This technology includes human F(ab’)2 fragments specific for anthrax lethal factor for the development of a lateral flow immunoassay for Bacillus anthracis Lethal Factor. The F(ab’)2 fragments are generated from a Human Combinatorial Antibody Library (HuCAL) and are highly specific with high affinity. A multi-step process was utilized beginning by screening a phage display library with over 45 billion functional human antibody specificities. The primary screen against Bacillus anthracis Lethal Factor (LF) generated 360 positive clones. This was followed up by a step to reduce non-specific interactions to normal human serum resulting in more specific F(ab’)2. -Bio- Layer Interferometry identified 95 high affinity clones. Sequencing of the 20 highest affinity clones revealed 12 unique F(ab’)2 antibodies. These 12 antibodies were evaluated for LF detection using sandwich ELISAs. The F(ab’)2 were screened as both capture and detection antibodies to identify possible LF detection pairs.