Evaluation of Lateral-Flow Clostridium botulinum Neurotoxin Detection Kits for Food Analysis

Abstract

The suitability and sensitivity of two in vitro lateral-flow assays for detecting Clostridium botulinum neurotoxins (BoNTs) in an assortment of foods were evaluated. Toxin extraction and preparation methods for various liquid, solid, and high-fat-content foods were developed. The lateral-flow assays, one developed by the Naval Medical Research Center (Silver Spring, MD) and the other by Alexeter Technologies (Gaithersburg, MD), are based on the immunodetection of BoNT types A, B, and E. The assays were found to be rapid and easy to perform with minimum requirements for laboratory equipment or skills. They can readily detect 10 ng/ml of BoNT types A and B and 20 ng/ml of BoNT type E. Compared to other in vitro detection methods, these assays are less sensitive, and the assessment of a result is strictly qualitative. However, the assay was found to be simple to use and to require minimal training. The assays successfully detected BoNT types A, B, and E in a wide variety of foods, suggesting their potential usefulness as a preliminary screening system for triaging food samples with elevated BoNT levels in the event of a C. botulinum contamination event.

Interlaboratory and Interstudy Reproducibility of a Novel Lateral-Flow Device and Influence of Antifungal Therapy on Detection of Invasive Pulmonary Aspergillosis

“…These lateral-flow devices (LFDs) have been used in the diagnosis of diseases caused by bacteria, fungi, toxins, and viruses, including HIV (9)(10)(11)(12)(13). We have previously reported on the successful incorporation of an Aspergillus-specific murine monoclonal antibody (MAb) into an LFD.…”

Development of Enzyme-Linkage Immunosorbent Assay Against Type B of Clostridium Botulinum: A Preliminary Study

“…The assay is able to detect up to one unit dose of one mouse lethal dose (1 MLD), which is equivalent to approximately 10 pg/ml of neurotoxins (Sharma et al, 2005). Hence, this method is categorized quite sensitive.…”

“…Furthermore it takes special skills, animal ethics concerns, as well as the specificity of neurotoxins detected is still very limited. It also needs quite long time to get results, which is about 4 days or more (Sharma et al, 2005). Consequently several methods have been developed ranging from ELISA (Dezfulian et al, 1984;Witcome et al, 1999), immunoaffinity chromatographic column test (Gessler et al, 2005), fluorogenic assay (Anne et al, 2001), up to the bio-molecular test such as PCR (Fach et al, 1995;Braconnier et al, 2001;Kimura et al, 2001;Lindstrom et al, 2001;Fach et al, 2002).…”

Complexity of Botulinum Neurotoxins: Challenges for Detection Technology

“…Several LFAs for the detection of different BoNT serotypes have been developed with detection limits usually between 0.3 and 250 ng/mL (Chiao et al 2004(Chiao et al , 2008aKlewitz et al 2006;Attrée et al 2007;Han et al 2007). Sharma and co-workers evaluated two commercial products on spiked food samples and found detection limits of above 20 ng/mL for BoNT complexes of serotypes A, B, and E (Sharma et al 2005). Others reported that some commercial tests were unable to recognize the purified holotoxin but detected the toxin complexes only (Gessler et al 2007).…”