Abstract: A method for determining a molecule A comprising a sample of molecules capable of participating in formation of triplex structures is useful for sensitive determination. The principle can be used to determine any kind of analytes.

Abstract: The present invention relates to a polypeptide comprising a characteristic amino acid sequence derived from the Plasmodium falciparum antigen GLURP, a polypeptide which is recognized by an antibody raised against or reactive with a polypeptide comprising said characteristic amino acid sequence and/or an antibody reactive with native GLURP, a nucleic acid molecule (DNA-fragment) encoding said polypeptide, an expression vector carrying the nucleic acid molecule, an organism expressing said nucleic acid molecule so as to produce said polypeptide, a monoclonal antibody directed against said polypeptide, a diagnostic agent comprising said antibody or said polypeptide for use in assaying Plasmodium falciparum infection and thus diagnosing malaria, and the use of said antibody or said polypeptide for therapeutic purposes, e.g. as a component in a vaccine.