1,1'-Carbonyldiimidazole-copper nanoflower enhanced collapsible laser scribed graphene engraved microgap capacitive aptasensor for the detection of milk allergen

AbstractThe bovine milk allergenic protein, ‘β-lactoglobulin’ is one of the leading causes of milk allergic reaction. In this research, a novel label-free non-faradaic capacitive aptasensor was designed to detect β-lactoglobulin using a Laser Scribed Graphene (LSG) electrode. The graphene was directly engraved into a microgapped (~ 95 µm) capacitor-electrode pattern on a flexible polyimide (PI) film via a simple one-step CO2 laser irradiation. The novel hybrid nanoflower (NF) was synthesized using 1,1′-carbonyldiimidazole (CDI) as the organic molecule and copper (Cu) as the inorganic molecule via one-pot biomineralization by tuning the reaction time and concentration. NF was fixed on the pre-modified PI film at the triangular junction of the LSG microgap specifically for bio-capturing β-lactoglobulin. The fine-tuned CDI-Cu NF revealed the flower-like structures was viewed through field emission scanning electron microscopy. Fourier-transform infrared spectroscopy showed the interactions with PI film, CDI-Cu NF, oligoaptamer and β-lactoglobulin. The non-faradaic sensing of milk allergen β-lactoglobulin corresponds to a higher loading of oligoaptamer on 3D-structured CDI-Cu NF, with a linear range detection from 1 ag/ml to 100 fg/ml and attomolar (1 ag/ml) detection limit (S/N = 3:1). This novel CDI-Cu NF/LSG microgap aptasensor has a great potential for the detection of milk allergen with high-specificity and sensitivity.

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Highly Sensitive Fluorescent Detection of Acetylcholine Based on the Enhanced Peroxidase-Like Activity of Histidine Coated Magnetic Nanoparticles

Nanomaterials ◽

10.3390/nano11051207 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1207

Author(s):

Hong Jae Cheon ◽

Quynh Huong Nguyen ◽

Moon Il Kim

Keyword(s):

Magnetic Nanoparticles ◽

High Sensitivity ◽

High Specificity ◽

Choline Oxidase ◽

Fluorescent Detection ◽

One Pot ◽

Site Structure ◽

Specificity And Sensitivity ◽

Highly Sensitive ◽

Peroxidase Mimics

Inspired by the active site structure of natural horseradish peroxidase having iron as a pivotal element with coordinated histidine residues, we have developed histidine coated magnetic nanoparticles (His@MNPs) with relatively uniform and small sizes (less than 10 nm) through one-pot heat treatment. In comparison to pristine MNPs and other amino acid coated MNPs, His@MNPs exhibited a considerably enhanced peroxidase-imitating activity, approaching 10-fold higher in catalytic reactions. With the high activity, His@MNPs then were exploited to detect the important neurotransmitter acetylcholine. By coupling choline oxidase and acetylcholine esterase with His@MNPs as peroxidase mimics, target choline and acetylcholine were successfully detected via fluorescent mode with high specificity and sensitivity with the limits of detection down to 200 and 100 nM, respectively. The diagnostic capability of the method is demonstrated by analyzing acetylcholine in human blood serum. This study thus demonstrates the potential of utilizing His@MNPs as peroxidase-mimicking nanozymes for detecting important biological and clinical targets with high sensitivity and reliability.

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The pCS20 PCR assay for Ehrlichia ruminantium does not cross-react with the novel deer ehrlichial agent found in white-tailed deer in the United States of America

Onderstepoort Journal of Veterinary Research ◽

10.4102/ojvr.v71i2.271 ◽

2004 ◽

Vol 71 (2) ◽

Cited By ~ 4

Author(s):

S.M. Mahan ◽

B.H. Simbi ◽

M.J. Burridge

Keyword(s):

