Source: UNIVERSITY OF MISSOURI submitted to
USE OF SERS METHODS TO IMPROVE FOOD SAFETY
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0233857
Grant No.
(N/A)
Project No.
MO-HAFE0011
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Jan 1, 2013
Project End Date
Dec 31, 2018
Grant Year
(N/A)
Project Director
Lin, ME.
Recipient Organization
UNIVERSITY OF MISSOURI
(N/A)
COLUMBIA,MO 65211
Performing Department
Food Systems & Bioengineering
Non Technical Summary
In summary, this project will focus on developing new detection methods in combination with the latest nanotechnology to improve food safety. Our results show that SERS and other nanotechnology-based methods are promising approaches to detect food contaminants. We expect that the outcomes this project will include new methodologies and novel, simple, rapid, and sensitive novel sensing techniques that can be used to greatly assist food safety regulators and the food industry to safeguard our food supply. These new methods will be used to monitor the contamination and adulteration of foods.
Animal Health Component
(N/A)
Research Effort Categories
Basic
(N/A)
Applied
(N/A)
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
71111221150100%
Goals / Objectives
Establish surface enhanced Raman spectroscopy (SERS) methods coupled with SERS-active substrates for detecting pesticides in foods; The objective of this study is to investigate the feasibility of using SERS coupled with gold substrates for rapid detection of pesticides in strawberries. Multivariate statistical analysis techniques such as partial least squares (PLS) and principal component analysis (PCA) will be used to analyze the SERS spectral data. Objective 2: Develop novel nanosubstrates, nanostructures, nanoparticles using inorganic materials (i.e. gold, silver, zinc oxide, titanium dioxide, etc) for food safety applications; Objective 3. Characterization and quantification of engineered nanoparticles in foods and investigate the fate, translocation, and behavior of nanomaterials and their toxicity.
Project Methods
Pesticides (captan, pyraclostrobin, and myclobutanil) were selected for this study. Organic strawberries were purchased from a local supermarket. Organic fruits were selected and cleaned to ensure that no pesticide residues existed on the samples. 100 ppm (w/v) of captan, pyraclostrobin, and myclobutanil stock solutions were prepared using a mixed solvent system (acetonitrile : H2O = 1 : 1, v/v). Solutions of 50, 10, 5, 1, 0.5, and 0.1 ppm pesticides were prepared by serial dilutions from the 100 ppm solution. The solvent without pesticides was used as the control.The strawberries were spiked with the corresponding volume of the working solution and extracted by 10 mL acetonitrile. A Renishaw RM1000 Raman Spectrometer System was used in SERS analysis. Klarite SERS-active substrates were used. SERS spectral data were analyzed by Delight software. Two multivariate statistical regression models, PLS and PCA, were constructed to predict analyte concentrations in tested samples. Please see the outline for more details.

Progress 01/01/13 to 12/31/18

Outputs
Target Audience: Audiences include food scientists, students, and professionals from academia, the food industry, and government. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?We provided training opportunities for four MS and five Ph.D. students who worked on this project. How have the results been disseminated to communities of interest?We have disseminated our results/data at the professional conferences including IFT, IAFP, and ACS. What do you plan to do during the next reporting period to accomplish the goals?We will continue to develop novel nanosubstrates, nanostructures, nanoparticles using organic and inorganic materials for food safety applications, and establish SERS methods coupled with novel nanosubstrates for detecting chemical contaminants in foods.

Impacts
What was accomplished under these goals? With growing concerns about food safety issues, there areincreasing demands on rapid and sensitive techniques that can detect prohibited substances in food products. This project established novel surface-enhanced Raman spectroscopy (SERS) methods coupled with simplified extraction protocol and SERS-active substrates to detect hazardous substances in food samples. Results demonstrate that SERS is a rapid and accurate method that can be used to monitor food safety. The outcomes of this project include a line of scientific articles, including: rapid determination of thiabendazole in juice bySERS coupled with novel gold nanosubstrates; facile synthesis of cellulose nanofiber nanocomposite as a SERS substrate for detection of thiram in juice; measurement of engineered nanoparticles in consumer products by SERS and neutron activation analysis; use of standing gold nanorods for detection of malachite green and crystal violet in fish by SERS; development of nanofibrillated cellulose coated with gold nanoparticles for measurement of melamine by SERS; using standing gold nanorod arrays as SERS substrates for detection of carbaryl residues in fruit juice and milk; cellulose nanofibers coated with silver nanoparticles as a SERS platform for detection of pesticides in apples; and other studies. All these results demonstrate that SERS coupled with various nanomaterials (gold, silver) is a rapid, sensitive, accurate, reliable, and non-destructive analytical technique to measure food quality and safety attributes.

