Advancing Mycotoxin Detection: Multivariate Rapid Analysis on Corn Using Surface Enhanced Raman Spectroscopy (SERS).

Mycotoxin contamination on food and feed can have deleterious effect on human and animal health. Agricultural crops may contain one or more mycotoxin compounds; therefore, a good multiplex detection method is desirable to ensure food safety. In this study, we developed a rapid method using label-free surface-enhanced Raman spectroscopy (SERS) to simultaneously detect three common types of mycotoxins found on corn, namely aflatoxin B1 (AFB1), zearalenone (ZEN), and ochratoxin A (OTA).

Rapid concentration detection and differentiation of bacteria in skimmed milk using surface enhanced Raman scattering mapping on 4-mercaptophenylboronic acid functionalized silver dendrites.

A novel method was developed to rapidly concentrate, detect, and differentiate bacteria in skimmed milk using surface enhanced Raman scattering (SERS) mapping on 4-mercaptophenylboronic acid (4-MPBA) functionalized silver (Ag) dendrites. The 4-MPBA functionalized Ag dendritic SERS substrate was used to capture the bacterial cells and enhance the bacterial signal. Salmonella, a significantly important food pathogen, was used as the representative strain to optimize and evaluate the developed method.

Aptamer-Based SERS Detection of Lysozyme on a Food-Handling Surface.

Undeclared food allergens due to cross contamination of processing equipment is a leading cause for food product recalls. Therefore, there is a great need for developing rapid and sensitive methods to detect food allergens. In this paper, an aptamer highly specific to egg white lysozyme was coupled to dendritic silver nanoparticles in order to perform surface enhanced Raman spectroscopy (SERS).

Highly sensitive and selective detection of nitrite ions using Fe3O4@SiO2/Au magnetic nanoparticles by surface-enhanced Raman spectroscopy.

A novel and pragmatic method was developed to detect the concentration of nitrite ions using Fe3O4@SiO2/Au magnetic nanoparticles (MNPs) by surface-enhanced Raman scattering (SERS). The as-prepared bifunctional nanocomposites can be used to simultaneously purify target molecules using external magnetic field and produce Raman fingerprint spectrum with trace level of target molecules. In acidic media, 4-aminothiophenol (4-ATP) molecules conjugated on Fe3O4@SiO2/Au MNPs were triggered by nitrite ions to form azo bonds, resulting in three new marker peaks on the SERS spectrum.

Alteration of the Nonsystemic Behavior of the Pesticide Ferbam on Tea Leaves by Engineered Gold Nanoparticles.

A model system consisting of a nonsystemic pesticide (ferbam), engineered gold nanoparticles (AuNPs) and a plant tissue (tea leaves) was investigated using surface enhanced Raman spectroscopy (SERS). Ferbam has no ability by itself to penetrate into tea leaves. When AuNPs were placed with ferbam onto the surface of tea leaves, however, the SERS signal of the ferbam-AuNPs complex was observed inside of the tea leaves.

Label-free mapping of single bacterial cells using surface-enhanced Raman spectroscopy.

Here we presented a simple, rapid and label-free surface-enhanced Raman spectroscopy (SERS) based mapping method for the detection and discrimination of Salmonella enterica and Escherichia coli on silver dendrites. The sample preparation was first optimized to maximize sensitivity. The mapping method was then used to scan through the bacterial cells adsorbed on the surface of silver dendrites.

Characterization of Lactococcus lactis response to ampicillin and ciprofloxacin using surface-enhanced Raman spectroscopy.

Decades of antibiotic use or misuse has resulted in antibiotic resistance in lactic acid bacteria, a group of common culture starters and probiotic microorganisms. This has urged researchers to study how lactic acid bacteria respond to antibiotics, so as to have a better strategy to identify and predict the antibiotic-resistant bacteria. This study aimed to characterize the biochemical profiles of Lactococcus lactis responding to antibiotics using surface-enhanced Raman spectroscopy (SERS).

Investigation of the solubility enhancement mechanism of rebaudioside D using a solid dispersion technique with potassium sorbate as a carrier.

Rebaudioside (Reb) D is a high intensity, natural sweetener that shows great potential for substituting sugar in sweetened beverages. However, Reb D is poorly water soluble, and thus, a solid dispersion technique was recently established to enhance its solubility. The purpose of this study was to elucidate the solubility enhancement mechanism of this solid dispersion material by employing Scanning Electron Microscopy (SEM), Raman spectroscopy, Fourier Transform Infrared spectroscopy (FT-IR) and X-ray Diffraction (XRD).

Evaluation of surface-enhanced Raman scattering detection using a handheld and a bench-top Raman spectrometer: a comparative study.

Surface enhanced Raman scattering (SERS) detection using a handheld Raman spectrometer and a bench-top Raman spectrometer was systemically evaluated and compared in this study. Silver dendrites were used as the SERS substrate, and two pesticides, maneb and pyrrolidine dithiocarbamate-ammonium salt (PDCA) were used as the analytes. Capacity and performance were evaluated based on spectral resolution, signal variation, quantitative capacity, sensitivity, flexibility and intelligence for SERS detection.

Rapid detection of acetamiprid in foods using surface-enhanced Raman spectroscopy (SERS).

Acetamiprid is a neonicotinoid pesticide that is commonly used in modern farming. Acetamiprid residue in food commodities can be a potential harm to human and has been implicated in the honey bee hive die off crisis. In this study, we developed rapid, simple, and sensitive methods to detect acetamiprid in apple juice and on apple surfaces using surface-enhanced Raman spectroscopy (SERS).

Development of a single aptamer-based surface enhanced Raman scattering method for rapid detection of multiple pesticides.

The objective of this study was to develop a simple and rapid method that could detect and discriminate four specific pesticides (isocarbophos, omethoate, phorate, and profenofos) using a single aptamer-based capture procedure followed by Surface Enhanced Raman Spectroscopy (SERS). The aptamer is a single stranded DNA sequence that is specific to capture these four pesticides. The thiolated aptamer was conjugated onto silver (Ag) dendrites, a nanostructure that can enhance the Raman fingerprint of pesticides, through Ag-thiol bonds.

Sensory and nutritional quality of white rice after residential storage for up to 30 years.

Rice is a staple food that may be packaged for long-term storage to ameliorate unpredictable circumstances such as crop failures and natural disasters. The sensory and nutritional quality of 18 samples of long grain white rice (11 regular, 7 parboiled) packaged in cans stored up to 30 years at ambient temperature in residential locations was evaluated. Hedonic scores for overall liking ranged from 5.

Semi-quantification of surface-enhanced Raman scattering using a handheld Raman spectrometer: a feasibility study.

The feasibility of utilizing a handheld Raman spectrometer for surface-enhanced Raman scattering detection was evaluated on the pesticide ferbam. A layman's "answer box" was established for semi-quantifying the risk level of ferbam. This study advanced the application of a handheld Raman spectrometer to on-site evaluation of trace amounts of analytes.