Modification of the Bio-Rad iQ-Check Listeria spp. Kit for the Detection of Listeria Species in Environmental Surfaces

2020 ◽  
Vol 103 (1) ◽  
pp. 216-222
Author(s):  
Nicole Klass ◽  
Benjamin Bastin ◽  
Erin Crowley ◽  
James Agin ◽  
Mike Clark ◽  
...  
Keyword(s):  
Method Comparison ◽  
Reference Method ◽  
Culture Method ◽  
Department Of Agriculture ◽  
Listeria Species ◽  
Modified Method ◽  
Environmental Surfaces ◽  
Pcr Technology ◽  
Inspection Service ◽  
Method Comparison Study

Abstract Background: The Bio-Rad iQ-Check Listeria spp. Kit uses real-time PCR technology for detection of Listeria species in select food matrixes and environmental surfaces. Objective: The iQ-Check Listeria spp. method was modified to reduce the enrichment medium volume for environmental sponges from 225 and 100 to 60 mL and to reduce the enrichment time for sponges and swabs from 25 ± 1 to as short as 18 h. The modified method was validated with stainless steel, polystyrene plastic, and sealed concrete using sponges or swabs with two different neutralizing buffers (Letheen Broth and HiCap™ Neutralizing Broth). In addition, the Bio-Rad Free DNA Removal Solution was used for all environmental samples. Methods: The iQ-Check Listeria spp. modified method was compared with the reference culture method in the U.S. Department of Agriculture Food Safety and Inspection Service Microbiology Laboratory Guidebook Chapter 8.10 using an unpaired study design. Results: In the method comparison study, the iQ-Check Listeria spp. modified method demonstrated no statistical difference in performance between candidate and reference method results or between presumptive and confirmed results for all environmental surfaces analyzed using HiCap Neutralizing Broth (World Bioproducts LLC) and Letheen broth. Conclusions: The modified iQ-Check Listeria spp. method is an effective method for the detection of Listeria species in environmental surfaces using both types of neutralizing buffer. Highlights: The method modification was granted based on the data collected.

scholarly journals Evaluation of the Solus One Listeria Method for the Detection of Listeria Species on Environmental Surfaces

2019 ◽  
Vol 102 (2) ◽  
pp. 570-579
Author(s):  
Elizabeth Tonner ◽  
Siobhan Kelly ◽  
Simon Illingworth ◽  
Nevin Perera ◽  
Benjamin Bastin ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Preparation Method ◽  
Method Comparison ◽  
Reference Method ◽  
Test System ◽  
Probability Of Detection ◽  
Comparison Study ◽  
Listeria Species ◽  
Environmental Surfaces ◽  
Method Comparison Study

Abstract Background: Solus One Listeria is designed to accurately detect Listeria species (Listeria grayi, L. innocua, L. ivanovii, L. marthii, L. monocytogenes, L. seeligeri, and L. welshimeri) from stainless steel and plastic environmental surface matrixes using an antibody-based technology test system paired with proprietary SOLO+ media and combined with manual or automated sample preparation method. Objective: Solus One Listeria was evaluated for inclusivity and exclusivity and a matrix comparison study fortwo environmental surfaces. Methods: Solus One Listeria was comparedwith the following reference method for the method comparison study: the U.S. Food and Drug Administration Bacteriological Analytical Manual Chapter 10 from stainless steel and plastic environmental surfaces. Both the manual and automatedpreparation methods were performed for stainless steel and plastic environmental surfaces. Results: For the inclusivity and exclusivityevaluation, Solus One Listeria correctly identified all 50 target organism isolates and correctly excluded all 30 nontarget strains that were analyzed. In the method comparison study, bothSolus One Listeria manual and automated preparation methods demonstrated no significant differences based on probability of detection statistical analysis between presumptive and confirmed results or between candidate and reference methodresults for two environmental surfaces after 22–30 h of enrichment time. Probability of detection analysis of Solus One Listeria method robustness, product consistency (lot-to-lot), and stability studies using the automated preparation method demonstrated no statistically significant differences. Conclusions: The data from the study support the product claims of Solus One Listeria for the accurate detection of Listeria species, using both the manual and automated methods (using theDynex DS2 instrument), on both environmental surfaces analyzed.

