The Center for Alternatives to Animal Testing is an academic center affiliated with the Division of Toxicological Sciences in the Department of Environmental Health Sciences of the Johns Hopkins University Bloomberg School of Public Health.

 

Johns Hopkins School of Public Health

Research Grants 1999-2000

Development of Enzymatic Inhibition Bioelectrodes for the Direct Determination of Phycotoxins

Francesco Botré, PhD
La Sapienza, Rome, Italy

The goal of this research program is to develop biosensor-based analytical methods for the analysis of phycotoxins (toxins produced by algae which are responsible, when ingested, of various diseases in man) in mussels. These new methods should at least integrate, but hopefully substitute, the commonly applied "global toxicity tests", i.e. highly invasive bioassays on mammalians (in which the mussel extract is either injected or mixed with the food), which are, at present, the only internationally recognized methods for the screening of these toxins in seafood.

Enzymatic inhibition biosensors (EIBs), being a particular form of response-based analytical devices, would reveal a good compromise between purely "biological" and "physico-chemical" techniques. An EIB represents in fact a sort of "artificial bioindicator", partially combining the flexibility of a biological effect-based test and the selectivity of a physico-chemical assay. In other words, the screening analysis to detect the possible contamination of seafood by phycotoxins would be carried out by "feeding the biosensor" and monitoring the alteration of a specific biochemical parameter, rather than "feeding the mouse" and following the development of generic toxic effects.

The first part of the project is aimed to develop a lab-scale prototype for the direct determination of algal toxins belonging to the DSP ("diarrhetic shellfish poisoning") group; the same analytical approach will then be extended to the assay of other phycotoxins. A further development would be the realization of disposable biosensors, produced by the technique of screen printing, to be used for timely planned monitoring of risky areas and possibly also for shipboard operations.