Publications

  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Alsammarraie, A.K., Lin, M.*, Mustapha, A., Lin, H., Chen, X., Chen, Y., Wang, H., Huang, M. 2018. Rapid determination of thiabendazole in juice by SERS coupled with novel gold nanosubstrates. Food Chem. 259, 219-225.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Xiong, Z., Lin, M.*, Lin, H., Huang, M. 2018. Facile synthesis of cellulose nanofiber nanocomposite as a SERS substrate for detection of thiram in juice. Carbohydr. Polym. 189, 79-86.
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Chen, X., Nguyen, T., Gu, L., Lin, M.* 2017. Use of standing gold nanorods for detection of malachite green and crystal violet in fish by SERS. J. Food Sci. 82(7), 1640-1646.
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Xiong, Z., Chen, X., Liou, P., Lin, M.* 2017. Development of nanofibrillated cellulose coated with gold nanoparticles for measurement of melamine by SERS. Cellulose. 24, 2801-2811.
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Alsammarraie, F.K., Lin, M.* 2017. Using standing gold nanorod arrays as SERS substrates for detection of carbaryl residues in fruit juice and milk. J. Agric. Food Chem. 65(3), 666-674.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Liou, P., Nguyen, T., Lin, M.* 2018. Measurement of engineered nanoparticles in consumer products by surface-enhanced Raman spectroscopy and neutron activation analysis. J. Food Measurement Characterization. 12(2), 736-746.
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Liou, P., Nayigiziki, F. X., Kong, F., Mustapha, A., Lin, M.* 2017. Cellulose nanofibers coated with silver nanoparticles as a SERS platform for detection of pesticides in apples. Carbohydr. Polym. 157, 643-650.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Nguyen, T., Zhou, P., Mustapha, M., Lin, M.* 2016. Detection of silver nanoparticles in consumer products by surface-enhanced Raman spectroscopy. Analyst. 141, 5382-5389.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Kim, Y.J., Sun, X., Jones, J.E., Lin, M., Yu, Q., Li, H.* 2015. Surface modification of SERS substrates with plasma-polymerized trimethylsilane nanocoating. Appl. Surf. Sci. 331, 346-352.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Zhang, Z., Yu, Q., Li, H., Mustapha, A., Lin, M.* 2015. Standing gold nanorod arrays as reproducible SERS substrates for measurement of pesticides in apple juice and vegetables. J. Food Sci. 80(2), N450-458.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: 6/28/2017. Detection of Nanoparticles and Pesticides in Food and Consumer Products by Surface-Enhanced Raman Spectroscopy. 2017 IFT Annual Meeting. June 25-28, Las Vegas, NV.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Lin, M., Alsammarraie, F., Liou, P. Use of gold nanorod arrays and cellulose nanocomposite as SERS substrates for detection of pesticide residues in foods. 2017 TechConnect World Innovation Conference. May 14-17, 2017.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Lin, M. 2015. The Use of Standing gold nanorod arrays as reproducible SERS substrates for the detection of pesticides in foods. 2015 Institute of Biological Engineering (IBE) annual meeting. St. Louis, MO, March 5-7, 2015.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Nguyen, T. H.D.; Zhang, Z.; Mustapha, A.; Li H.; Lin, M. 2015. Use of graphene and gold nanorods as substrates for detection of pesticides by surface enhanced Raman spectroscopy. 2015 IFT Annual Meeting. Chicago, IL. July 11-14, 2015.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Nguyen, T., Zhang, Z., Mustapha, A., Li, H., Lin, M.* 2014. Use of graphene and gold nanorods as substrates for detection of pesticides by surface enhanced Raman spectroscopy. J. Agric. Food Chem. 62(43), 1044510451.


