High percentages of harmful microbes or their secreting toxins bind to specific carbohydrate sequences on human cells at the recognition and attachment sites. A number studies also show that lectins react with structures bacteria fungi. In this report, we take advantage fact a high percentage microorganisms have both lectin binding pockets surface. We demonstrate here for first time nonlabeled mass sensor in combination lectin−bacterial O-antigen can be used detection molecular weight...

A Huisgen 1,3-dipolar cycloaddition "click chemistry" was employed to immobilize azido sugars (mannose, lactose, alpha-Gal) fabricate carbohydrate self-assembled monolayers (SAMs) on gold. This fabrication based preformed SAM templates incorporated with alkyne terminal groups, which could further anchor the form well-packed, stable, and rigid sugar SAMs. The clicked mannose, alpha-Gal trisaccharide SAMs were used in analysis of specific carbohydrate-protein interactions (i.e., mannose-Con A;...

Surface plasmon resonance (SPR) has become an important optical biosensing technology in the areas of biochemistry, biology, and medical sciences because its real-time, label-free, noninvasive nature. The high cost commercial devices consumables prevented SPR from being introduced undergraduate laboratory. Here we present affordable homemade device with all components accessible to visualization. This design allows ease integration electrochemistry makes suitable for education. We describe a...

Ionic liquids (ILs) exhibit complex behavior. Their simultaneous dual nature as solvents and electrolytes supports the existence of structurally tunable cations anions, which could provide basis a novel sensing technology. However, elucidation physiochemical properties ILs their connections with interaction redox mechanisms target analytes requires concerted data acquired from techniques including spectroscopic investigations, thermodynamic solvation models, molecular simulations. Our...

Bacterial separation from human blood samples can help with the identification of pathogenic bacteria for sepsis diagnosis. In this work, we report an acoustofluidic device label-free bacterial samples. particular, exploit acoustic radiation force generated a tilted-angle standing surface wave (taSSAW) field to separate E. coli cells based on their size difference. Flow cytometry analysis separated red (RBCs) shows purity more than 96%. Moreover, electrochemical detection displays reduced...

Fe doping in the NiS lattice leads to an increase density of states near Fermi level and thus improved charge storage.

A simple Clark-type online electrochemical cell design, consisting of a platinum gauze working electrode and incorporating ionic liquids (IL) as electrolytes, has been successfully applied for the amperometric sensing oxygen. Studying ILs comprising bis(trifluoromethylsulfonyl)imide anion, obtained analytical parameters were found to be strongly dependent on choice cation. Compared with conventional Clark design based an aqueous supporting electrolyte, modified oxygen sensor achieves...

Linking ionic liquid interface designs to specific device protocols address analytical challenges in gas sensing.

In this report, a new polythiophene interface is fabricated containing fused quinone moieties which are then glycosylated to form carbohydrate platform for bacterial detection. Very importantly, can be used label-free and reagentless detection, both by electrochemical Quartz Crystal Microbalance (QCM) transducers using the direct pili-mannose binding as well Concanavalin A (Con A) mediated lipopolysaccharides (LPS)-mannose binding. The conductive polymer's unique collective properties very...

In this work, we designed, fabricated, and characterized the first nitrogen (N)-doped single-crystalline 4H silicon carbide (4H-SiC) electrode for sensing neurotransmitter dopamine. This N-doped 4H-SiC showed good selectivity redox reactions of dopamine in comparison with uric acid (UA), ascorbic (AA), common cationic ([Ru(NH3)6]3+), anionic ([Fe(CN)6]3–), organic (methylene blue) molecules. The mechanisms unique are rationalized by negative Si valency adsorption properties analytes on...

A novel sensor array using seven room-temperature ionic liquids (ILs) as sensing materials and a quartz crystal microbalance (QCM) transducer was developed for the detection of organic vapors at ambient elevated temperatures. Ethanol, dichloromethane, benzene, heptane were selected representative gas analytes various kinds environmental pollutants common industrial solvents. The QCM/IL sensors responded proportionately reversibly to vapor concentrations (i.e., ethanol, heptane, benzene) in...

Using A10B single-chain fragment variable (scFv) as a model system, we demonstrated that the flexibility of scFv linker engineering can be combined with inherent quick and adaptable characters surface coupling chemistry (e.g., electrostatic, hydrogen bonding, or covalent attachment) to attach preformed functionalized self-assembled monolayers (SAMs). Six arginines, which were separated by glycine serine spacer, incorporated in peptide form 15-mer (RGRGRGRGRSRGGGS). The polycationic arginine...

Multichannel Monolithic Quartz Crystal Microbalance (MQCM), in which an array of electrodes is fabricated on a monolithic quartz wafer, very attractive approach for miniaturization using Micro-Electro-Mechanical Systems(MEMS) technology high throughput chemical or biological sensor systems. In this paper, we demonstrate and validate QCM gas detections. The chip was simple, straightforward method. Four pairs single AT-cut 10 MHz plate were both symmetric asymmetric designs. Their resonance...

Surface plasmon resonance (SPR) has been used in determining kinetics and thermodynamics of biological interaction the past decades. One difficulty encountered this technology is need for a proper regeneration, which means removal analytes from bound complexes to regenerate activity ligands. Regeneration not always practical since harsh regeneration reagents may destroy bioactivity It even more difficult with high affinity constants. In paper, we report nonregeneration protocol SPR...

We report the development of a new selective and specific electrochemical biosensor for bacterial lipolysaccharide (LPS). An electrode interface was constructed using l-cysteine-gold nanoparticle (AuNpCys) composite to be immobilized by electrostatic interaction in network poly(vinyl chloride-vinyl acetate maleic acid) (PVM) layer on gold bare electrode. The impedimetric is fabricated self-assembled CramoLL lectin PVM-AuNpCys-modified through interaction. used as recognition interface. AFM...

This paper introduces a robust electrochemical gas sensor featuring room temperature ionic liquid (RTIL) as electrolyte and porous polytetrafluoroethylene flexible substrate. Using planar-electrodes-on-permeable-membrane structure, RTIL with 9.6 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> sensing area is microfabricated. The sensor's response to oxygen measured, achieving sensitivity of 0.48 μA/%O <sub...

Current sensor devices for the detection of methane or natural gas emission are either expensive and have high power requirements fail to provide a rapid response.

ConspectusCarbohydrate–protein interactions occur through glycoproteins, glycolipids, or polysaccharides displayed on the cell surface with lectins. However, studying these is challenging because of complexity and heterogeneity surface, inherent structural carbohydrates, typically weak affinities binding reactions between lectins monovalent carbohydrates. The lack chromophores fluorophores in carbohydrate structures often drives such investigations toward fluorescence labeling techniques,...