
[3] May, Andrew S., Steven M. Watt, and Elizabeth J. Biddinger. "Kinetics of furfural electrochemical hydrogenation and hydrogenolysis in acidic media on copper." Reaction Chemistry & Engineering 6, no. 11 (2021): 2075-2086
Niobium Oxide Coated Mesoporous Platinum Nanoparticles for the Oxygen Reduction Reaction
Authors: Kilham Annabelle Maria , Gautam Sakshi , Gates Byron D. 
Published: July 2022

Effective and economic methods of converting chemical energy into electricity or vice versa (i.e., through the use of fuel cells) must be developed to aid in the transition to renewable energy sources. One of the major barriers in the commercialization of fuel cells is the disparity in speed and efficiency between the two fuel cell reactions: the hydrogen oxidation reaction (HOR) and the oxygen reduction reaction (ORR) of which the latter is orders of magnitude slower.1 Mesoporous Pt prepared by electrodeposition has been shown to have increased activity towards the ORR than the industry standard Pt nanoparticles (NPs) supported on carbon.2 Platinum based catalysts, however, lack long term stability under acidic fuel cell conditions. One method that has been found to mitigate the long-term loss of Pt catalyst stability and activity is coating platinum with nanoscale thin films of niobium oxide.3 In this work, niobium oxide was investigated as a stabilizing coating for mesoporous Pt NP catalysts.
Mesoporous Pt NPs were synthesized via electrodeposition to form ~50 nm diameter NPs. The Pt NPs were then coated with niobium oxide films with a varying nanoscale thickness that ranged from 3 to 50 nm. The niobium oxide films were fabricated using atomic layer deposition (ALD) or electrodeposition.3,4 Scanning electron microscopy and transmission electron tomography were used to evaluate the porosity and surface morphology of the Pt NPs before and after coating with niobium oxide. X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy were used to confirm the presence and composition of the niobium oxide films. Electrochemical characterization by cyclic voltammetry and electrochemical impedance spectroscopy under acidic conditions was used to determine an optimal thickness of the niobium oxide film that stabilizes the size and morphology of the Pt NPs while maintaining catalyst activity. The Pt NPs coated with <10-nm thick niobium oxide films were observed to have an increased long-term performance in comparison to their uncoated counterparts. Stabilizing NP catalysts for improving their long-term activity is a vital step towards creating affordable alternatives to fossil fuels by maximizing renewable energy resources.

Debe, M. K. Electrocatalyst Approaches and Challenges for Automotive Fuel Cells. Nature
2012, 486, 43–51.

Paul, M. T. Y.; Gates, B. D. Mesoporous Platinum Prepared by Electrodeposition for Ultralow Loading Proton Exchange Membrane Fuel Cells. Sci. Rep.
2019, 9, 4161.

Eastcott, J.; Gates, B. D. Nanoscale Thin Films of Niobium Oxide on Platinum Surfaces: Creating a Platform for Optimizing Material Composition and Electrochemical Stability. Can. J. Chem.
2017, 96, 260–266.

Zhitomirsky, I. Electrolytic Deposition of Niobium Oxide Films. Mater.
Lett.
1998, 35, 188–193.
Mixed Metal Ni(M)/YSZ for High-Temperature CO2 Electroreduction to CO
Authors: Kamboj Vipin , Ranjan Chinmoy 
Published: July 2022

Electroreduction of CO2 to fuels using renewable energy can significantly help in reducing emissions and dependence on fossil fuels. Electrochemical reduction of CO2 to hydrocarbon fuels (CHx) is energy inefficient owing to the multistep-multielectron transfer process, which possesses many kinetic limitations. The selective conversion of CO2 to CO is energy efficient. CO as product can be directly used as a fuel or converted to hydrocarbon fuels by using green hydrogen via Fischer-Tropsch reactions. We have used Ni(M)x/YSZ based electrodes to study electroreduction of CO2 on solid oxide cells at high temperature (~800∘C). Electrodes were developed on commercial standard YSZ supports using Ni(M)x/YSZ mixtures for cathode and LSM/YSZ mixtures for the anode. Electron microscopy and X-ray diffraction were used to characterize the electrode architecture and material.
The electrodes were tested using online mass spectroscopy and operando Raman spectroscopy. Ni/YSZ electrodes showed sustained performance only when H2 was added to the fuel mixture, and the reaction proceeded through a reverse water gas shift reaction (RWGS) (CO2 + H2
→ CO + H2O) in conjunction with water electrolysis with the CO originating from non-electrochemical RWGS reaction.
The reactions were also analyzed using electrochemical impedance spectroscopy. The pure Ni/YSZ cathodes showed deactivation under a pure CO2 atmosphere with the formation of NiOx species with the catastrophic breakdown at high current densities around 400 mA/cm2. The behaviour could be verified using both mass spectroscopy and operando Raman Spectroscopy. The electrochemical performance of various electrodes was compared using a 3-electrode geometry. Mixed metal oxide electrodes such as Ni(M) showed improved kinetics, with significant improvement seen in the charge transfer resistance measured.

Figure 1
Multi-Scale Modeling of Hydrogen Transport in a Porous Fuel Cell Anode
Authors: Zhang Rosa , Chowdhury Anamika , Bui Justin C , Radke Clayton J. , Weber Adam Z. 
Published: July 2022

Proton-exchange-membrane fuel cells (PEMFC) are a clean energy conversion alternative to traditional fossil-fuel combustion; however, transport resistances in the electrode pose a lower-limit to catalyst loading and commercialization of PEMFCs. PEMFCs consist of simultaneous hydrogen (H2) oxidation and oxygen (O2) reduction at the anode and cathode, respectively. While oxygen transport resistances in PEMFCs have been widely studied both experimentally and analytically, hydrogen transport resistances are less understood. Herein, we present a physics-based model that encompasses multi-scale transport within the anode side of the PEMFC. The O2 in the cathode here is omitted and replaced with H2 to deconvolute O2 transport resistance contributions, similar to that of a hydrogen pump. Replication of the hydrogen pump setup allows for comparison of the model against experimental analysis of H2 gas-transport resistance in H2 limiting-current experiments, which can also inform gas transport (including oxygen) in general. Herein, we present a multi-scale analytical model of the porous anode catalyst layers and individual catalyst agglomerates that enables determination of the effects of electrode morphology such as agglomerate size, catalyst loading, etc. on H2 transport resistance through the porous electrode to complement and better understand H2 limiting current experiments and deconvolute local H2 transport resistances.
Electrodes within PEMFCs are heterogeneous porous structures formed by agglomerates of carbon particles containing Pt nanoparticles, held together by an ion-conducting polymer (ionomer). The gas transport hence involves transport through multiple phases and length-scales: (i) gas-phase transport through electrode pores at the length scale of electrode thickness (micrometer) and (ii) diffusion into the agglomerate through an ionomer film at the length scale of agglomerate radius (nanometer). Based on previous modeling efforts of varying length-scales of the catalyst layer, our analytical model adequately and simultaneously captures reaction-diffusion at all of the aforementioned scales (i.e., the electrode thickness and agglomerate radius) to better describe porous anode performance. A sensitivity analysis is subsequently performed to compare current generated against transport parameters for both scales. This work ultimately provides insight that will guide the design and engineering of future porous anodes for applications in hydrogen pumping and PEMFCs.