CCD Based Detector for Detection of Abrin Toxin Activity.

Area of Science:

• Biochemistry
• Toxicology
• Biotechnology

Background:

• Abrin, a potent toxin from Rosary Pea seeds, poses a bioterrorism risk.
• Existing detection methods often lack specificity for active toxin, failing to distinguish threats from inactivated forms.
• Assessing toxin activity is crucial for accurate risk evaluation.

Purpose of the Study:

• To develop and evaluate a simple, low-cost CCD detector system for measuring abrin activity.
• To compare colorimetric and fluorometric cell-based assays for abrin detection sensitivity.
• To investigate the thermal inactivation of abrin in different media.

Main Methods:

• Utilized a CCD detector with MTT-formazan colorimetric assay measuring mitochondrial dehydrogenase suppression in Vero cells.
• Employed a fluorometric assay measuring abrin suppression of green fluorescent protein (GFP) expression in transduced Vero and HeLa cells.
• Studied abrin thermal inactivation in PBS and milk using the GFP-Vero cell assay.

Main Results:

• The colorimetric assay achieved a detection limit of 10 pg/mL, comparable to fluorometric assays in HeLa cells.
• A 100-fold increase in sensitivity was observed using GFP-transduced Vero cells.
• Thermal inactivation studies showed complete inactivation at 100°C for 5 min in PBS and milk, but 63°C for 30 min was effective only in PBS.

Conclusions:

• A low-cost CCD detector system coupled with cell-based assays provides a sensitive method for detecting active abrin.
• GFP-transduced Vero cells offer enhanced sensitivity for abrin activity detection.
• Understanding abrin thermal stability in various media is vital for decontamination and safety protocols.