Progress 10/01/17 to 09/30/18

Outputs
Target Audience:Target audiences include food scientists, students, professionals from academia, the food industry, and the government. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?We provided training opportunities for two MS and two Ph.D. students who worked on this project. How have the results been disseminated to communities of interest?We have disseminated our results/data at the professional conferences including IFT, IAFP, and ACS.? What do you plan to do during the next reporting period to accomplish the goals?We will keep working on developing SERS methods coupled with nanosubstrates for detecting chemical contaminants in foods, and developing novel nanostructures using inorganic materials (gold and silver) for food safety applications.

Impacts
What was accomplished under these goals? In recent years, there have been increasing concerns about pesticide residues in various foods. On the other hand, there is growing attention in utilizing novel nanomaterials as highly sensitive, low-cost, and reproducible substrates for surface-enhanced Raman spectroscopy (SERS) applications.In the reporting period of time, ourstudy was to develop SERS method for rapid detection of pesticides that were extracted from different types of food samples (fruit juice and milk). A new SERS substrate was prepared by assembling gold nanorods into standing arrays on a gold-coated silicon slide. The standing nanorod arrays were neatly arranged, and were able to generate strong electromagnetic field in SERS measurement. The as-prepared SERS substrate was utilized to detect carbaryl in acetonitrile-water solution, fruits juice (orange and grapefruit), and milk. The results show that the concentrations of carbaryl spiked in fruit juice and milk were linearly correlated with the concentrations predicted by the partial least squares (PLS) models with r value of 0.91, 0.88, and 0.95 for orange juice, grapefruit juice, and milk, respectively. The SERS method was able to detect carbaryl that was extracted from fruits juice and milk samples at 50 ppb level. The detection limits of carbaryl were 509, 617, and 319 ppb in orange juice, grapefruit juice, and milk, respectively. All detection limits are below the Maximum Residue Limits that were set by the U.S. EPA. Moreover, satisfactory recoveries (82 to 97.5%) were accomplished for food samples using this method. These results demonstrate that SERS coupled with the standing gold nanorod array substrates is a rapid, reliable, sensitive, and reproducible method for the detection of pesticide residues infoods.

Publications

  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Alsammarraie, A.K., Lin, M.*, Mustapha, A., Lin, H., Chen, X., Chen, Y., Wang, H., Huang, M. 2018. Rapid determination of thiabendazole in juice by SERS coupled with novel gold nanosubstrates. Food Chem. 259, 219-225.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Xiong, Z., Lin, M.*, Lin, H., Huang, M. 2018. Facile synthesis of cellulose nanofiber nanocomposite as a SERS substrate for detection of thiram in juice. Carbohydr. Polym. 189, 79-86.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Liou, P., Nguyen, T., Lin, M.* 2018. Measurement of engineered nanoparticles in consumer products by surface-enhanced Raman spectroscopy and neutron activation analysis. J. Food Measurement Characterization. 12(2), 736-746.
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Chen, X., Nguyen, T., Gu, L., Lin, M.* 2017. Use of standing gold nanorods for detection of malachite green and crystal violet in fish by SERS. J. Food Sci. 82(7), 1640-1646.


Progress 10/01/16 to 09/30/17

Outputs
Target Audience:Audiences include food scientists, students, professionals from academia, the food industry, and government agencies. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?We provided training opportunities for two MS and two Ph.D. students who worked on this project. How have the results been disseminated to communities of interest?We have disseminated our results/data at the professional conferences including IFT, IAFP, and ACS. What do you plan to do during the next reporting period to accomplish the goals?We will continue to develop novel nanosubstrates, nanostructures, nanoparticles using organic and inorganic materials for food safety applications, and establish SERS methods coupled with novel nanosubstrates for detecting chemical contaminants in foods.