United States ◽

High Specificity ◽

Pcr Primers ◽

The United States ◽

Rrna Gene ◽

The Novel ◽

Pcr Assay ◽

Ehrlichia Ruminantium ◽

Cowdria Ruminantium ◽

Specificity And Sensitivity

White-tailed deer are susceptible to heartwater (Ehrlichia [Cowdria] ruminantium infection) and are likely to suffer high mortality if the disease spreads to the United States. It is vital, therefore, to validate a highly specific and sensitive detection method for E. ruminantium infection that can be reliably used in testing white-tailed deer, which are reservoirs of antigenically or genetically related agents such as Ehrlichia chaffeensis, Anaplasma (Ehrlichia) phagocytophilum (HGE agent) and Ehrlichia ewingii. Recently, a novel but as yet unnamed ehrlichial species, the white-tailed deer ehrlichia (WTDE), has been discovered in deer populations in the United States. Although the significance of WTDE as a pathogen is unknown at present, it can be distinguished from other Ehrlichia spp. based on 16S rRNA gene sequence analysis. In this study it was differentiated from E. ruminantium by the use of the pCS20 PCR assay which has high specificity and sensitivity for the detection of E. ruminantium. This assay did not amplify DNA from the WTDE DNA samples isolated from deer resident in Florida, Georgia and Missouri, but amplified the specific 279 bp fragment from E. ruminantium DNA. The specificity of the pCS20 PCR assay for E. ruminantium was confirmed by Southern hybridization. Similarly, the 16S PCR primers (nested) that amplify a specific 405-412 bp fragment from the WTDE DNA samples, did not amplify any product from E. ruminantium DNA. This result demonstrates that it would be possible to differentiate between E. ruminantium and the novel WTDE agent found in white tailed deer by applying the two respective PCR assays followed by Southern hybridizations. Since the pCS20 PCR assay also does not amplify any DNA products from E. chaffeensis or Ehrlichia canis DNA, it is therefore the method of choice for the detection of E. ruminantium in these deer and other animal hosts.

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Competitive SNP-LAMP probes for rapid and robust single-nucleotide polymorphism detection

10.1101/2021.03.29.437576 ◽

2021 ◽

Author(s):

Leland B Hyman ◽

Clare R Christopher ◽

Philip A Romero

Keyword(s):

Point Of Care ◽

High Specificity ◽

Common Source ◽

Lamp Method ◽

Universal Method ◽

Nucleotide Polymorphisms ◽

One Pot ◽

Single Nucleotide ◽

Specificity And Sensitivity ◽

And Shifts

Single-nucleotide polymorphisms (SNPs) are the most common source of genetic variation between individuals and have implications in human disease, pathogen drug resistance, and agriculture. SNPs are typically detected using DNA sequencing, which requires advanced sample preparation and instrumentation, and thus cannot be deployed for on-site testing or in low-resource settings. In this work we have developed a simple and robust assay to rapidly detect SNPs in nucleic acid samples. Our approach combines LAMP-based target amplification with fluorescent probes to detect SNPs with high specificity in a one-pot reaction format. A competitive "sink" strand preferentially binds to off-target products and shifts the free energy landscape to favor specific activation by SNP products. We demonstrated the broad utility and reliability of our SNP-LAMP method by detecting three distinct SNPs across the human genome. We also designed an assay to rapidly detect highly transmissible SARS-CoV-2 variants. This work demonstrates that competitive SNP-LAMP is a powerful and universal method that could be applied in point-of-care settings to detect any target SNP with high specificity and sensitivity.

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Immunochemiluminescence in the diagnosis of relapsing froms of echinococcosis

Kazan medical journal ◽

10.17750/kmj2017-141 ◽

2017 ◽

Vol 98 (1) ◽

pp. 141-143

Author(s):

N B Kasyev ◽

M S Aytnazarov ◽

A A Kazieva ◽

A N Nurbekova

Keyword(s):

Lung Cancer ◽

Diagnostic Method ◽

High Specificity ◽

The Novel ◽

Disease Relapse ◽

Serologic Test ◽

Specificity And Sensitivity ◽

Time Period ◽

Short Time ◽

Chemiluminescent Method

Aim. To improve immunologic diagnosis of relapsing and residual echinococcosis we used the novel chemiluminescent method based on registration of changes of biologic fluids emmision in normal and pathologic conditions.Methods. We observed 136 patients with relapsing echinococcosis, 109 patients with primary echinococcosis and 91 patients with residual cavities after echinococcectomy. As a control we included 186 patients with other diseases such as hepatitis, liver cirrhosis, liver and lung cancer, cholecystitis and others having some clinical similarity with echinococcosis and requiring differential diagnosis, and also 30 donors were included. Besides, 111 people previously operated for echinococcosis (6 month to 10 years prior) were examined.Results. In comparison of immunochemiluminescence with well-known serologic test this method demonstrated some benefits: short time to receiving the results, small amount of the blood necessary for the analysis (0.02 ml), high specificity and sensitivity. As the time period after the surgery increases, intensity of luminescence in immunochemiluminescence gradually decreases in case of no relapse and increases in relapse.Conclusion. Immunochemiluminescence of the whole blood is a valuable diagnostic method; this method should be included to diagnostic workup for patients with suspected echinococcosis; immunochemiluminescence provides the opportunity to define pathology and radicality of performed surgery and to reveal the disease relapse.