Romer Labs RapidChek®Listeria monocytogenes Test System for the Detection of L. monocytogenes on Selected Foods and Environmental Surfaces

2018 ◽  
Vol 101 (5) ◽  
pp. 1490-1507
Author(s):  
Gregory Juck ◽  
Verapaz Gonzalez ◽  
Ann-Christine Olsson Allen ◽  
Meredith Sutzko ◽  
Kody Seward ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Reference Method ◽  
Test System ◽  
Probability Of Detection ◽  
Department Of Agriculture ◽  
Detection Analysis ◽  
Media System ◽  
Reference Methods ◽  
Environmental Surfaces ◽  
Inspection Service

Abstract The Romer Labs RapidChek®Listeria monocytogenes test system (Performance Tested Method 011805) was validated against the U.S. Department of Agriculture-Food Safety and Inspection Service Microbiology Laboratory Guidebook (USDA-FSIS/MLG), U.S. Food and Drug Association Bacteriological Analytical Manual (FDA/BAM), and AOAC Official Methods of Analysis (AOAC/OMA) cultural reference methods for the detection of L. monocytogenes on selected foods including hot dogs, frozen cooked breaded chicken, frozen cooked shrimp, cured ham, and ice cream, and environmental surfaces including stainless steel and plastic in an unpaired study design. The RapidChek method uses a proprietary enrichment media system, a 44–48 h enrichment at 30 ± 1°C, and detects L. monocytogenes on an immunochromatographic lateral flow device within 10 min. Different L. monocytogenes strains were used to spike each of the matrixes. Samples were confirmed based on the reference method confirmations and an alternate confirmation method. A total of 140 low-level spiked samples were tested by the RapidChek method after enrichment for 44–48 h in parallel with the cultural reference method. There were 88 RapidChek presumptive positives. One of the presumptive positives was not confirmed culturally. Additionally, one of the culturally confirmed samples did not exhibit a presumptive positive. No difference between the alternate confirmation method and reference confirmation method was observed. The respective cultural reference methods (USDA-FSIS/MLG, FDA/BAM, and AOAC/OMA) produced a total of 63 confirmed positive results. Nonspiked samples from all foods were reported as negative for L. monocytogenes by all methods. Probability of detection analysis demonstrated no significant differences in the number of positive samples detected by the RapidChek method and the respective cultural reference method.

SDIX RapidChek™ Listeria F.A.S.T.™ Environmental Test System for the Detection of Listeria species on Environmental Surfaces

2012 ◽  
Vol 95 (3) ◽  
pp. 850-859 ◽  
Author(s):  
Mark T Muldoon ◽  
Anne-Christine Olsson Allen ◽  
Vera Gonzales ◽  
Meredith Sutzko ◽  
Klaus Lindpaintner
Keyword(s):  
Reference Method ◽  
Storage Conditions ◽  
Test System ◽  
Test Method ◽  
Broth Culture ◽  
Bacterial Strains ◽  
Chi Square ◽  
Listeria Species ◽  
Environmental Surfaces ◽  
Inspection Service

