Carbohydrate Biosensors

Jelinek, Raz; Kolusheva, Sofiya

doi:10.1021/cr0300284

Cited by 335 publications

(206 citation statements)

References 321 publications

Supporting

Mentioning

205

Contrasting

Unclassified

Order By: Relevance

“…Self-assembled monolayers (SAMs) have been extensively studied in recent years [1][2][3] due to their potential applications in various branches of surface technology, such as passivation, lubrication, surface engineering, development of (bio-)sensors 4 and biocompatibility. The self-assembly of alkanethiols on gold surfaces was the focus of many studies due to the model character of this system.…”

Section: Introductionmentioning

confidence: 99%

Adsorption kinetics of l-glutathione on gold and structural changes during self-assembly: an in situATR-IR and QCM study

Bieri

Bürgi

2006

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

The adsorption of L-glutathione (g-Glu-Cys-Gly) from ethanol on gold surfaces was studied in situ by both attenuated total reflection infrared (ATR-IR) spectroscopy and using a quartz crystal microbalance (QCM). The molecule is firmly anchored to the gold surface through the thiol group. Different IR signals of adsorbed L-glutathione, notably the amide I and n(-COOH), show significantly different behavior with time, which reveals that their increase is not related to adsorption (mass uptake) alone. This indicates that structural transformations take place during the formation of the self-assembled monolayer (SAM). In particular, the intensity of the acid signal increases quickly only within the first couple of minutes. The complexity of the selfassembling process is confirmed by QCM measurements, which show fast mass uptake within about 100 s followed by a considerably slower regime. The structural change superimposed on the mass uptake is, based on the in situ time-resolved ATR-IR measurements, assigned to the interaction of the acid group of the Gly moiety with the surface. The latter group is protonated in ethanol but deprotonates upon interaction with the gold surface. The protonation-deprotonation equilibrium is sensitive to external stimuli, such as the presence of dissolved L-glutathione molecules. The interaction of the acid group with the surface and concomitant deprotonation proceeds via two distinguishable steps, the first being a reorientation of the molecule, followed by the deprotonation.

show abstract

Section: Introductionmentioning

confidence: 99%

Adsorption kinetics of l-glutathione on gold and structural changes during self-assembly: an in situATR-IR and QCM study

Bieri

Bürgi

2006

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

show abstract

“…Carbohydrate-lectin interaction 9 is central in devising our biosensor. After mixing NPs with fluorescein-labeled Con A, a magnetic field was applied to the mixture through a handheld magnet inducing aggregation of magnetic NPs on the side of the vial.…”

mentioning

confidence: 99%

Magnetic Glyco-nanoparticles: A Unique Tool for Rapid Pathogen Detection, Decontamination, and Strain Differentiation

