Effect of nanocellulose polymorphism on electrochemical analytical performance in hybrid nanocomposites with non-oxidized single-walled carbon nanotubes

Abstract Two cellulose nanocrystals/single-walled carbon nanotube (CNC/SW) hybrids, using two cellulose polymorphs, were evaluated as electrochemical transducers: CNC type I (CNC-I/SW) and CNC type II (CNC-II/SW). They were synthesized and fully characterized, and their analytical performance as electrochemical sensors was carefully studied. In comparison with SWCNT-based and screen-printed carbon electrodes, CNC/SW sensors showed superior electroanalytical performance in terms of sensitivity and selectivity, not only in the detection of small metabolites (uric acid, dopamine, and tyrosine) but also in the detection of complex glycoproteins (alpha-1-acid glycoprotein (AGP)). More importantly, CNC-II/SW exhibited 20 times higher sensitivity than CNC-I/SW for AGP determination, yielding a LOD of 7 mg L−1.These results demonstrate the critical role played by nanocellulose polymorphism in the electrochemical performance of CNC/SW hybrid materials, opening new directions in the electrochemical sensing of these complex molecules. In general, these high-active-surface hybrids smartly exploited the preserved non-oxidized SW conductivity with the high aqueous dispersibility of the CNC, avoiding the use of organic solvents or the incorporation of toxic surfactants during their processing, making the CNC/SW hybrids promising nanomaterials for electrochemical detection following greener approaches. Graphical abstract

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Recent Advances in Electrochemical Sensors for the Detection of Biomolecules and Whole Cells

Biomedicines ◽

10.3390/biomedicines9010015 ◽

2020 ◽

Vol 9 (1) ◽

pp. 15

Author(s):

Intan Rosalina Suhito ◽

Kyeong-Mo Koo ◽

Tae-Hyung Kim

Keyword(s):

Electrochemical Sensors ◽

Metal Oxide Nanoparticles ◽

Electrochemical Sensing ◽

Critical Parameters ◽

Label Free ◽

Animal Cells ◽

Whole Cells ◽

Sensing Platforms ◽

Sensitivity And Selectivity ◽

Detection Of Biomolecules

Electrochemical sensors are considered an auspicious tool to detect biomolecules (e.g., DNA, proteins, and lipids), which are valuable sources for the early diagnosis of diseases and disorders. Advances in electrochemical sensing platforms have enabled the development of a new type of biosensor, enabling label-free, non-destructive detection of viability, function, and the genetic signature of whole cells. Numerous studies have attempted to enhance both the sensitivity and selectivity of electrochemical sensors, which are the most critical parameters for assessing sensor performance. Various nanomaterials, including metal nanoparticles, carbon nanotubes, graphene and its derivatives, and metal oxide nanoparticles, have been used to improve the electrical conductivity and electrocatalytic properties of working electrodes, increasing sensor sensitivity. Further modifications have been implemented to advance sensor platform selectivity and biocompatibility using biomaterials such as antibodies, aptamers, extracellular matrix (ECM) proteins, and peptide composites. This paper summarizes recent electrochemical sensors designed to detect target biomolecules and animal cells (cancer cells and stem cells). We hope that this review will inspire researchers to increase their efforts to accelerate biosensor progress—enabling a prosperous future in regenerative medicine and the biomedical industry.

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Protein adsorption to planar electrochemical sensors and sensor materials

Pure and Applied Chemistry ◽

10.1351/pac200476040753 ◽

2004 ◽

Vol 76 (4) ◽

pp. 753-763 ◽

Cited By ~ 15

Author(s):

Caroline Lim ◽

S. Slack ◽

S. Ufer ◽

E. Lindner

Keyword(s):

