Pillar[5]arene-Based Supramolecular Plasmonic Thin Films for Label-Free, Quantitative and Multiplex SERS Detection

AbstractCapacitive field-effect electrolyte-diamond-insulator-semiconductor (EDIS) structures with O-terminated nanocrystalline diamond (NCD) as sensitive gate material have been realized and investigated for the detection of pH, penicillin concentration, and layer-by-layer adsorption of polyelectrolytes. The surface oxidizing procedure of NCD thin films as well as the seeding and NCD growth process on a Si-SiO2 substrate have been improved to provide high pH-sensitive, non-porous thin films without damage of the underlying SiO2 layer and with a high coverage of O-terminated sites. The NCD surface topography, roughness, and coverage of the surface groups have been characterized by SEM, AFM and XPS methods. The EDIS sensors with O-terminated NCD film treated in oxidizing boiling mixture for 45 min show a pH sensitivity of about 50 mV/pH. The pH-sensitive properties of the NCD have been used to develop an EDIS-based penicillin biosensor with high sensitivity (65-70 mV/decade in the concentration range of 0.25-2.5 mM penicillin G) and low detection limit (5 μM). The results of label-free electrical detection of layer-by-layer adsorption of charged polyelectrolytes are presented, too.

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Label-free SERS detection of proteins based on machine learning classification of chemo-structural determinants

The Analyst ◽

10.1039/d0an02137g ◽

2021 ◽

Author(s):

Andrea Barucci ◽

Cristiano D'Andrea ◽

Edoardo Farnesi ◽

Martina Banchelli ◽

Chiara Amicucci ◽

...

Keyword(s):

Machine Learning ◽

Label Free ◽

Structural Determinants ◽

Machine Learning Classification ◽

Sers Detection ◽

Biological Differences

We implement a machine learning classification of similar proteins by PCA mixed with multipeak fitting on SERS spectra for effective discrimination based on valid biological differences.

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Application of Aluminum Hydroxide for Improvement of Label-Free SERS Detection of Some Cephalosporin Antibiotics in Urine

Biosensors ◽

10.3390/bios9030091 ◽

2019 ◽

Vol 9 (3) ◽

pp. 91 ◽

Cited By ~ 5

Author(s):

Natalia E. Markina ◽

Alexey V. Markin

Keyword(s):

Aluminum Hydroxide ◽

Surface Enhanced Raman Spectroscopy ◽

Negative Influence ◽

Quantitative Detection ◽

Therapeutic Drug ◽

Excitation Wavelength ◽

Sers Substrate ◽

Label Free ◽

Surface Enhanced Raman ◽

Sers Detection

This report is dedicated to development of surface-enhanced Raman spectroscopy (SERS) based analysis protocol for detection of antibiotics in urine. The key step of the protocol is the pretreatment of urine before the detection to minimize background signal. The pretreatment includes extraction of intrinsic urine components using aluminum hydroxide gel (AHG) and further pH adjusting of the purified sample. The protocol was tested by detection of a single antibiotic in artificially spiked samples of real urine. Five antibiotics of cephalosporin class (cefazolin, cefoperazone, cefotaxime, ceftriaxone, and cefuroxime) were used for testing. SERS measurements were performed using a portable Raman spectrometer with 638 nm excitation wavelength and silver nanoparticles as SERS substrate. The calibration curves of four antibiotics (cefuroxime is the exception) cover the concentrations required for detection in patient’s urine during therapy (25/100‒500 μg/mL). Random error of the analysis (RSD < 20%) and limits of quantification (20‒90 μg/mL) for these antibiotics demonstrate the applicability of the protocol for reliable quantitative detection during therapeutic drug monitoring. The detection of cefuroxime using the protocol is not sensitive enough, allowing only for qualitative detection. Additionally, time stability and batch-to-batch reproducibility of AHG were studied and negative influence of the pretreatment protocol and its limitations were estimated and discussed.