Impacts
What was accomplished under these goals? The outcomes of this project include a study aimed to develop a novel surface-enhanced Raman spectroscopy (SERS) method coupled with simplified extraction protocol and novel gold nanorod (AuNR) substrates to detect banned aquaculture substances (malachite green (MG) and crystal violet (CV)) and their mixture (1:1) in aqueous solution and fish samples. Multivariate statistical tools such as principal component analysis (PCA) and partial least squares regression (PLSR) were used in data analysis. PCA results demonstrate that SERS can distinguish MG, CV and their mixture (1:1) in aqueous solution and in fish samples. The detection limit of SERS coupled with standing AuNR substrates is 1 ppb for both MG and CV in fish samples. A good linear relationship between the actual concentration and predicted concentration of analytes based on PLSR models with R2 values from 0.87 to 0.99 were obtained, indicating satisfactory quantification results of this method. These results demonstrate that the SERS method coupled with AuNR substrates can be used for rapid and accurate detection of MG and CV in fish samples. With growing consumption of aquaculture products, there is increasing demand on rapid and sensitive techniques that can detect prohibited substances in the seafood products. This study established a novel SERS method coupled with simplified extraction protocol and AuNR substrates to detect banned substances (malachite green and crystal violet) in fish samples. SERS is a rapid and accurate method that can be used to monitor seafood safety.

Publications

  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Chen, X., Nguyen, T., Gu, L., Lin, M.* 2017. Use of standing gold nanorods for detection of malachite green and crystal violet in fish by SERS. J. Food Sci. 82(7), 1640-1646.
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Xiong, Z., Chen, X., Liou, P., Lin, M.* 2017. Development of nanofibrillated cellulose coated with gold nanoparticles for measurement of melamine by SERS. Cellulose. 24, 2801-2811.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Alsammarraie, F.K., Lin, M. Using standing gold nanorod arrays as SERS substrates for detection of carbaryl residues in fruit juice and milk. 2017 IFT Annual Meeting. June 25-28, Las Vegas, NV.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Lin, M., Alsammarraie, F., Liou, P. Use of gold nanorod arrays and cellulose nanocomposite as SERS substrates for detection of pesticide residues in foods. 2017 TechConnect World Innovation Conference. May 14-17, 2017.


Progress 10/01/15 to 09/30/16

Outputs
Target Audience:Audiences include food scientists, students, professionals from academia, the food industry, and government. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?We provided training opportunities for two MS and Ph.D. students who worked on this project. How have the results been disseminated to communities of interest?We have disseminated our results/data at the professional conferences including IFT, IAFP, and ACS. What do you plan to do during the next reporting period to accomplish the goals?We will continue to develop novel nanosubstrates, nanostructures, nanoparticles using organic and inorganic materials for food safety applications, and establish SERS methods coupled with novel nanosubstrates for detecting chemical contaminants in foods.

Impacts
What was accomplished under these goals? The outcomes of this project include using surface-enhanced Raman spectroscopy (SERS) for rapid detection and characterization of trace amounts of forchlorfenuron extracted from fruits. Forchlorfenuron is a plant growth regulator widely used in grapes and has negative effects on human health. In this study, gold-coated nanosubstrates were used for SERS measurements. Partial least squares (PLS) analysis was used as a statistical method for quantitative analysis of the spectral data. Our results demonstrate that enhanced Raman signals acquired from samples exhibited characteristic spectral patterns. The PLS results for quantification of forchlorfenuron were obtained: R = 0.96, RMSEP = 9.336×10-6. The detection limit for forchlorfenuron by SERS is 3.15 ppm for pure forchlorfenuron solutions and 4.43 ppm for forchlorfenuron extracted from grape skin. In addition, HPLC was also used to measure forchlorfenuron and verify SERS results. A good linear relationship was observed between 0 - 100 ppm with an R value of 0.999. These results demonstrate that SERS coupled with gold nanosubstrates is a rapid and simple method and it requires little sample preparation. It could be a practical approach to combine SERS with HPLC method to screen and analyze food samples for chemical contaminants and residues.