Protein Adsorption ◽

Electrochemical Sensors ◽

Surface Texturing ◽

Active Surface ◽

Electrochemical Sensing ◽

Dlc Coating ◽

Active Sensor ◽

Poly Ethylene ◽

Modified Sensor

In electrochemical sensing devices, aimed for acute and chronic in vivo application, the active surface of the sensor is often negligible compared to the overall surface area of the device in contact with the biological host. Consequently, to minimize the perturbation of an implanted sensor on the in vivo environment the chemical composition and surface texturing of the complete device (the active sensor, sensor substrate, and “accessories”) have to be considered. In our work, the adsorption of three abundant proteins (albumin, IgG, and fibrinogen) was determined quantitatively on untreated and modified sensor substrates and sensing membrane surfaces. In this study, a flexible polyimide-based material (Kapton ®) was used as sensor substrate with or without an amorphous diamond-like carbon (DLC) or an amorphous oxygen-containing DLC (o-DLC) coating. The ion-sensitive membranes were cast from high-molecular-weight (HMW) or carboxylated poly(vinyl chloride) (PVC) and were doped with increasing concentrations of highly hydrophilic poly(ethylene oxide) (PEO). The potentiometric characteristics of the potassium-selective membranes cast with up to 6 % PEO were the same as those without PEO. However, the PEO-modified PVC membranes elicited a large amount of protein adsorption, especially in terms of albumin.

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Nanomaterials in Electrochemical Sensing Area: Applications and Challenges in Food Analysis

Molecules ◽

10.3390/molecules25235759 ◽

2020 ◽

Vol 25 (23) ◽

pp. 5759

Author(s):

Antonella Curulli

Keyword(s):

Food Analysis ◽

Electrochemical Sensors ◽

Chemical Properties ◽

Electrochemical Sensing ◽

Morphological Properties ◽

Sensitivity And Selectivity ◽

Metallic Nanomaterials ◽

Application Fields ◽

Carbon Based Nanomaterials ◽

Physical And Chemical

Recently, nanomaterials have received increasing attention due to their unique physical and chemical properties, which make them of considerable interest for applications in many fields, such as biotechnology, optics, electronics, and catalysis. The development of nanomaterials has proven fundamental for the development of smart electrochemical sensors to be used in different application fields such, as biomedical, environmental, and food analysis. In fact, they showed high performances in terms of sensitivity and selectivity. In this report, we present a survey of the application of different nanomaterials and nanocomposites with tailored morphological properties as sensing platforms for food analysis. Particular attention has been devoted to the sensors developed with nanomaterials such as carbon-based nanomaterials, metallic nanomaterials, and related nanocomposites. Finally, several examples of sensors for the detection of some analytes present in food and beverages, such as some hydroxycinnamic acids (caffeic acid, chlorogenic acid, and rosmarinic acid), caffeine (CAF), ascorbic acid (AA), and nitrite are reported and evidenced.

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Recent Advances on Epidermal Growth Factor Receptor as a Molecular Target for Breast Cancer Therapeutics

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520621666201222143213 ◽

2020 ◽

Vol 21 ◽

Author(s):

Swathi R. Shetty ◽

Ragini Yeeravalli ◽

Tanya Bera ◽

Amitava Das

Keyword(s):

Breast Cancer ◽

Epidermal Growth Factor Receptor ◽

Growth Factor ◽

Epidermal Growth Factor ◽

Tyrosine Kinase ◽

Critical Role ◽

Growth Factor Receptor ◽

Type I ◽

Egfr Inhibition ◽

Epidermal Growth

: Epidermal growth factor receptor (EGFR), a type-I transmembrane protein with intrinsic tyrosine kinase activity is activated by peptide growth factors such as EGF, epigen, amphiregulin, etc. EGFR plays a vital role in regulating cell growth, migration, and differentiation in various tissue-specific cancers. It has been reported to be overexpressed in lung, head, and neck, colon, brain, pancreatic, and breast cancer that trigger tumor progression and drug resistance. EGFR overexpression alters the signaling pathway and induces cell division, invasion, and cell survival. Our prior studies demonstrated that EGFR inhibition modulates chemosensitivity in breast cancer stem cells thereby serving as a potential drug target for breast cancer mitigation. Tyrosine kinase inhibitors (Lapatinib, Neratinib) and monoclonal antibodies (Trastuzumab) targeting EGFR have been developed and approved by the US FDA for clinical use against breast cancer. This review highlights the critical role of EGFR in breast cancer progression and enumerates the various approaches being undertaken to inhibit aggressive breast cancers by suppressing the downstream pathways. Further, the mechanisms of action of potential molecules at various stages of drug development as well as clinically approved drugs for breast cancer treatment are illustrated.

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Collagen molecular phenotypic switch between non-neoplastic and neoplastic canine mammary tissues

Scientific Reports ◽

10.1038/s41598-021-87380-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Masahiko Terajima ◽

Yuki Taga ◽

Becky K. Brisson ◽

Amy C. Durham ◽

Kotaro Sato ◽

...