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Thrombin Assessment on Nanostructured Label-Free Aptamer-Based Sensors: A Mapping Investigation via Surface-Enhanced Raman Spectroscopy

BioMed Research International ◽

10.1155/2018/5293672 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Elisa Scatena ◽

Sara Pascale ◽

Cristina Cairone ◽

Filippo Fabbri ◽

Costantino Del Gaudio

Keyword(s):

Raman Spectroscopy ◽

Ad Hoc ◽

High Specificity ◽

Surface Enhanced Raman Spectroscopy ◽

Label Free ◽

Rna Molecules ◽

Specificity And Sensitivity ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Aptamer Sensor

Aptamers, synthetic single-stranded DNA or RNA molecules, can be regarded as a valuable improvement to develop novel ad hoc sensors to diagnose several clinical pathologies. Their intrinsic potential is related to the high specificity and sensitivity to the selected target biomarkers, being capable of detecting very low concentrations and thus allowing an early diagnosis of a possible disease. This kind of probe can be usefully integrated into a number of different devices in order to provide a reliable acquisition of the analyte and properly elaborate the related signal. The study presents the fabrication and characterization of a label-free aptamer sensor designed using a gold-coated silicon nanostructured substrate to map the target molecule by means of surface-enhanced Raman spectroscopy (SERS). As a proof, thrombin was used as a model at four different concentrations (i.e., 0.0873, 0.873, 8.73, and 87.3 nM). SERS mapping analysis was carried out considering each representative band of the aptamer-thrombin complex (centered at 822, 1140, and 1558 cm−1) and then combining them in order to acquire a comprehensive and unambiguous measure of the target. In both cases, a valuable correlation was evaluated, even if the first approach can suffer from some limitations in the third band related to lower definition of the characteristic peak compared to those in the other two bands.

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Glycobiomimics and glycobiosensors

Biochemical Society Transactions ◽

10.1042/bst0381333 ◽

2010 ◽

Vol 38 (5) ◽

pp. 1333-1336 ◽

Cited By ~ 24

Author(s):

Jared Q. Gerlach ◽

Stephen Cunningham ◽

Marian Kane ◽

Lokesh Joshi

Keyword(s):

Point Of Care ◽

Chinese Hamster ◽

High Specificity ◽

Science Research ◽

Label Free ◽

New Class ◽

Specificity And Sensitivity ◽

Development And Differentiation ◽

Low Levels ◽

Cancer And Inflammation

Following steady advances in analytical technologies, our knowledge in glycomics is now increasing rapidly. Over the last decade, specific glycans have been described that are associated with a range of diseases, such as cancer and inflammation, with host–pathogen interactions and with various stages during stem cell development and differentiation. Simultaneously, deeper structural insight has been gained on glycosylated biopharmaceutical protein therapeutics manufactured in CHO (Chinese-hamster ovary) and other cell systems. This glycomic information is highly relevant for clinicians and biomanufacturing industries as a new class of glycobiomarkers emerges. However, current methods of glycoanalysis are primarily research tools and are not suitable for point-of-care on-site detection and analysis, or sensor devices. Lectin-based glycan detection provides the most promising approach to fill these gaps. However, the limited availability of lectins with high specificity and sensitivity for specific glycan motifs presents one of the main challenges in building reliable glycobiosensors. Recent reports have demonstrated the use of recombinant protein engineering, phage display and aptamer technologies in the production of lectin mimics, as well as the construction of biosensors that are capable of rapidly detecting glycan motifs at low levels in both a labelled and label-free manner. These are primarily proof-of-principle reports at this stage, but some of the approaches, either alone or in combination, will lead to functional glycobiosensors in the coming years which will be valuable tools for the clinical, biopharmaceutical and life science research communities.

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Graphene-Based Hall Effect Biosensor for Improved Specificity and Sensitivity of Label-Free DNA Detection

NANO ◽

10.1142/s1793292020500885 ◽

2020 ◽

Vol 15 (07) ◽

pp. 2050088

Author(s):

Naiyuan Cui ◽

Fei Wang ◽

Hanyuan Ding

Keyword(s):

