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2D graphene-based advanced nanoarchitectonics for electrochemical biosensors: Applications in cancer biomarker detection
(ELSEVIER ADVANCED TECHNOLOGY, 2024-04-15) Mukherjee, Soumajit; Mukherjee, Atripan; Bytešníková, Zuzana; Ashrafi, Amirmansoor; Richtera, Lukáš; Adam, Vojtěch
Low-cost, rapid, and easy-to-use biosensors for various cancer biomarkers are of utmost importance in detecting cancer biomarkers for early-stage metastasis control and efficient diagnosis. The molecular complexity of cancer biomarkers is overwhelming, thus, the repeatability and reproducibility of measurements by biosensors are critical factors. Electrochemical biosensors are attractive alternatives in cancer diagnosis due to their low cost, simple operation, and promising analytical figures of merit. Recently graphene-derived nanostructures have been used extensively for the fabrication of electrochemical biosensors because of their unique physicochemical properties, including the high electrical conductivity, adsorption capacity, low cost and ease of mass production, presence of oxygen-containing functional groups that facilitate the bioreceptor immobilization, increased flexibility and mechanical strength, low cellular toxicity. Indeed, these properties make them advantageous compared to other alternatives. However, some drawbacks must be overcome to extend their use, such as poor and uncontrollable deposition on the substrate due to the low dispersity of some graphene materials and irreproducibility of the results because of the differences in various batches of the produced graphene materials. This review has documented the most recently developed strategies for electrochemical sensor fabrication. It differs in the categorization method compared to published works to draw greater attention to the wide opportunities of graphene nanomaterials for biological applications. Limitations and future scopes are discussed to advance the integration of novel technologies such as artificial intelligence, the internet of medical things, and triboelectric nanogenerators to eventually increase efficacy and efficiency.
Vertical organic electrochemical transistor platforms for efficient electropolymerization of thiophene based oligomers
(ROYAL SOC CHEMISTRY, 2024-04-18) Gryszel, Maciej; Byun, Donghak; Burtscher, Bernhard; Abrahamsson, Tobias; Brodský, Jan; Simon, Daniel Theodore; Berggren, Magnus; Glowacki, Eric Daniel; Strakosas, Xenofon; Donahue, Mary
Organic electrochemical transistors (OECTs) have emerged as promising candidates for various fields, including bioelectronics, neuromorphic computing, biosensors, and wearable electronics. OECTs operate in aqueous solutions, exhibit high amplification properties, and offer ion-to-electron signal transduction. The OECT channel consists of a conducting polymer, with PEDOT:PSS receiving the most attention to date. While PEDOT:PSS is highly conductive, and benefits from optimized protocols using secondary dopants and detergents, new p-type and n-type polymers are emerging with desirable material properties. Among these, low-oxidation potential oligomers are highly enabling for bioelectronics applications, however the polymers resulting from their polymerization lag far behind in conductivity compared with the established PEDOT:PSS. In this work we show that by careful design of the OECT geometrical characteristics, we can overcome this limitation and achieve devices that are on-par with transistors employing PEDOT:PSS. We demonstrate that the vertical architecture allows for facile electropolymerization of a family of trimers that are polymerized in very low oxidation potentials, without the need for harsh chemicals or secondary dopants. Vertical and planar OECTs are compared using various characterization methods. We show that vOECTs are superior platforms in general and propose that the vertical architecture can be expanded for the realization of OECTs for various applications. Vertical organic electrochemical transistor platforms enable facile channel formation by electropolymerization. The improved deposition control and resulting high performance is demonstrated here with the trimer ETE-COONa.
