Glycobiomimics and glycobiosensors

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.

Download Full-text

A Comprehensive Study on Aptasensors For Cancer Diagnosis

Current Pharmaceutical Biotechnology ◽

10.2174/1389201021999200918152721 ◽

2020 ◽

Vol 21 ◽

Author(s):

Sambhavi Animesh ◽

Yengkhom Disco Singh

Keyword(s):

Point Of Care ◽

High Specificity ◽

Molecular Probes ◽

Cancer Diagnostics ◽

New Class ◽

Point Of Care Diagnostics ◽

Efficient Detection ◽

Specificity And Sensitivity ◽

Highly Sensitive ◽

Cancer Tumor

: Cancer is the most devastating disease in the present scenario, killing millions of people every year. Early detection, accurate diagnosis, and timely treatment are considered to be the most effective ways to control this disease. Rapid and efficient detection of cancer at their earliest stage is one of the most significant challenges in cancer detection and cure. Numerous diagnostic modules have been developed to detect cancer cells early. As the nucleic acid is equivalent to antibodies, aptamers emerge as a new class of molecular probes that can identify cancer-related biomarkers or circulating rare cancer/tumor cells with very high specificity and sensitivity. The amalgamation of aptamers with the biosensing platforms gave birth to "Aptasensors." The advent of highly sensitive aptasensors has opened up many new promising point-of-care diagnostics for cancer. This comprehensive review focuses on the newly developed aptasensors for cancer diagnostics.

Download Full-text

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.

Download Full-text

A rapid and affordable point of care test for antibodies against SARS-CoV-2 based on hemagglutination and artificial intelligence interpretation

Scientific Reports ◽

10.1038/s41598-021-04298-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Vanessa Redecke ◽

Kazuki Tawaratsumida ◽

Erin T. Larragoite ◽

Elizabeth S. C. P. Williams ◽

Vicente Planelles ◽

...

Keyword(s):

Test Performance ◽

Learning Algorithm ◽

Point Of Care ◽

Method Comparison ◽

High Specificity ◽

Turnaround Time ◽

Analysis Tool ◽

Point Of Care Test ◽

Specificity And Sensitivity ◽

A Cell

AbstractDiagnostic tests that detect antibodies (AB) against SARS-CoV-2 for evaluation of seroprevalence and guidance of health care measures are important tools for managing the COVID-19 pandemic. Current tests have certain limitations with regard to turnaround time, costs and availability, particularly in point-of-care (POC) settings. We established a hemagglutination-based AB test that is based on bi-specific proteins which contain a dromedary-derived antibody (nanobody) binding red blood cells (RBD) and a SARS-CoV-2-derived antigen, such as the receptor-binding domain of the Spike protein (Spike-RBD). While the nanobody mediates swift binding to RBC, the antigen moiety directs instantaneous, visually apparent hemagglutination in the presence of SARS-CoV-2-specific AB generated in COVID-19 patients or vaccinated individuals. Method comparison studies with assays cleared by emergency use authorization demonstrate high specificity and sensitivity. To further increase objectivity of test interpretation, we developed an image analysis tool based on digital image acquisition (via a cell phone) and a machine learning algorithm based on defined sample-training and -validation datasets. Preliminary data, including a small clinical study, provides proof of principle for test performance in a POC setting. Together, the data support the interpretation that this AB test format, which we refer to as ‘NanoSpot.ai’, is suitable for POC testing, can be manufactured at very low costs and, based on its generic mode of action, can likely be adapted to a variety of other pathogens.

Download Full-text

A new lateral flow assay to detect sIL-2R during T-cell mediated rejection after kidney transplantation

The Analyst ◽

10.1039/d1an01001h ◽

2021 ◽

Author(s):

Lisa K. Seiler ◽

Rebecca Jonczyk ◽

Patrick Lindner ◽

Ncog Linh Phung ◽

Christine S. Falk ◽

...

Keyword(s):

Kidney Transplantation ◽

T Cell ◽

Point Of Care ◽

High Specificity ◽

Lateral Flow ◽

Lateral Flow Assay ◽

Point Of Care Test ◽

Specificity And Sensitivity ◽

Kidney Rejection ◽

Acute Kidney Rejection

In this work a novel point of care test to detect sIL-2R during acute kidney rejection with high specificity and sensitivity was developed.

Download Full-text

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.

Download Full-text

Antibodies and antibody-derived analytical biosensors

Essays in Biochemistry ◽

10.1042/ebc20150002 ◽

2016 ◽

Vol 60 (1) ◽

pp. 9-18 ◽

Cited By ~ 91

Author(s):

Shikha Sharma ◽

Hannah Byrne ◽

Richard J. O'Kennedy

Keyword(s):

Illicit Drugs ◽

Point Of Care ◽

High Specificity ◽

Biological Warfare ◽

Rapid Diagnostics ◽

Timely Initiation ◽

Specificity And Sensitivity ◽

Appropriate Treatment ◽

Biological Warfare Agents ◽

Warfare Agents

The rapid diagnosis of many diseases and timely initiation of appropriate treatment are critical determinants that promote optimal clinical outcomes and general public health. Biosensors are now being applied for rapid diagnostics due to their capacity for point-of-care use with minimum need for operator input. Antibody-based biosensors or immunosensors have revolutionized diagnostics for the detection of a plethora of analytes such as disease markers, food and environmental contaminants, biological warfare agents and illicit drugs. Antibodies are ideal biorecognition elements that provide sensors with high specificity and sensitivity. This review describes monoclonal and recombinant antibodies and different immobilization approaches crucial for antibody utilization in biosensors. Examples of applications of a variety of antibody-based sensor formats are also described.

