['It is known that total PSA values are often greater than the sum total of free-PSA (f-PSA) and PSA-ACT complex. It is primarily because other PSA complexes are present in the patient serum and currently cannot be quantified. Our studies were aimed in developing methodology that will permit recovery of all molecular forms of PSA from various biological fluids.', 'Thiophilic interaction (3S,T-gel) chromatography procedure was used to isolate various PSA molecular forms present in biological fluids. f-PSA and PSA complexes were shown to have strong affinity for T-gel. PSA forms eluted from the column were analyzed by SDS-PAGE/Western blot and were identified by immunostaining with antibody-specific to PSA and to various protease inhibitors. The identity of PSA complexes was also confirmed by Enzyme-linked Immunosorbent-assay (ELISA).', 'One step affinity chromatography procedure (3S,T-gel) was used to isolate different molecular forms of PSA in seminal plasma, patient sera, and in prostate cancer cell culture medium. Seminal plasma was shown to contain f-PSA, PSA-ACT, PSA-A2M, and PSA-PCI. Sera from prostate cancer patients at different stages of the disease contained f-PSA, PSA-ACT, and PSA-A2M. Besides these PSA forms, some patients at late stage of the disease (T3 and T4) also contained two additional PSA-complexes that have not been identified as of yet. Conditioned medium from LNCaP cells was shown to contain f-PSA, PSA-ACT, and PSA-A2M complexes.'] Does thiophilic interaction chromatography facilitate detection of various molecular complexes of prostate-specific antigen in biological fluids?