Abstract The SDIX RapidChekTMListeria F.A.S.T. test system was validated against the U. S. Department of Agriculture-Food Safety and Inspection Service (USDA-FSIS) cultural reference method for the detection of Listeria species on stainless steel, plastic, rubber, and painted concrete. The SDIX method uses a proprietary RapidChek Listeria enrichment media for a one-step, 24–40 h enrichment at 30°C, and detects Listeria on an immunochromatographic lateral flow device in 10 min. Different Listeria species were used to spike each of the environmental surfaces. Environmental surfaces were spiked at levels ranging from 50 to 400 CFU/surface (1 in.2 swabs for painted concrete, 4 in.2 for sponge). A total of 120 spiked samples were tested by the SDIX method at 24 and 40 h and the cultural reference method. Total confirmed positives were 49, 54, and 48 for the SDIX 24 h method, the SDIX 40 h method, and the USDA-FSIS cultural reference method, respectively. Nonspiked samples from all environmental surfaces were reported as negative for Listeria spp. by all methods. The overall Chi square was 0.017 (P = 0.104) and 0.611 (P = 0.566) after a 24 and 40 h enrichment, respectively, indicating that the test method was equivalent in performance to the reference method at both enrichment times. The SDIX method was evaluated for the detection of 50 Listeria and 35 non-Listeria bacterial strains. All 50 Listeria strains were detected by the method (100% sensitivity). Five out of 35 non-Listeria species gave light test signals when grown in nonselective broth culture and tested undiluted. However, when grown in the RapidChek Listeria F.A.S.T. proprietary media, only one bacterial strain (Staphylococcus aureus) was detected, giving a very low test signal (97% specificity). The method was shown to be robust toward several alterations in testing and storage conditions.

Method Modification for the Atlas Listeria Environmental LE Detection Assay Using FoodChek Actero Listeria Enrichment Media and Half-Fraser Media for the Detection of Listeria spp. from Environmental Surfaces

2018 ◽  
Vol 101 (2) ◽  
pp. 562-576
Author(s):  
Brett Maroni ◽  
Tucker Lopez ◽  
Cambria Neal ◽  
Sarah Verver ◽  
Celina Puente ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Reference Method ◽  
Common Species ◽  
Sample Volume ◽  
Probability Of Detection ◽  
Department Of Agriculture ◽  
Environmental Surfaces ◽  
Detection Assay ◽  
Inspection Service ◽  
High Level

Abstract Two candidate method modifications for the Atlas Listeria Environmental LE Detection Assay were compared with the U.S. Department of Agriculture (USDA)-Food Safety and Inspection Service Microbiology Laboratory Guidebook 8.09 (MLG 8.09) method for detection of Listeria spp. on stainless steel, polyvinyl chloride (PVC), and sealed concrete surfaces. For LE candidate method 1, samples were enriched in FoodChek Actero Listeria Enrichment Media [ALEM; Performance Tested MethodSM (PTM) 111201] at 35 ± 2°C for 18 to 24 h and evaluated for a range of analytical sample volumes. For LE candidate method 2, the current Roka PTM using 90 mL of Half-Fraser broth for enrichment at 35 ± 2°C was evaluated at 24 h with a reduced sample volume. These comparisons were made in multiple studies across the three environmental surfaces. Within each method and study, a total of 5 samples were uninoculated, 20 samples were inoculated with Listeria spp. at a low level to target fractional positivity, and 5 samples were inoculated with Listeria spp. at a high level to approach a probability of detection of 1. Inclusivity and exclusivity studies were also conducted for the LE method in combination with Half-Fraser and ALEM. The Atlas Listeria Environmental LE Detection Assay detected all 50 inclusive organisms, including 25 strains of L. monocytogenes and 5 strains of each of the other five common species of Listeria (L. innocua, L. welshimeri, L. ivanovii, L. seeligeri, and L. grayi) and none of the 30 exclusive organisms across all media and with both 200 and 2000 µL sample volumes. For the LE candidate method 1 studies, no significant differences were observed within the Roka ALEM method at 18, 20, or 24 h and for both the 200 and 2000 µL sample volumes as compared with the paired culture outcome. However, the ALEM method performed significantly better as compared with the unpaired reference method for sealed concrete and stainless steel. For the LE candidate method 2 studies, no significant differences were observed within the Roka HF method at 24 h for the 200 and 2000 µL samples as compared with the paired culture outcomes and unpaired reference method outcomes across the surfaces. The independent laboratory studies observed no significant differences in performance between the USDA/MLG 8.09 reference method and candidate methods 1 or 2, respectively, across the evaluated parameters. Overall, the candidate method 1 modification parameters and candidate method 2 sample parameters for the Atlas Listeria Environmental LE Detection Assay were statistically equivalent to or better than the reference method for detection of Listeria spp. on stainless steel, PVC, and sealed concrete surfaces, providing greater flexibility in method application for end users.