2007

View full text Add to dashboard Cite

The appealing mechanisms by which nanocomposites knit biomolecules not only lend credence in designing novel nanosensors but considerably advance medical applications. 1 Recent headline news about Escherichia coli (E. coli) contamination in produce and Bacillus anthracis attacks pinpoint the urgent need for an effective method for microbial decontamination and rapid detection without time-consuming cell culturing. It is known that many bacteria use mammalian cell surface carbohydrates as anchors for attachments, which subsequently results in infection. 2 The unique combination of magnetic nanocomposites and diverse carbohydrate bioactivities prompts us to embark on a biosensing research program. Herein, we report a magnetic glyco-nanoparticle (MGNP)-based system to not only detect E. coli within 5 min, but also remove up to 88% of the target bacteria from the medium. Furthermore, the identities of three different E. coli strains were easily determined on the basis of the response patterns to two MGNPs highlighting their potential in biosensing.It is advantageous to use magnetic nanoparticles (NPs) for detection. The high surface/volume ratio offers more contact surface area for attaching carbohydrates and for capturing pathogens. 3 The sizes of NPs are typically about 2 orders of magnitude smaller than a bacterium, which allows the attachment of multiple NPs onto a bacterial cell rendering easy magnet-mediated separation. 3,4 Moreover, the small NPs have faster kinetics in solution as compared to their micrometer-sized counterparts, which can result in fast detection.Our journey commenced with functionalization of silica-coated magnetite NP (NP 1) with D-mannose (Man) through either a triazole linker (MGNP 2) formed by the [2+3] Huisgen reaction 5 or an amide linkage (MGNP 3) (Schemes 1 and S1). With our covalent approach, 6 all carbohydrates are uniformly oriented on the NP surface, which is crucial for high performances in cell-capturing studies. 7 All MGNPs were characterized by X-ray diffraction, transmission electron microscopy (TEM), thermogravimetric analyses, and IR spectroscopy ( Figures S1-4).To ensure that carbohydrates on MGNP retain their binding abilities, the interaction between various MGNPs with a mannose binding lectin, concanavalin A (Con A), 8 was first investigated. Carbohydrate-lectin interaction 9 is central in devising our biosensor. After mixing NPs with fluorescein-labeled Con A, a magnetic field was applied to the mixture through a handheld magnet inducing aggregation of magnetic NPs on the side of the vial. The residual fluorescence of supernatants was then recorded ( Figure S5). With MGNP 3, the emission intensity of the supernatant decreased 87% indicating that most Con A was removed by 3. Triazole linked MGNP 2 was less efficient accounting for a 60% emission decrease probably because of the low efficiency of the Huisgen reaction with immobilized alkynes. 5 NP 1 without carbohydrates (control) did not remove any Con A, proving that the separation of Con A is due to its interaction...

show abstract

“…There have been extensive efforts to develop new devices suitable for routine measurement of heparin levels in clinical settings (1,23). Various approaches such as quartz crystal microbalance, surface plasmon resonance, ion-sensitive fieldeffect transistor, and membrane-based ion-selective electrode involve either protamine or synthetic cationic polymers as heparin probes, and they are based on either surface affinity capture or an automated heparin titration (23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34).…”

mentioning

confidence: 99%

Monitoring of heparin and its low-molecular-weight analogs by silicon field effect

Milović

Behr

Godin

et al. 2006

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Heparin is a highly sulfated glycosaminoglycan that is used as an important clinical anticoagulant. Monitoring and control of the heparin level in a patient's blood during and after surgery is essential, but current clinical methods are limited to indirect and off-line assays. We have developed a silicon field-effect sensor for direct detection of heparin by its intrinsic negative charge. The sensor consists of a simple microfabricated electrolyte-insulatorsilicon structure encapsulated within microfluidic channels. As heparin-specific surface probes the clinical heparin antagonist protamine or the physiological partner antithrombin III were used. The dose-response curves in 10% PBS revealed a detection limit of 0.001 units͞ml, which is orders of magnitude lower than clinically relevant concentrations. We also detected heparin-based drugs such as the low-molecular-weight heparin enoxaparin (Lovenox) and the synthetic pentasaccharide heparin analog fondaparinux (Arixtra), which cannot be monitored by the existing near-patient clinical methods. We demonstrated the specificity of the antithrombin III functionalized sensor for the physiologically active pentasaccharide sequence. As a validation, we showed correlation of our measurements to those from a colorimetric assay for heparin-mediated anti-Xa activity. These results demonstrate that silicon field-effect sensors could be used in the clinic for routine monitoring and maintenance of therapeutic levels of heparin and heparin-based drugs and in the laboratory for quantitation of total amount and specific epitopes of heparin and other glycosaminoglycans.heparin sensors ͉ label-free sensing ͉ medical devices ͉ enoxaparin ͉ fondaparinux

show abstract

Carbohydrate Biosensors

Cited by 335 publications

References 321 publications

Adsorption kinetics of l-glutathione on gold and structural changes during self-assembly: an in situATR-IR and QCM study

Adsorption kinetics of l-glutathione on gold and structural changes during self-assembly: an in situATR-IR and QCM study

Magnetic Glyco-nanoparticles: A Unique Tool for Rapid Pathogen Detection, Decontamination, and Strain Differentiation

Monitoring of heparin and its low-molecular-weight analogs by silicon field effect

Contact Info

Product

Resources

About