Wafer-Scale and Cost-Effective Manufacturing of Controllable Nanogap Arrays for Highly Sensitive SERS Sensing

Safety and quality are key issues for the food industry. Consequently, there is growing demand to preserve the food chain and products against substances toxic, harmful to human health, such as contaminants, allergens, toxins, or pathogens. For this reason, it is mandatory to develop highly sensitive, reliable, rapid, and cost-effective sensing systems/devices, such as electrochemical sensors/biosensors. Generally, conventional techniques are limited by long analyses, expensive and complex procedures, and skilled personnel. Therefore, developing performant electrochemical biosensors can significantly support the screening of food chains and products. Here, we report some of the recent developments in this area and analyze the contributions produced by electrochemical biosensors in food screening and their challenges.

Download Full-text

Computerized color perimetry in multiple sclerosis

Multiple Sclerosis Journal ◽

10.1177/135245859800400207 ◽

1998 ◽

Vol 4 (2) ◽

pp. 79-84 ◽

Cited By ~ 6

Author(s):

N Accornero ◽

S Rinalduzzi ◽

M Capozza ◽

E Millefiorini ◽

G C Filligoi ◽

...

Keyword(s):

Visual Field ◽

Statistical Difference ◽

Cost Effective ◽

Quantitative Information ◽

Field Analysis ◽

Visual Field Defects ◽

Highly Sensitive ◽

The Subject ◽

Color Perimetry ◽

Field Defects

Color visual field analysis has proven highly sensitive for early visual impairments diagnosis in MS, yet it has never attained widespread popularity usually because the procedure is difficult to standardize, the devices are costly, and the test is fatiguing. We propose a computerized procedure running on standard PC, cost effective, clonable, and easy handled. Two hundred and sixty-four colored patches subtending 18 angle of vision, with selected hues and low saturation levels are sequentially and randomly displayed on gray equiluminous background of the PC screen subtending 2486408 angle of vision. The subject is requested to press a switch at the perception of the stimulus. The output provides colored maps with quantitative information. Comparison between normals and a selected population of MS patients with no actual luminance visual field defects, showed high statistical difference.

Download Full-text

Improved Refractive Index Sensitivity Utilizing Long-Period Gratings with Periodic Corrugations on Cladding

Journal of Sensors ◽

10.1155/2012/483471 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5 ◽

Cited By ~ 12

Author(s):

Anthony Lim ◽

Wen Bin Ji ◽

Swee Chuan Tjin

Keyword(s):

Refractive Index ◽

Cost Effective ◽

Experimental Results ◽

Refractive Index Sensitivity ◽

Long Period ◽

Specimen Collection ◽

Long Period Gratings ◽

Highly Sensitive ◽

Index Sensitivity

A new structure of Long-Period Gratings (LPGs) sensor is introduced as a sensitive ambient RI sensor. This structure consists of creating periodic corrugations on the cladding of the LPG. The experimental results show that this LPG structure has good performances in terms of linearity and sensitivity and serves as a highly sensitive and cost-effective sensor. It also has the advantage of portability as the corrugation can also serve as the reservoir for the specimen collection to be tested.

Download Full-text

Development of a highly sensitive and selective spectrophotometric method for the determination of carvedilol in pharmaceutical and urine samples

RSC Advances ◽

10.1039/c4ra06526c ◽

2014 ◽

Vol 4 (77) ◽

pp. 40816-40823

Author(s):

Masoud Shariati-Rad ◽

Mohsen Irandoust ◽

Sara Sheikhi

Keyword(s):

Spectrophotometric Method ◽

Cost Effective ◽

Urine Samples ◽

Highly Sensitive

A simple, sensitive, selective, accurate and cost-effective spectrophotometric method for the determination of CAR in pharmaceutical and urine samples was developed.

Download Full-text

Highly sensitive and cost-effective fluorescent turn-on sensors based on octamethylcalix[4]pyrrole receptor for the detection of fluoride anion

Dyes and Pigments ◽

10.1016/j.dyepig.2021.109918 ◽

2021 ◽

pp. 109918

Author(s):

Sana Amharar ◽

Abdullah Aydogan

Keyword(s):

Cost Effective ◽

Fluoride Anion ◽

Turn On ◽

Highly Sensitive

Download Full-text

Saline collection media and an extraction free workflow enables massively scalable, highly sensitive, and cost-effective SARS-CoV-2 testing

10.21203/rs.3.rs-106189/v1 ◽

2020 ◽

Author(s):

Yan Wei Lim ◽

Nicole Leonetti ◽

Aakash Amin ◽

Henrique Machado ◽

Natasha Bonilla ◽

...

Keyword(s):

Supply Chain ◽

Sensitivity And Specificity ◽

Limit Of Detection ◽

Rna Extraction ◽

Cost Effective ◽

Scaling Up ◽

Consumption Patterns ◽

Highly Sensitive ◽

Processing Steps

Abstract The challenges in scaling up SARS-CoV-2 testing capacity include shortages in the supply chain for consumables and reagents. Improvements in consumption patterns can be obtained through removal of key processing steps, including RNA extraction. Here, we present a scalable and validated extraction-free method for the detection of SARS-CoV-2 from swab specimens in saline, with a limit of detection at 1,000 GCE/mL and a sensitivity and specificity of 100%.

