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Leonardo Canaán-Haden

Publications and source records attributed to Leonardo Canaán-Haden.

2 recordsLinked to original sources

High-performance reverse phase chromatography with fluorescence detection assay for characterization and quantification of pneumococcal polysaccharides.

A methods using high-performance reverse phase (RP) chromatography with fluorescence detection, has been developed to determine the composition and identity of Streptococcus pneumoniae capsular polysaccharide used in formulating conjugate vaccine for prevention of pneumococcal infection. For the monosaccharide composition, the polysaccharides were subjected to hydrofluoric acid (HF) hydrolysis followed by trifluoroacetic acid (TFA). After acid hydrolysis, the released monosaccharides were re-N-acetylated and labeled with 2-aminobenzamide (2AB) by reductive amination reaction. High-performance RP chromatography was performed on C18 TSKODS 120T column. Nuclear magnetic resonance was used to confirm chemical structure and purity of pneumococcal capsular polysaccharides.

Chromatography↗

A multivalent recombinant antibody fragment specific for carcinoembryonic antigen.

In the present paper we report the development of a bivalent scFv (single-chain Fv) antibody fragment, starting from a mouse mAb (monoclonal antibody) specific for CEA (carcinoembryonic antigen) that has received approval for in vivo radioimmunodiagnosis in humans. The diabody is well expressed in Escherichia coli, is easily purified by a combination of immobilized metal ion affinity chromatography and gel filtration and exhibits high affinity and specificity for CEA, comparable with those of the original mAb. Biodistribution experiments in athymic nude mice transplanted with human CEA+ cancer cells showed that the 125I-labelled diabody preferentially localizes in the tumour tissue and that retention is still high 48 h after injection. The diabody can be advantageous for some in vivo tumour targeting applications, due to the faster clearance derived from its smaller molecular mass.

Amino Acid Sequence↗