Development and validation of an ELISA kit for the detection of ricin toxins from biological specimens and environmental samples

Abstract

Ricin is a toxin that can be easily extracted from seeds of Ricinus communis plants. Ricin is considered to be a major bio-threat as it can be freely and easily acquired in large quantities. A deliberate release of such toxin in civilian populations would very likely overwhelm existing public health systems, resulting in public fear and social unrest. There is currently no commercially available or FDA-approved prophylaxis such as vaccines, or therapeutic antitoxins or antidotes, available for ricin intoxication. Patient treatment is typically supportive care based on symptoms, often designed to reinforce the body's natural response. This paper describes the development and validation of a robust ELISA test kit, which can be used to screen for ricin in biological specimens such as whole blood and faeces. Faecal specimens are shown in this study to have better diagnostic sensitivity and a wider diagnostic window compared to whole blood. From these results, it is concluded that faeces is the most suitable clinical specimen for diagnosis of ricin poisoning via the oral route. The ELISA test kit can also detect ricin in environmental samples. An advantage of this ELISA kit over other commercial off-the-shelf (COTS) detection kits currently on the market that are developed to screen environmental samples only is its ability to diagnose ricin poisoning from clinical specimens as well as detect ricin from environmental samples.

Detecting Biothreat Agents: From Current Diagnostics to Developing Sensor Technologies

“…This is especially true in the case of ricin, where most of the sensing methods are focused on environmental samples. Chen et al proposed a diagnostic test based on an ELISA kit valid for both scenarios . In this assay, a biotinylated polyclonal antibody is used to first coat the ELISA plate, and following sample exposure, HRP-conjugated streptavidin was used to reveal the positive samples indirectly by loss of signal.…”

“…Chen et al proposed a diagnostic test based on an ELISA kit valid for both scenarios. 1026 In this assay, a biotinylated polyclonal antibody is used to first coat the ELISA plate, and following sample exposure, HRP-conjugated streptavidin was used to reveal the positive samples indirectly by loss of signal. This method was used as a diagnostic tool in environmental (aerosol), human (feces and blood), and infected animal samples (feces, blood, and urine).…”

Multiple metabolic pathways are predictive of ricin intoxication in a rat model

“…Ricin ELISA kits (MP Biomedical) were kindly supplied by DST-G (Australia) and DSO National Laboratories (Singapore) for use in this work. The development of this assay is described in (Chen et al 2014) and consists of a 32-well ELISA plate pre-coated with ricin-A chain specific monoclonal antibodies RA999 (Meridian Life Science, USA) and 7G12, (US Army Medical Research Institute of Infectious Diseases (Dertzbaugh et al 2005). Blood samples from each exposed animal (30 μl) were added to 60 μl of Sample treatment buffer (STB) pre-aliquoted into the wells of a non-binding microwell plate.…”

“…ELISAs can be very sensitive being able to detect ricin at levels as low as 20 pg per 100 μl of tissue extract (Leith et al 1988). They can also be highly adaptable showing efficacy in multiple clinical specimens and environmental samples including blood, urine and stool (Chen et al 2014). The uptake of ricin into tissues is rapid (Moshiri et al 2016).…”

Combination of inverted pyramidal nanovoid with silver nanoparticles to obtain further enhancement and its detection for ricin

“…We have detected and distinguished a kind of phytotoxin, ricin, using our combined SERS substrate. Compared with other detection method, such as enzyme-linked immunosorbent assay (ELISA) [ 25 ], SERS can identify the toxin rapidly with only a small amount of sample.…”