VIDAS® Listeria species Xpress (LSX)

2013 ◽  
Vol 96 (2) ◽  
pp. 242-245 ◽  
Author(s):  
Ronald Johnson ◽  
John Mills
Keyword(s):  
Stainless Steel ◽  
Reference Method ◽  
Culture Method ◽  
Culture Methods ◽  
Chi Square ◽  
Listeria Species ◽  
Standard Culture ◽  
Inspection Service ◽  
Chi Square Analysis ◽  
Positive Results

Abstract The AOAC GovVal study compared the VIDAS®Listeria species Xpress (LSX) to the Health Products and Food Branch MFHPB-30 reference method for detection of Listeria on stainless steel. The LSX method utilizes a novel and proprietary enrichment media, Listeria Xpress broth, enabling detection of Listeria species in environmental samples with the automated VIDAS in a minimum of 26 h. The LSX method also includes the use of the chromogenic media, chromID™ Ottaviani Agosti Agar (OAA) and chromID™ Lmono for confirmation of LSX presumptive results. In previous AOAC validation studies comparing VIDAS LSX to the U. S. Food and Drug Administration's Bacteriological Analytical Manual (FDA-BAM) and the U. S. Department of Agriculture-Food Safety and Inspection Service (USDA-FSIS) reference methods, the LSX method was approved as AOAC Official Method2010.02 for the detection of Listeria species in dairy products, vegetables, seafood, raw meats and poultry, and processed meats and poultry, and as AOAC Performance Tested Method 100501 in a variety of foods and on environmental surfaces. The GovVal comparative study included 20 replicate test portions each at two contamination levels for stainless steel where fractionally positive results (5–15 positive results/20 replicate portions tested) were obtained by at least one method at one level. Five uncontaminated controls were included. In the stainless steel artificially contaminated surface study, there were 25 confirmed positives by the VIDAS LSX assay and 22 confirmed positives by the standard culture methods. Chi-square analysis indicated no statistical differences between the VIDAS LSX method and the MFHPB-30 standard methods at the 5% level of significance. Confirmation of presumptive LSX results with the chromogenic OAA and Lmono media was shown to be equivalent to the appropriate reference method agars. The data in this study demonstrate that the VIDAS LSX method is an acceptable alternative method to the MFHPB-30 standard culture method for the detection of Listeria species on stainless steel.

scholarly journals The Validation of the VereBeef™ Detection Kit

2019 ◽  
Vol 102 (2) ◽  
pp. 508-524
Author(s):  
Dawn Qian Liu ◽  
Mitsuharu Sato ◽  
Wei Ling Tan ◽  
Grace Pei Wen Khoo ◽  
Kiel Fisher ◽  
...  
Keyword(s):  
False Negative ◽  
Method Comparison ◽  
Department Of Agriculture ◽  
Lab On Chip ◽  
E Coli ◽  
Qualitative Detection ◽  
Assay Performance ◽  
On Chip ◽  
Inspection Service ◽  
Method Comparison Study

Abstract VereBeef™ Detection Kit, incorporating both multiplex PCR and microarray technologies on a lab-on-chip platform, is intended for qualitative detection and differentiation of Escherichia coli O157:H7, E. coli O26, E. coli O45, E. coli O103, E. coli O111, E. coli O121, E. coli O145, Shiga toxin-producing E. coli (STEC) virulence factors (stx1A, stx2A, eae), and Salmonella species in one test using raw beef trim samples. This product underwent extensive evaluations, including inclusivity-exclusivity, method comparison, robustness, lot-to-lot variability, and stability studies. The inclusivity/exclusivity study demonstrated that VereBeef Detection Kit specifically detects and identifies target analytes without occurrence of false-positive and false-negative detection. In the method comparison study, the performance of the VereBeef Detection Kit was compared with U.S. Department of Agriculture Food Safety and Inspection Service Microbiology Laboratory Guidebook’s methods for target organism detection in raw beef trim using E. coli O157:H7 single inoculation and Salmonella and non-O157 STEC dual inoculation. Data demonstrated equivalence in both methods. The robustness study showed that changesin the test parameters do not impact assay performance. Collectively, VereBeef Detection Kit is able to detect target pathogens in raw beef trim with a minimum enrichment time of 8 h for E. coli O157:H7 detection and 10 h for Salmonella and non-O157 STEC detection.