Publications

  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Zhang, Z., Yu, Q., Li, H., Mustapha, A., Lin, M. 2015. Standing gold nanorod arrays as reproducible SERS substrates for measurement of pesticides in apple juice and vegetables. J. Food Sci. 80(2), N450-458.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Kim, Y.J., Sun, X., Jones, J.E., Lin, M., Yu, Q., Li, H. 2015. Surface modification of SERS substrates with plasma-polymerized trimethylsilane nanocoating. Appl. Surf. Sci. 331, 346-352.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Qian, H., Lin, M., Zhou, P. 2016. Measurement of forchlorfenuron in grapes by surface-enhanced Raman spectroscopy coupled with gold nano substrates. Int. J. Food Sci. Nutr. Diet. 5(1), 258-264.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Nguyen, T. H.D.; Zhang, Z.; Mustapha, A.; Li H.; Lin, M. 2015. Use of graphene and gold nanorods as substrates for detection of pesticides by surface enhanced Raman spectroscopy. 2015 IFT Annual Meeting. Chicago, IL. July 11-14, 2015.


Progress 10/01/14 to 09/30/15

Outputs
Target Audience:Audiences include food scientists, students, professionals from academia, the food industry, and government. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?We provided training opportunities for several MS and Ph.D. students who worked on this project. How have the results been disseminated to communities of interest?We have disseminated our results/data at the professional conferences including IFT, IAFP, and ACS. What do you plan to do during the next reporting period to accomplish the goals?We will continue to establish SERS methods coupled with nanosubstrates for detecting chemical contaminants in foods, and to develop novel nanosubstrates, nanostructures, nanoparticles using inorganic materials (i.e. gold, silver) for food safety applications.

Impacts
What was accomplished under these goals? Our objective was focused on using novel nanomaterials as cost-effective, sensitive, and reproducible substrate for surface enhanced Raman spectroscopy (SERS) applications. In this study, a novel SERS substrate was developed by assembling gold nanorods into standing arrays on a gold-coated silicon slide. The standing nanorod arrays were closely packed on the gold film, generating strong electromagnetic field and uniformly distributed SERS "hot-spots" on the array surface. The as-prepared SERS substrates were used to detect a widely used pesticide (i.e. carbaryl) in acetonitrile-water solution,apple juice, and cabbage. Results demonstrate that the actual concentrations of carbaryl in apple juice and cabbage were linearly correlated with the concentrations predicted by the multiple linear regression models (R > 0.97). The detection limits of carbaryl in apple juice and cabbage were both 2.5 ppm, meeting the maximum residue limits built by US Environmental Protection Agency (EPA). SERS can detect as low as 0.1 ppm of carbaryl in acetonitrile-water solution. In addition, satisfactory recoveries were obtained for carbaryl in both apple juice and cabbage. These results indicate that SERS coupled with the standing gold nanorod array substrates is a sensitive and reproducible method and can accurately detect pesticides in foods.

Publications

  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Zhang, Z.; Yu, Q.; Li, H.; Mustapha, A.; Lin, M. 2015. Standing gold nanorod arrays as reproducible SERS substrates for measurement of pesticides in apple juice and vegetables. J. Food. Sci. 80(2), N450-458.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Al-Holy, M.A.; Lin, M.; Alhaj, Q.A.; Abu-Goush, M.H. 2015. Discrimination between Bacillus and Alicyclobacillus isolates in apple juice by Fourier transform infrared spectroscopy and multivariate statistical analysis. J. Food. Sci. 80(2), M309-404.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Nguyen, T.; Lin, M.*; Mustapha, A. 2015. Toxicity of graphene oxide on intestinal bacteria and Caco-2 Cells. J. Food. Prot. 78(5):996-1002.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Kim, Y.J.; Sun, X.; Jones, J.E.; Lin, M.; Yu, Q.; Li, H. 2015. Surface modification of SERS substrates with plasma-polymerized trimethylsilane nanocoating. Appl. Surf. Sci. 331, 346-352.


