Countercurrent chromatography: liquid-liquid partition chromatography without solid support

The liquid-liquid partition chromatographic system reported here involves a long helix of narrow-bore tubing. When the coiled tube is filled with one phase of a two-phase system and fed with the other phase, phase-interchange takes place in each turn of the coil, leaving a segment of the former phase as the stationary phase. Consequently, solutes present in either phase are subjected to a multistep partition process. The column efficiency, estimated on a separation of dinitrophenyl amino acids, is comparable to that of gas chromatography.     

Device Applications of Side-Chain Ferroelectric Liquid Crystalline Polymer Films

Side-chain ferroelectric liquid crystalline polymers are currently used in a number of applications, including displays and electrical sensors. Comparisons with existing technologies and materials indicate that relative to ceramics, such polymers have lower figures of merit but offer greater durability in sensor applications.     

Artificial placenta: two days of total extrauterine support of the isolated premature lamb fetus

A premature lamb fetus was totally sustained by extracorporeal perfusion with the use of a silicone-membrane blood oxygenator and parenteral nutritional support. The fetus remained in a metabolically stable state lasting several days.     

Countercurrent chromatography with flow-through coil planet centrifuge

We have developed a new method of countercurrent chromatography which employs a vertical helical tube in the centrifugal field. The helical tube is arranged so that it does not rotate as it revolves, thus eliminating the need for rotating seals. When the gyrating tube is filled with either phase and the other phase is introduced into the tube in the proper direction, an equilibrium state results in which the two phases are split into multiple alternating segments within the coil. Each phase oscillates to and fro with the rotation as the moving phase is steadily eluted out through the other end of the tube. Consequently, solutes introduced into the tube are subjected to a rapid partition process, resulting in an efficient chromatographic separation without the complications arising from solid supports. The method is illustrated by the microanalytical separation of dinitrophenyl amino acids and can be used on a preparative scale.