RESUMO
Plants have been used for the treatment of different diseases since 1100 BC. Catharanthus roseus is one of the medicinally important plants showing anti-tumor, anti-mutagenic and anti-microbial effects. L-asparaginase is extracted by C. roseus and is used for the development of biosensors. L-asparaginase breaks down asparagine into aspartic acid and ammonia, thus killing the tumor cells due to asparagine starvation. In the present study the L-asparaginase was extracted from C. roseus and immobilized in different matrixes such as agar, soil, clay and k-carrageenan. Out of the various immobilization techniques k-carrageenan gave the fastest response time, so it was choosen for the development of asparagine biosensor. In the leukemic blood samples the asparagine concentration was 10-2 to 10-3 M whereas in normal blood samples it was 10-5 to 10-6 M. The developed biosensor gave the fast response and were sensitive and reliable.