Progress 10/01/13 to 09/30/14

Outputs
Target Audience:Audiences were food scientists, students, professionals from academia, the food industry, and government agencies. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?This project provided training for two doctoral students and four Master's students. How have the results been disseminated to communities of interest?The results of this project have been disseminated in peer-reviewed journals, at the professional conferences including IFT and IAFP conferences. What do you plan to do during the next reporting period to accomplish the goals?During the next reporting period, we will continue tofabricate SERS-activesubstrates fordetection of food contaminants and environmental monitoring.

Impacts
What was accomplished under these goals? This study aimed to develop a rapid and simple method to functionalize gold nanorods by polyethylene glycol (PEG) that can be used for plasmonic sensing and SERS applications. PEG was successfully loaded on the CTAB-protected gold nanorods in 30 min using Tris buffer with pH of 3.0. On the contrary, the functionalization of gold nanorods in water induced the aggregation of gold nanorods and produced a floating layer of randomly aggregated nanorods at the water-air interface. The concentration of mPEG-SH has no significant influence on the optical property of gold nanorods modified by the proposed method. The result shows that the PEG-modified gold nanorods could sustain the 1.0 M of NaCl while CTAB-protected gold nanorods aggregated immediately after the addition of NaCl. Compared to a traditional 24-h method in CTAB/carbonate solution, the proposed method offers a higher loading speed and a higher coverage density of PEG on gold nanorods. It was also found that the PEG-modified NR-610 could form a very uniform monolayer on silicon upon the slow evaporation of water content. This method might open a new route to fabricate substrates for bio-medication, detection of food contaminants, and environmental monitoring.

Publications

  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Zhang, Z.; Lin, M. 2014. Fast loading of PEG-SH on CTAB-protected gold nanorod. RSC Adv. 4(34), 17760-17767.


Progress 01/01/13 to 09/30/13

Outputs
Target Audience: Audiences include food scientists, students, professionals from academia, the food industry, and government. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? We provided training opportunities for several MS and Ph.D. students who worked on this project. How have the results been disseminated to communities of interest? We have disseminated our results/data at the professional conferences including IFT, IAFP, and ACS. What do you plan to do during the next reporting period to accomplish the goals? We will continue to establish SERS methods coupled with nanosubstrates for detecting chemical contaminants in foods, and to develop novel nanosubstrates, nanostructures, nanoparticles using inorganic materials (i.e. gold, silver, zinc oxide, titanium dioxide, etc) for food safety applications.

Impacts
What was accomplished under these goals? During this reporting period, we conducted astudy about using surface-enhanced Raman spectroscopy (SERS) to detect herbicide residues (atrazine and arsenic trioxide) in drinking water. Gold-coated nanosubstrates were used in the SERS measurements to acquire enhanced Raman signals of herbicides in drinking water. Compared with the control, characteristic patterns of SERS spectra were distinguishable for atrazine at 3 ppb and arsenic trioxide at 1 ppb. Partial least squares (PLS) analysis was used to develop quantitative models for detection of two herbicides in drinking water and calibration curves were plotted with R2 of 0.988 and 0.991 for atrazine and arsenic trioxide, respectively. The study of limit of detection (LOD) demonstrates that at 99.86% confidence interval, SERS can detect both herbicides at 0.1 ppm in drinking water. Satisfactory recoveries were obtained for samples with concentration at and higher than the LOD (92.3 - 119.3% for atrazine and 88.2 - 102.1% for arsenic trioxide). These results demonstrate that SERS coupled with gold nanostructures holds great potential for rapid detection of herbicide residues and other chemical contaminants in drinking water.

Publications

  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Song, X., Li, H., Al-Qadiri, H. M., Lin, M. 2013. Detection of herbicides in drinking water by surface-enhanced Raman spectroscopy coupled with gold nanostructures. J. Food Measurement & Characterization 7(3), 107-113.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Zhang, Z., Zhang S., Lin, M. 2014. DNA-embedded Au-Ag core-shell nanoparticles assembled on silicon slides as a reliable SERS substrate. Analyst 139(9), 2207-2213.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Zhang, Z., Lin, M., Zhang, S., Vardhanabhuti, B. 2013. Detection of aflatoxin M1 in milk by dynamic light scattering coupled with superparamagnetic beads and gold nanoprobes. J. Agric. Food Chem. 61(19), 4520-4525.