Hall Effect ◽

Dna Hybridization ◽

Chemical Vapor ◽

High Specificity ◽

Label Free ◽

Complementary Dna ◽

Mismatched Dna ◽

Specificity And Sensitivity ◽

Label Free Detection ◽

Detection Of Biomolecules

There is a broad interest in using graphene or graphene oxide (GO) sheets as a transducer for selective and label-free detection of biomolecules such as DNA, tumor marker, biological ions, etc. Here, a chemical vapor deposition (CVD) graphene-based Hall effect biosensor used for ultrasensitive label-free detection of DNA via DNA hybridization is reported. Hall effect measurements based on the Van der Pauw method are used to perform single-base sequence selective detection of DNA on graphene sheets, which are prepared by CVD. The mobility decreases and the sheet resistance increases with the adding of either complementary or one-base mismatched DNA to the graphene device. The hole carrier concentration of the graphene devices increases apparently with the addition of complementary DNA while it is hardly affected by the one-base mismatched DNA. The detection limit as low as 1[Formula: see text]pM was realized with a linear range from 1[Formula: see text]pM to 100[Formula: see text]nM. Moreover, the Hall effect biosensor was able to distinguish the complementary DNA from one-base mismatched DNA with a high specificity of [Formula: see text]6.2 which is almost two orders of magnitude higher than that of the previously reported graphene biosensors based on DNA–DNA hybridization.

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One-pot synthesis of novel water-dispersible fluorescent silicon nanoparticles for selective Cr2O72− sensing

Analytical Methods ◽

10.1039/d0ay01977a ◽

2021 ◽

Author(s):

Qiaoqiao Wen ◽

Congjie Pan ◽

Xuezhen Qin ◽

Qiujuan Ma ◽

Suxiang Feng

Keyword(s):

Hydrothermal Method ◽

Silicon Nanoparticles ◽

Visual Detection ◽

The Novel ◽

One Pot ◽

Water Dispersible ◽

Fluorescent Silicon Nanoparticles ◽

One Step ◽

Filtering Effect ◽

Paper Sensor

The novel water dispersible SiNPs which were prepared by a one-step hydrothermal method were applied to the detection of Cr2O72−via internal filtering effect (IFE) and a fluorescent paper sensor for visual detection of Cr2O72− was developed.

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A Study on the Rearrangement of Dialkyl 1-Aryl-1-hydroxymethylphosphonates to Benzyl Phosphates

Current Organic Chemistry ◽

10.2174/1385272824666200226114306 ◽

2020 ◽

Vol 24 (4) ◽

pp. 465-471 ◽

Cited By ~ 2

Author(s):

Zita Rádai ◽

Réka Szabó ◽

Áron Szigetvári ◽

Nóra Zsuzsa Kiss ◽

Zoltán Mucsi ◽

...

Keyword(s):

Quantum Chemical ◽

Room Temperature ◽

Phase Transfer ◽

One Pot ◽

Substrate Dependence ◽

Triethylbenzylammonium Chloride ◽

One Step ◽

The Pudovik Reaction ◽

The One ◽

Solid Liquid

The phospha-Brook rearrangement of dialkyl 1-aryl-1-hydroxymethylphosphonates (HPs) to the corresponding benzyl phosphates (BPs) has been elaborated under solid-liquid phase transfer catalytic conditions. The best procedure involved the use of triethylbenzylammonium chloride as the catalyst and Cs2CO3 as the base in acetonitrile as the solvent at room temperature. The substrate dependence of the rearrangement has been studied, and the mechanism of the transformation under discussion was explored by quantum chemical calculations. The key intermediate is an oxaphosphirane. The one-pot version starting with the Pudovik reaction has also been developed. The conditions of this tandem transformation were the same, as those for the one-step HP→BP conversion.

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Recent Advances on Therapeutic Peptides for Breast Cancer Treatment

Current Protein and Peptide Science ◽

10.2174/1389203721999201117123616 ◽

2020 ◽

Vol 21 ◽

Author(s):

Samad Beheshtirouy ◽

Farhad Mirzaei ◽

Shirin Eyvazi ◽

Vahideh Tarhriz

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Tumor Cells ◽

Breast Cancer Cells ◽

Specific Binding ◽

High Specificity ◽

The Novel ◽

Anti Cancer ◽

Therapeutic Peptides ◽

Low Toxicity

: Breast cancer is a heterogeneous malignancy which is the second cause of mortality among women in the world. Increasing the resistance to anti-cancer drugs in breast cancer cells persuades researchers to search the novel therapies approaches for the treatment of the malignancy. Among the novel methods, therapeutic peptides which target and disrupt tumor cells have been of great interest. Therapeutic peptides are short amino acids monomer chains with high specificity to bind and modulate a protein interaction of interest. Several advantages of peptides such as specific binding on tumor cells surface, low molecular weight and low toxicity on normal cells make the peptides as an appealing therapeutic agents against solid tumors, particularly breast cancer. Also, National Institutes of Health (NIH) describes therapeutic peptides as suitable candidate for the treatment of drug-resistant breast cancer. In this review, we attempt to review the different therapeutic peptides against breast cancer cells which can be used in treatment and diagnosis of the malignancy. Meanwhile, we presented an overview of peptide vaccines which have been developed for the treatment of breast cancer.

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