Keyword(s):

Breast Cancer ◽

Mammary Gland ◽

Mammary Carcinoma ◽

Cancer Biology ◽

Type I Collagen ◽

Critical Role ◽

Premature Death ◽

Mammary Tissue ◽

Type I ◽

Cross Links

AbstractIn spite of major advances over the past several decades in diagnosis and treatment, breast cancer remains a global cause of morbidity and premature death for both human and veterinary patients. Due to multiple shared clinicopathological features, dogs provide an excellent model of human breast cancer, thus, a comparative oncology approach may advance our understanding of breast cancer biology and improve patient outcomes. Despite an increasing awareness of the critical role of fibrillar collagens in breast cancer biology, tumor-permissive collagen features are still ill-defined. Here, we characterize the molecular and morphological phenotypes of type I collagen in canine mammary gland tumors. Canine mammary carcinoma samples contained longer collagen fibers as well as a greater population of wider fibers compared to non-neoplastic and adenoma samples. Furthermore, the total number of collagen cross-links enriched in the stable hydroxylysine-aldehyde derived cross-links was significantly increased in neoplastic mammary gland samples compared to non-neoplastic mammary gland tissue. The mass spectrometric analyses of type I collagen revealed that in malignant mammary tumor samples, lysine residues, in particular those in the telopeptides, were markedly over-hydroxylated in comparison to non-neoplastic mammary tissue. The extent of glycosylation of hydroxylysine residues was comparable among the groups. Consistent with these data, expression levels of genes encoding lysyl hydroxylase 2 (LH2) and its molecular chaperone FK506-binding protein 65 were both significantly increased in neoplastic samples. These alterations likely lead to an increase in the LH2-mediated stable collagen cross-links in mammary carcinoma that may promote tumor cell metastasis in these patients.

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Integrating high-performing electrochemical transducers in lateral flow assay

Analytical and Bioanalytical Chemistry ◽

10.1007/s00216-021-03301-y ◽

2021 ◽

Author(s):

Antonia Perju ◽

Nongnoot Wongkaew

Keyword(s):

High Performance ◽

Point Of Care ◽

Low Cost ◽

High Sensitivity ◽

Lateral Flow ◽

Analytical Performance ◽

Label Free ◽

High Performing ◽

Lateral Flow Assays ◽

Electrochemical Transducers

AbstractLateral flow assays (LFAs) are the best-performing and best-known point-of-care tests worldwide. Over the last decade, they have experienced an increasing interest by researchers towards improving their analytical performance while maintaining their robust assay platform. Commercially, visual and optical detection strategies dominate, but it is especially the research on integrating electrochemical (EC) approaches that may have a chance to significantly improve an LFA’s performance that is needed in order to detect analytes reliably at lower concentrations than currently possible. In fact, EC-LFAs offer advantages in terms of quantitative determination, low-cost, high sensitivity, and even simple, label-free strategies. Here, the various configurations of EC-LFAs published are summarized and critically evaluated. In short, most of them rely on applying conventional transducers, e.g., screen-printed electrode, to ensure reliability of the assay, and additional advances are afforded by the beneficial features of nanomaterials. It is predicted that these will be further implemented in EC-LFAs as high-performance transducers. Considering the low cost of point-of-care devices, it becomes even more important to also identify strategies that efficiently integrate nanomaterials into EC-LFAs in a high-throughput manner while maintaining their favorable analytical performance.

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Utilising Commercially Fabricated Printed Circuit Boards as an Electrochemical Biosensing Platform

Micromachines ◽

10.3390/mi12070793 ◽

2021 ◽

Vol 12 (7) ◽

pp. 793

Author(s):

Uroš Zupančič ◽

Joshua Rainbow ◽

Pedro Estrela ◽

Despina Moschou

Keyword(s):