scholarly journals The Validation of the Sample6 DETECTTM HT/L for AOAC Research Institute

2018 ◽  
Vol 101 (5) ◽  
pp. 1584-1592
Author(s):  
Kakolie Banerjee ◽  
Brittney Pierson ◽  
Chuxuan Hu ◽  
Elijah Carrier ◽  
Lauren Malsick ◽  
...  
Keyword(s):  
Pathogen Detection ◽  
Incubation Temperature ◽  
Detection System ◽  
Reference Method ◽  
Culture Method ◽  
The Elderly ◽  
Sample Volume ◽  
Test Portion ◽  
Environmental Surfaces ◽  
The Matrix

Abstract Background: Listeria spp. are an important foodborne human pathogen because of their ability to cause disease and high mortality in individuals, particularly pregnant women, neonates, the elderly, immunocompromised individuals, and children. The Sample6 DETECTTM HT/L Kit is a semi-automated qualitative pathogen detection system designed to detect Listeria spp. (L. monocytogenes, L. innocua, L. ivanovii, L. seeligeri, L. welshimeri, and L. marthii) in environmental samples using the Sample6 BioIlluminationTM technology. Objective: The study was done to evaluate the Sample6 DETECT HT/L Kit. The assay was evaluated for inclusivity, exclusivity, robustness, product consistency, and stability, and a matrix study of one environmental surface. Methods: The performance of the Sample6 DETECT HT/L was compared with U.S. Food and Drug Administration reference culture method for Listeria using an unpaired study design. Results: The Sample6 DETECT HT/L assay correctly identified all 50 inclusivity isolates and correctly excluded all 30 nontarget strains evaluated. The assay was not affected by minor variations in incubation temperature and time, or sample volume. Results across three production lots spanning the shelf life of the assay were consistent. In the matrix study, the Sample6 DETECT HT/L for Listeria correctly identified each test portion for the presence or absence of Listeria, and there were no statistically significant differences between candidate and reference method results. Conclusions: The data collected in this study demonstrate that the Sample6 DETECT HT/L assay is a reliable method for the detection of Listeria spp. on stainless-steel environmental surfaces after 22 h of enrichment.

Comparative Evaluation of Veriflow®Listeria Species to USDA Culture-Based Method for the Detection of Listeria spp. in Food and Environmental Samples

2017 ◽  
Vol 100 (5) ◽  
pp. 1434-1444 ◽  
Author(s):  
Adam C Joelsson ◽  
Shawn P Terkhorn ◽  
Ashley S Brown ◽  
Amrita Puri ◽  
Benjamin J Pascal ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Ceramic Tile ◽  
Pcr Amplification ◽  
Reference Method ◽  
Probability Of Detection ◽  
Complex Data ◽  
Listeria Species ◽  
Environmental Surfaces ◽  
Study Results ◽  
Significant Difference

Abstract Veriflow®Listeria species (Veriflow LS) is a molecular-based assay for the presumptive detection of Listeria spp. from environmental surfaces (stainless steel, sealed concrete, plastic, and ceramic tile) and ready-to-eat (RTE) food matrixes (hot dogs and deli meat). The assay utilizes a PCRdetection method coupled with a rapid, visual, flow-based assay that develops in 3 min post-PCR amplification and requires only a 24 h enrichment for maximum sensitivity. The Veriflow LS system eliminates the need for sample purification, gel electrophoresis, or fluorophore-based detection of target amplification and does not require complex data analysis. This Performance Tested MethodSM validation study demonstrated the ability of the Veriflow LS assayto detect low levels of artificially inoculated Listeria spp. in six distinct environmental and food matrixes. In each unpaired reference comparison study, probability of detection analysis indicated that there was no significant difference between the Veriflow LS method and the U.S. Department of Agriculture Food Safety and Inspection Service Microbiology Laboratory Guide Chapter 8.08 reference method. Fifty-one strains of various Listeria spp. were detected in the inclusivity study, and 35 nonspecific organisms went undetected in the exclusivity study. The study results show that the Veriflow LS is a sensitive, selective, and robust assay for the presumptive detection of Listeria spp. sampled from environmental surfaces (stainless steel, sealed concrete, plastic, and ceramic tile) and RTE food matrixes (hot dogs and delimeat).