Download Full-text

Glycoprotein- and Lectin-Based Approaches for Detection of Pathogens

Pathogens ◽

10.3390/pathogens9090694 ◽

2020 ◽

Vol 9 (9) ◽

pp. 694

Author(s):

Sammer-ul Hassan ◽

Ahmed Donia ◽

Usman Sial ◽

Xunli Zhang ◽

Habib Bokhari

Keyword(s):

Infectious Diseases ◽

Point Of Care ◽

Healthcare Providers ◽

Basic Research ◽

High Specificity ◽

Cost Effective ◽

Emerging Diseases ◽

Public Healthcare ◽

Point Of Use ◽

Specificity And Sensitivity

Infectious diseases alone are estimated to result in approximately 40% of the 50 million total annual deaths globally. The importance of basic research in the control of emerging and re-emerging diseases cannot be overemphasized. However, new nanotechnology-based methodologies exploiting unique surface-located glycoproteins or their patterns can be exploited to detect pathogens at the point of use or on-site with high specificity and sensitivity. These technologies will, therefore, affect our ability in the future to more accurately assess risk. The critical challenge is making these new methodologies cost-effective, as well as simple to use, for the diagnostics industry and public healthcare providers. Miniaturization of biochemical assays in lab-on-a-chip devices has emerged as a promising tool. Miniaturization has the potential to shape modern biotechnology and how point-of-care testing of infectious diseases will be performed by developing smart microdevices that require minute amounts of sample and reagents and are cost-effective, robust, and sensitive and specific. The current review provides a short overview of some of the futuristic approaches using simple molecular interactions between glycoproteins and glycoprotein-binding molecules for the efficient and rapid detection of various pathogens at the point of use, advancing the emerging field of glyconanodiagnostics.

Download Full-text

Multi-code magnetic beads based on DNAzyme-mediated double-cycling amplification for a point-of-care assay of telomerase activity

The Analyst ◽

10.1039/c9an00589g ◽

2019 ◽

Vol 144 (14) ◽

pp. 4241-4249 ◽

Cited By ~ 8

Author(s):

Chunxue Liu ◽

Susu Zhang ◽

Xia Li ◽

Qingwang Xue ◽

Wei Jiang

Keyword(s):

Medical Care ◽

Magnetic Beads ◽

Point Of Care ◽

High Specificity ◽

Telomerase Activity ◽

Activity Assay ◽

Double Cycling ◽

Specificity And Sensitivity ◽

Point Of Care Assay

Development of a reliable and facile telomerase activity assay with high specificity and sensitivity is a central challenge to make telomerase testing a routine part of medical care with respect to cancer.

Download Full-text

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

Scientific Reports ◽

10.1038/s41598-021-00057-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Indra Gandi Subramani ◽

Veeradasan Perumal ◽

Subash C. B. Gopinath ◽

Norani Muti Mohamed ◽

Mark Ovinis ◽

...

Keyword(s):

Bovine Milk ◽

High Specificity ◽

The Novel ◽

Label Free ◽

One Pot ◽

Inorganic Molecule ◽

Allergenic Protein ◽

Specificity And Sensitivity ◽

One Step ◽

Β Lactoglobulin

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.

Download Full-text

Leishmania infantum-Derived Glycoinositolphospholipids in the Immunodiagnosis of Subclinically Infected Dogs

Frontiers in Veterinary Science ◽

10.3389/fvets.2021.581148 ◽

2021 ◽

Vol 8 ◽

Author(s):

Julia Ramos Sampaio ◽

Rodrigo Pedro Soares ◽

Thiago Doria Barral ◽

Gabriela Porfirio Passos ◽

Maisa Santos Fonseca ◽

...

Keyword(s):

Leishmania Infantum ◽

Point Of Care ◽

High Specificity ◽

Storage Conditions ◽

Canine Leishmaniasis ◽

Lower Sensitivity ◽

Immune Recognition ◽

Specificity And Sensitivity ◽

Lower Specificity ◽

Very High

Lipophosphoglycan (LPG), when used as an ELISA target, confers high specificity and sensitivity to the detection of Leishmania infantum antibodies in dogs. Glycoconjugates are economically viable because the yield is very high after extraction/purification. In addition, they are very stable, which allows their use in point-of-care testing without special storage conditions. During the glycoconjugate extraction, a glycoinositolphospholipid (GIPL)-enriched fraction is obtained in similar quantities as LPG. Since GIPLs can be extracted from the same parasite pellet as LPGs, this work aimed to evaluate the immune recognition of GIPLs by Leishmania infantum-infected dogs and its use for canine leishmaniasis (CanL) immunodiagnosis. Like LPG, GIPLs were recognized by sera from L. infantum-infected dogs, but with less sensitivity (83.8%). However, 80% (16/20) of subclinically infected dogs were detected as positive in the assay. Different from LPG, the GIPL-based assay achieved a lower specificity (73.7%) and cross-reactions occurred with T. cruzi and L. braziliensis-infected dogs. Although GIPLs exhibited a similar performance to LPG for subclinically L. infantum-infected dogs, the occurrence of cross-reactivities with other protozoa and a lower sensitivity hinders its use for an immunodiagnostic test. In places where those diseases do not co-exist such as in the Mediterranean region, its use for subclinically dogs could be an alternative.

Download Full-text