Printed Circuit Boards ◽

Electrochemical Sensors ◽

Cost Effective ◽

Electrochemical Sensing ◽

Label Free ◽

Circuit Boards ◽

Printed Circuit ◽

Sensing Applications ◽

Electrochemical Biosensing ◽

Pre Treatment

Printed circuit boards (PCBs) offer a promising platform for the development of electronics-assisted biomedical diagnostic sensors and microsystems. The long-standing industrial basis offers distinctive advantages for cost-effective, reproducible, and easily integrated sample-in-answer-out diagnostic microsystems. Nonetheless, the commercial techniques used in the fabrication of PCBs produce various contaminants potentially degrading severely their stability and repeatability in electrochemical sensing applications. Herein, we analyse for the first time such critical technological considerations, allowing the exploitation of commercial PCB platforms as reliable electrochemical sensing platforms. The presented electrochemical and physical characterisation data reveal clear evidence of both organic and inorganic sensing electrode surface contaminants, which can be removed using various pre-cleaning techniques. We demonstrate that, following such pre-treatment rules, PCB-based electrodes can be reliably fabricated for sensitive electrochemical biosensors. Herein, we demonstrate the applicability of the methodology both for labelled protein (procalcitonin) and label-free nucleic acid (E. coli-specific DNA) biomarker quantification, with observed limits of detection (LoD) of 2 pM and 110 pM, respectively. The proposed optimisation of surface pre-treatment is critical in the development of robust and sensitive PCB-based electrochemical sensors for both clinical and environmental diagnostics and monitoring applications.

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Essential role of IPS-1 in innate immune responses against RNA viruses

Journal of Experimental Medicine ◽

10.1084/jem.20060792 ◽

2006 ◽

Vol 203 (7) ◽

pp. 1795-1803 ◽

Cited By ~ 345

Author(s):

Himanshu Kumar ◽

Taro Kawai ◽

Hiroki Kato ◽

Shintaro Sato ◽

Ken Takahashi ◽

...

Keyword(s):

Rna Viruses ◽

Rna Virus ◽

Critical Role ◽

Nuclear Factor Κb ◽

Type I ◽

Innate Immune Responses ◽

Antiviral Responses ◽

Deficient Mice

IFN-β promoter stimulator (IPS)-1 was recently identified as an adapter for retinoic acid–inducible gene I (RIG-I) and melanoma differentiation-associated gene 5 (Mda5), which recognize distinct RNA viruses. Here we show the critical role of IPS-1 in antiviral responses in vivo. IPS-1–deficient mice showed severe defects in both RIG-I– and Mda5-mediated induction of type I interferon and inflammatory cytokines and were susceptible to RNA virus infection. RNA virus–induced interferon regulatory factor-3 and nuclear factor κB activation was also impaired in IPS-1–deficient cells. IPS-1, however, was not essential for the responses to either DNA virus or double-stranded B-DNA. Thus, IPS-1 is the sole adapter in both RIG-I and Mda5 signaling that mediates effective responses against a variety of RNA viruses.

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Molecularly Imprinted Polymers Combined with Electrochemical Sensors for Food Contaminants Analysis

Molecules ◽

10.3390/molecules26154607 ◽

2021 ◽

Vol 26 (15) ◽

pp. 4607

Author(s):

Dounia Elfadil ◽

Abderrahman Lamaoui ◽

Flavio Della Pelle ◽

Aziz Amine ◽

Dario Compagnone

Keyword(s):

Food Safety ◽

Molecularly Imprinted Polymers ◽

Electrochemical Sensors ◽

Low Cost ◽

Electrochemical Analysis ◽

Ease Of Use ◽

Electrochemical Sensing ◽

Food Contaminants ◽

Molecularly Imprinted ◽

Imprinted Polymers

Detection of relevant contaminants using screening approaches is a key issue to ensure food safety and respect for the regulatory limits established. Electrochemical sensors present several advantages such as rapidity; ease of use; possibility of on-site analysis and low cost. The lack of selectivity for electrochemical sensors working in complex samples as food may be overcome by coupling them with molecularly imprinted polymers (MIPs). MIPs are synthetic materials that mimic biological receptors and are produced by the polymerization of functional monomers in presence of a target analyte. This paper critically reviews and discusses the recent progress in MIP-based electrochemical sensors for food safety. A brief introduction on MIPs and electrochemical sensors is given; followed by a discussion of the recent achievements for various MIPs-based electrochemical sensors for food contaminants analysis. Both electropolymerization and chemical synthesis of MIP-based electrochemical sensing are discussed as well as the relevant applications of MIPs used in sample preparation and then coupled to electrochemical analysis. Future perspectives and challenges have been eventually given.

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