scholarly journals IFCC Reference System for Measurement of Hemoglobin A1c in Human Blood and the National Standardization Schemes in the United States, Japan, and Sweden: A Method-Comparison Study

2004 ◽  
Vol 50 (1) ◽  
pp. 166-174 ◽  
Author(s):  
Wieland Hoelzel ◽  
Cas Weykamp ◽  
Jan-Olof Jeppsson ◽  
Kor Miedema ◽  
John R Barr ◽  
...  
Keyword(s):  
Reference System ◽  
Clinical Chemistry ◽  
Method Comparison ◽  
Reference Method ◽  
The United States ◽  
Reference Laboratory ◽  
Regression Equations ◽  
National Programs ◽  
Method Comparison Study ◽  
The Relationship

Abstract Background: The national programs for the harmonization of hemoglobin (Hb)A1c measurements in the US [National Glycohemoglobin Standardization Program (NGSP)], Japan [Japanese Diabetes Society (JDS)/Japanese Society of Clinical Chemistry (JSCC)], and Sweden are based on different designated comparison methods (DCMs). The future basis for international standardization will be the reference system developed by the IFCC Working Group on HbA1c Standardization. The aim of the present study was to determine the relationships between the IFCC Reference Method (RM) and the DCMs. Methods: Four method-comparison studies were performed in 2001–2003. In each study five to eight pooled blood samples were measured by 11 reference laboratories of the IFCC Network of Reference Laboratories, 9 Secondary Reference Laboratories of the NGSP, 3 reference laboratories of the JDS/JSCC program, and a Swedish reference laboratory. Regression equations were determined for the relationship between the IFCC RM and each of the DCMs. Results: Significant differences were observed between the HbA1c results of the IFCC RM and those of the DCMs. Significant differences were also demonstrated between the three DCMs. However, in all cases the relationship of the DCMs with the RM were linear. There were no statistically significant differences between the regression equations calculated for each of the four studies; therefore, the results could be combined. The relationship is described by the following regression equations: NGSP-HbA1c = 0.915(IFCC-HbA1c) + 2.15% (r2 = 0.998); JDS/JSCC-HbA1c = 0.927(IFCC-HbA1c) + 1.73% (r2 = 0.997); Swedish-HbA1c = 0.989(IFCC-HbA1c) + 0.88% (r2 = 0.996). Conclusion: There is a firm and reproducible link between the IFCC RM and DCM HbA1c values.

AES Chemunex ADIAFOOD Detection System for Listeria spp. Environmental Sample Testing

2012 ◽  
Vol 95 (2) ◽  
pp. 435-445
Author(s):  
Daniel Plante ◽  
Yvan P Côté ◽  
louisiane Giovannetti1
Keyword(s):  
Stainless Steel ◽  
Environmental Sample ◽  
Pathogen Detection ◽  
Detection System ◽  
Realtime Pcr ◽  
Listeria Species ◽  
Environmental Surfaces ◽  
Sample Testing ◽  
Pcr Technology

Abstract The ADIAFOOD Detection System for the detection of Listeria species from environmental surfaces is based on realtime PCR technology and allows rapid pathogen detection within 21 h. The strength of the ADIAFOOD technology resides in its ability to rapidly and accurately detect Listeria species present on surfaces, such as stainless steel, plastic, ceramic, and sealed concrete. The technology is easy to use and versatile.

Sign in / Sign up

Export Citation Format

Share Document