Action potentials are propagated down the motoneuron, depolarize each adjacent region to threshold. Finally, the presynaptic terminal is depolarized, and this depolarization causes voltage-gated Ca2+ channels in the presynaptic membrane to open.

TLS Online TPP Program

#Id: 2801

#Unit 13. Methods in Biology

Normal-phase liquid chromatography form of partition chromatography

TLS Online TPP Program

#Id: 2802

#Unit 13. Methods in Biology

In Normal-phase liquid chromatography the stationary phase is polar and the mobile phase relatively non-polar.

TLS Online TPP Program

#Id: 2803

#Unit 13. Methods in Biology

In NPLC the most popular stationary phase is an alkylamine bonded to silica. The mobile phase is generally an organic solvent such as hexane, heptane, dichloromethane or ethyl acetate.

TLS Online TPP Program

#Id: 2804

#Unit 13. Methods in Biology

In NPLC solvents form an elutropic series based on their polarity. Such a series in

TLS Online TPP Program

#Id: 2805

#Unit 13. Methods in Biology

 In NPLC order of elution of analytes is such that the least polar is eluted first and the most polar last.

TLS Online TPP Program

#Id: 2806

#Unit 13. Methods in Biology

The main applications of normal-phase liquid chromatography are its use to separate

analytes that have low water solubility and those that are not amenable to reversed phase liquid chromatography.