Download Full-text

The Modified Telephone-Administered Minnesota Cognitive Acuity Screen for Mild Cognitive Impairment

Journal of Geriatric Psychiatry and Neurology ◽

10.1177/0891988718776131 ◽

2018 ◽

Vol 31 (3) ◽

pp. 123-128 ◽

Cited By ~ 2

Author(s):

Sarah Pillemer ◽

George D. Papandonatos ◽

Cara Crook ◽

Brian R. Ott ◽

Geoffrey Tremont

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Characteristic Curve ◽

Neuropsychological Testing ◽

Cost Effective ◽

Original Version ◽

Modest Improvement ◽

Highly Sensitive ◽

Risk Of Progression ◽

Administration Time

Objective: This study aimed to compare the sensitivity and specificity of a modified version of the Minnesota Cognitive Acuity Screen (MCAS-m), by adding learning and recognition memory components, to the original version MCAS to distinguish amnestic mild cognitive impairment (aMCI) from healthy controls (HCs). Methods/Design: A total of 30 individuals with aMCI and 30 HCs underwent neuropsychological testing, neurologic examination, laboratory, and brain imaging tests. Once diagnosis was confirmed, participants completed the MCAS and MCAS-m in counterbalanced order. Results: The average administration time was 12.6 minutes for the MCAS and 13.5 minutes for the MCAS-m. Receiver operating characteristic curve analyses showed that the MCAS-m demonstrated 97% sensitivity and 97% specificity for distinguishing between aMCI and HC versus 97% and 87%, respectively, for the original MCAS in this sample. Conclusions: Both the MCAS and the MCAS-m were highly sensitive when distinguishing between normal cognition and aMCI; however, the MCAS-m demonstrated a 10% increase in specificity compared to the original version. Improved specificity is particularly relevant to screening in larger community samples with lower base rates of MCI than clinic populations. This modified screening measure presents a brief and cost-effective tool for identifying MCI. Given the risk of progression from aMCI to Alzheimer disease dementia (AD), the MCAS-m represents a modest improvement in telephone-administered methods for the early detection of AD.

Download Full-text

Ultrasensitive surface-enhanced Raman scattering detection of urea by highly ordered Au/Cu hybrid nanostructure arrays

Chemical Communications ◽

10.1039/c7cc03523c ◽

2017 ◽

Vol 53 (56) ◽

pp. 7949-7952 ◽

Cited By ~ 9

Author(s):

Kun Chen ◽

Xinyi Zhang ◽

Douglas R. MacFarlane

Keyword(s):

Raman Scattering ◽

Cost Effective ◽

Surface Enhanced Raman Scattering ◽

Simple Approach ◽

Hybrid Nanostructure ◽

Highly Sensitive ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Nanostructure Arrays ◽

Enhanced Raman Scattering

We report a simple approach to fabricate cost-effective and highly sensitive surface-enhanced Raman scattering substrates based on Au/Cu hybrid nanostructure arrays for the detection of urea, an important molecule in biological and medical fields.

Download Full-text

Simple, Fast, and Cost-Effective Fabrication of Wafer-Scale Nanohole Arrays on Silicon for Antireflection

Journal of Nanomaterials ◽

10.1155/2014/439212 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 4

Author(s):

Di Di ◽

Xuezhong Wu ◽

Peitao Dong ◽

Chaoguang Wang ◽

Jian Chen ◽

...

Keyword(s):

High Throughput ◽

Crystalline Silicon ◽

Colloidal Crystal ◽

Cost Effective ◽

Wafer Scale ◽

Crystalline Silicon Solar Cells ◽

Cost Effective Method ◽

Nanohole Arrays ◽

Coating Method ◽

Hole Arrays

A simple, fast, and cost-effective method was developed in this paper for the high-throughput fabrication of nanohole arrays on silicon (Si), which is utilized for antireflection. Wafer-scale polystyrene (PS) monolayer colloidal crystal was developed as templates by spin-coating method. Metallic shadow mask was prepared by lifting off the oxygen etched PS beads from the deposited chromium film. Nanohole arrays were fabricated by Si dry etching. A series of nanohole arrays were fabricated with the similar diameter but with different depth. It is found that the maximum depth of the Si-hole was determined by the diameter of the Cr-mask. The antireflection ability of these Si-hole arrays was investigated. The results show that the reflection decreases with the depth of the Si-hole. The deepest Si-hole arrays show the best antireflection ability (reflection < 9%) at long wavelengths (>600 nm), which was about 28 percent of the nonpatterned silicon wafer’s reflection. The proposed method has the potential for high-throughput fabrication of patterned Si wafer, and the low reflectivity allows the application of these wafers in crystalline silicon solar cells.

Download Full-text