|
| US4042350 | 20 Jun 1975 | 16 Ago 1977 | National Research Development Corporation | Methods and applications of preparative scale chromatography |
| US4180389 | 13 Nov 1978 | 25 Dic 1979 | Envirochem Inc. | Isolation and concentration of sample prior to analysis thereof |
| US5135549 | 30 Ene 1991 | 4 Ago 1992 | The Board of Trustees of Southern Illinois University | Chromatographic technique and apparatus |
| US5196039 | 6 Mar 1992 | 23 Mar 1993 | Southern Illinois University at Carbondale | Apparatus and method of multi-dimensional chemical separation |