In Vivo Assessment on Freeze-Cast Calcium Phosphate-Based Scaffolds with a Selective Cell/Tissue Ingrowth
(AMER CHEMICAL SOC, 2024-10-21) Mařáková, Lucie; Pejchal, Jaroslav; Roleček, Jakub; Vojníková, Michaela; Chlup, Zdeněk; Mařák, Vojtěch; González-Sánchez, Manuela; Čížková, Jana; Salamon, David
Highly porous bioceramic scaffolds are widely used as bone substitutes in many applications. However, the use of bioceramics is often limited to hard tissues due to the risk of potential soft tissue calcification. A further limitation of highly porous bioceramic scaffolds is their poor mechanical stability, manifested by their tendency to break under stress. In our study, highly porous CaP-based scaffolds were prepared via freeze-casting with longitudinal and oriented pores ranging from 10 to 20 mu m and a relative porosity of similar to 70%. The resulting scaffolds achieved a flexural strength of 10.6 +/- 2.7 MPa, which, in conjunction with their favorable bioactivity, made them suitable for in vivo testing. The prepared scaffolds were subcutaneously implanted in rats for two distinct periods: 6 weeks and 6 months, respectively. The subsequent development of fibrous tissue and involvement of myofibroblasts, newly formed vessels, and macrophages were observed, with notable changes in spatial and temporal distributions within the implantation. The absence of calcification in the surrounding soft tissue, as a result of the narrow pore geometry, indicates the opportunity to tailor the scaffold behavior for soft tissue regeneration.
The impact of single and combined amendment of elemental sulphur and graphene oxide on soil microbiome and nutrient transformation activities
(Elsevier Ltd, 2024-10-15) Hammerschmiedt, Tereza; Holátko, Jiří; Bytešníková, Zuzana; Škarpa, Petr; Richtera, Lukáš; Kintl, Antonín; Pekárková, Jana; Kučerík, Jiří; Jaskulska, Iwona; Radziemska, Maja; Valová, Radmila; Malíček, Ondřej; Brtnický, Martin
Background: Sulphur (S) deficiency has emerged in recent years in European soils due to the decreased occurrence of acid rains. Elemental sulphur (S0) is highly beneficial as a source of S in agriculture, but it must be oxidized to a plant-accessible form. Micro- or nano-formulated S0 may undergo accelerated transformation, as the oxidation rate of S0 indirectly depends on particle size. Graphene oxide (GO) is a 2D-carbon-based nanomaterial with benefits as soil amendment, which could modulate the processes of S0 oxidation. Micro-and nano-sized composites, comprised of S0 and GO, were tested as soil amendments in a pot experiment with unplanted soil to assess their effects on soil microbial biomass, activity, and transformation to sulphates. Fourteen different variants were tested, based on solely added GO, solely added micro- or nano-sized S0 (each in three different doses) and on a combination of all S0 doses with GO. Results: Compared to unamended soil, nano-S0 and nano-S0+GO increased soil pH(CaCl2). Micro-S0 (at a dose 4 g kg1) increased soil pH(CaCl2), whereas micro-S0+GO (at a dose 4 g kg1) decreased soil pH(CaCl2). The total bacterial and ammonium oxidizer microbial abundance decreased due to micro-S0 and nano-S0 amendment, with an indirect dependence on the amended dose. This trend was alleviated by the co-application of GO. Urease activity showed a distinct response to micro-S0+GO (decreased value) and nano-S0+GO amendment (increased value). Arylsulfatase was enhanced by micro-S0+GO, while sulphur reducing bacteria (dsr) increased proliferation due to high micro-S0 and nano-S0, and co-amendment of both with GO. In comparison to nano-S0, the amendment of micro-S0+GO more increased soluble sulphur content more significantly. Conclusions: Under the conditions of this soil experiment, graphene oxide exhibited a significant effect on the process of sulphur oxidation.
Exploring the Frontiers of Cell Temperature Measurement and Thermogenesis
(WILEY, 2024-10-28) Zhu, Hanliang; Xu, Haotian; Zhang, Yue; Brodský, Jan; Gablech, Imrich; Korabečná, Marie; Neužil, Pavel
The precise measurement of cell temperature and an in-depth understanding of thermogenic processes are critical in unraveling the complexities of cellular metabolism and its implications for health and disease. This review focuses on the mechanisms of local temperature generation within cells and the array of methods developed for accurate temperature assessment. The contact and noncontact techniques are introduced, including infrared thermography, fluorescence thermometry, and other innovative approaches to localized temperature measurement. The role of thermogenesis in cellular metabolism, highlighting the integral function of temperature regulation in cellular processes, environmental adaptation, and the implications of thermogenic dysregulation in diseases such as metabolic disorders and cancer are further discussed. The challenges and limitations in this field are critically analyzed while technological advancements and future directions are proposed to overcome these barriers. This review aims to provide a consolidated resource for current methodologies, stimulate discussion on the limitations and challenges, and inspire future innovations in the study of cellular thermodynamics.

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