Four-Cantilever Trace Explosive Sensors with Dual SAMs Functionalized for Specific-Sensing Improvement and Nonspecific-Adsorption Depression

Clickable Cellulosic Surfaces for Peptide-Based Bioassays

10.26434/chemrxiv.8109143.v1 ◽

2019 ◽

Author(s):

Maria Teresa Odinolfi ◽

Alessandro Romanato ◽

Greta Bergamaschi ◽

Alessandro Strada ◽

Laura Sola ◽

...

Keyword(s):

Target Recognition ◽

Real Case ◽

Polymeric Coating ◽

Healthy Controls ◽

Nonspecific Adsorption ◽

Cellulosic Materials ◽

Cellulose Substrates

The use of peptides in paper-based analytics is a highly appealing field, yet it suffers from severe limitations. This is mostly due to the loss of effective target recognition properties of this relatively small bioprobes upon nonspecific adsorption onto cellulose substrates. Here, we address this issue by introducing a simple polymer-based strategy to obtain clickable cellulosic surfaces, that we exploited for the chemoselective bioconjugation of peptide bioprobes. Our method largely outperformed standard adsorption-based immobilization strategy in a challenging, real-case immunoassay, namely the diagnostic discrimination of Zika+ individuals from healthy controls. Of note, the clickable polymeric coating not only allows efficient peptides bioconjugation, but it provides favorable anti-fouling properties to the cellulosic support. We envisage our strategy to broaden the repertoire of cellulosic materials manipulation and promote a renewed interest in peptide-based paper bioassays.

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Clickable Cellulosic Surfaces for Peptide-Based Bioassays

10.26434/chemrxiv.8109143 ◽

2019 ◽

Author(s):

Maria Teresa Odinolfi ◽

Alessandro Romanato ◽

Greta Bergamaschi ◽

Alessandro Strada ◽

Laura Sola ◽

...

Keyword(s):

Target Recognition ◽

Real Case ◽

Polymeric Coating ◽

Healthy Controls ◽

Nonspecific Adsorption ◽

Cellulosic Materials ◽

Cellulose Substrates

The use of peptides in paper-based analytics is a highly appealing field, yet it suffers from severe limitations. This is mostly due to the loss of effective target recognition properties of this relatively small bioprobes upon nonspecific adsorption onto cellulose substrates. Here, we address this issue by introducing a simple polymer-based strategy to obtain clickable cellulosic surfaces, that we exploited for the chemoselective bioconjugation of peptide bioprobes. Our method largely outperformed standard adsorption-based immobilization strategy in a challenging, real-case immunoassay, namely the diagnostic discrimination of Zika+ individuals from healthy controls. Of note, the clickable polymeric coating not only allows efficient peptides bioconjugation, but it provides favorable anti-fouling properties to the cellulosic support. We envisage our strategy to broaden the repertoire of cellulosic materials manipulation and promote a renewed interest in peptide-based paper bioassays.

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Improving Surface Imprinting Effect by Reducing Nonspecific Adsorption on Non-imprinted Polymer Films for 2,4-D Herbicide Sensors

Chemosensors ◽

10.3390/chemosensors9030043 ◽

2021 ◽

Vol 9 (3) ◽

pp. 43

Author(s):

Jin Chul Yang ◽

Suck Won Hong ◽

Jinyoung Park

Keyword(s):

Morphological Changes ◽

Unit Weight ◽

Dichlorophenoxyacetic Acid ◽

Surface Imprinting ◽

Imprinted Polymer ◽

Nonspecific Adsorption ◽

Chemical Surface ◽

Silane Modification ◽

Silanized Silica ◽

2,4 Dichlorophenoxyacetic Acid

Surface imprinting used for template recognition in nanocavities can be controlled and improved by surface morphological changes. Generally, the lithographic technique is used for surface patterning concerning sensing signal amplification in molecularly imprinted polymer (MIP) thin films. In this paper, we describe the effects of silanized silica molds on sensing the properties of MIP films. Porous imprinted poly(MAA–co–EGDMA) films were lithographically fabricated using silanized or non-treated normal silica replica molds to detect 2,4-dichlorophenoxyacetic acid (2,4-D) herbicide as the standard template. The silanized mold MIP film (st-MIP) (Δf = −1021 Hz) exhibited a better sensing response than the non-treated normal MIP (n-MIP) (Δf = −978 Hz) because the imprinting effects, which occurred via functional groups on the silica surface, could be reduced through silane modification. Particularly, two non-imprinted (NIP) films (st-NIP and n-NIP) exhibited significantly different sensing responses. The st-NIP (Δfst-NIP = −332 Hz) films exhibited lower Δf values than the n-NIP film (Δfn-NIP = −610 Hz) owing to the remarkably reduced functionality against nonspecific adsorption. This phenomenon led to different imprinting factor (IF) values for the two MIP films (IFst-MIP = 3.38 and IFn-MIP = 1.86), which was calculated from the adsorbed 2,4-D mass per poly(MAA–co–EGDMA) unit weight (i.e., QMIP/QNIP). Moreover, it was found that the st-MIP film had better selectivity than the n-MIP film based on the sensing response of analogous herbicide solutions. As a result, it was revealed that the patterned molds’ chemical surface modification, which controls the surface functionality of imprinted films during photopolymerization, plays a role in fabricating enhanced sensing properties in patterned MIP films.

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Eliminating Nonspecific Binding Sites for Highly Reliable Immunoassay via Super-resolution Multicolor Fluorescence Colocalization

Nanoscale ◽

10.1039/d0nr08103e ◽

2021 ◽

Author(s):

Shenfei Zong ◽

Yun Liu ◽

Kuo Yang ◽

Zhaoyan Yang ◽

Zhuyuan Wang ◽

...

Keyword(s):

Binding Sites ◽

Super Resolution ◽

Specific Adsorption ◽

Nonspecific Binding ◽

Nonspecific Adsorption ◽

Multicolor Fluorescence

Non-specific adsorption in immunoassays has always been a major problem that affects the reliability of assay results. Despite the emergence of various methods which can reduce nonspecific adsorption, a universal...

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Immobilization and nonspecific adsorption of proteins to pyrogeneous highly dispersed silicon dioxide

Biotechnology Letters ◽

10.1007/bf01026661 ◽

1987 ◽

Vol 9 (8) ◽

pp. 561-566 ◽

Cited By ~ 8

Author(s):

M. Fusek ◽

M. Čapka ◽

J. Turková

Keyword(s):

Silicon Dioxide ◽

Nonspecific Adsorption ◽

Highly Dispersed

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Flexible Graphene Sensors for Explosive Trace Detection

Volume 11: Nano and Micro Materials, Devices and Systems; Microsystems Integration ◽

10.1115/imece2011-64135 ◽

2011 ◽

Author(s):

Je Kyun Lee ◽

Steven Green ◽

Sangyup Song ◽

Paul Phamduy ◽

Byungki Kim

Keyword(s):

Graphene Oxide ◽

Polyethylene Terephthalate ◽

Oxide Coating ◽

Trace Detection ◽

Closed Container ◽

Explosive Sensors

This paper presents an explosives sensor. The sensor consists of graphene spray coated onto a substrate with electrodes patterned on the surface. The substrates included glass and flexible polyethylene terephthalate (PET), and the leads were gold and silver respectively. Testing utilizing dinitrotoulene 2,4 (DNT) in a closed container showed the validity of using glass/gold based substrate with a graphene oxide coating as explosive sensors.

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