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Plasmonics for Biosensing

Materials ◽

10.3390/ma12091411 ◽

2019 ◽

Vol 12 (9) ◽

pp. 1411 ◽

Cited By ~ 15

Author(s):

Xue Han ◽

Kun Liu ◽

Changsen Sun

Keyword(s):

Thin Films ◽

Molecular Level ◽

Point Of Care ◽

High Sensitivity ◽

Short Review ◽

Dynamic Monitoring ◽

Label Free ◽

Plasmonic Resonance ◽

Hybrid Functions ◽

Resonance Modes

Techniques based on plasmonic resonance can provide label-free, signal enhanced, and real-time sensing means for bioparticles and bioprocesses at the molecular level. With the development in nanofabrication and material science, plasmonics based on synthesized nanoparticles and manufactured nano-patterns in thin films have been prosperously explored. In this short review, resonance modes, materials, and hybrid functions by simultaneously using electrical conductivity for plasmonic biosensing techniques are exclusively reviewed for designs containing nanovoids in thin films. This type of plasmonic biosensors provide prominent potential to achieve integrated lab-on-a-chip which is capable of transporting and detecting minute of multiple bio-analytes with extremely high sensitivity, selectivity, multi-channel and dynamic monitoring for the next generation of point-of-care devices.

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Label‐free superresolution effect of nonlinear reverse saturation absorption thin films through difference method

Journal of Microscopy ◽

10.1111/jmi.12838 ◽

2019 ◽

Vol 276 (2) ◽

pp. 82-88

Author(s):

C. DING ◽

J. WEI

Keyword(s):

Thin Films ◽

Difference Method ◽

Label Free ◽

Reverse Saturation Absorption ◽

Saturation Absorption

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A Review of Refractometric Sensors Based on Long Period Fibre Gratings

The Scientific World JOURNAL ◽

10.1155/2013/913418 ◽

2013 ◽

Vol 2013 ◽

pp. 1-14 ◽

Cited By ~ 45

Author(s):

G. Rego

Keyword(s):

Thin Films ◽

Refractive Index ◽

Transition Region ◽

Food Quality ◽

Scientific Community ◽

Surrounding Medium ◽

Quality And Safety ◽

Label Free ◽

Long Period ◽

Food Quality And Safety

In the last decade refractometric sensors have attracted an increasing interest by the scientific community due to their ability to perform ambient monitoring, to assess food quality and safety, and also to the fact that they enable the development of label free sensors in the biomedical area. These advances result, namely, from the use of long period fibre gratings in the turning points and/or with thin films in the transition region that allows resolutions of 10−6to changes in the refractive index of the surrounding medium. Resolutions exceeding 10−8can also be achieved when long period fibre gratings are combined with evanescent field based devices. This paper reviews the recent path towards the development of ultrahigh sensitive optical fibre refractometric sensors.

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A graphene oxide-gold nanostar hybrid based-paper biosensor for label-free SERS detection of serum bilirubin for diagnosis of jaundice

Biosensors and Bioelectronics ◽

10.1016/j.bios.2019.111713 ◽

2019 ◽

Vol 145 ◽

pp. 111713 ◽

Cited By ~ 13

Author(s):

Xiang Pan ◽

Linhu Li ◽

Hangduo Lin ◽

Jiayi Tan ◽

Haitao Wang ◽

...

Keyword(s):

Graphene Oxide ◽

Serum Bilirubin ◽

Label Free ◽

Sers Detection ◽

Gold Nanostar

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Lamellar nanoporous gold thin films with tunable porosity for ultrasensitive SERS detection in liquid and gas phase

Nanoscale ◽

10.1039/d0nr01721c ◽

2020 ◽

Vol 12 (23) ◽

pp. 12602-12612 ◽

Cited By ~ 1

Author(s):

Adrien Chauvin ◽

Marta Lafuente ◽

Jean Yves Mevellec ◽

Reyes Mallada ◽

Bernard Humbert ◽

...

Keyword(s):

Thin Films ◽

Gas Phase ◽

Chemical Etching ◽

Lamellar Structure ◽

Pure Copper ◽

Nanoporous Gold ◽

Pure Gold ◽

Trace Level ◽

Porous Gold ◽

Sers Detection

Porous gold lamellar structure with high SERS performance is created by copper chemical etching of a pure gold and pure copper stacked layers. SERS response is recorded for trace level detection of probe molecule in liquid and gas phase.

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