BCH I EN1 Lab08-09

The mobile phase:

• is fixed on a solid support material

• is represented by a fluid

• is one of the components of the electrophoretic system

In adsorption chromatography:

• separation is based on the polarity of the analytes

• the stationary phase is an ion-exchange resin

• the analyte that is adsorbed the strongest on the stationary phase elutes the fastest

Choose the correct statement:

• ion exchange chromatography: the anion is a resin with a negative charge

• partition chromatography: the analyte that has the same polarity as the mobile phase elutes faster

• size exclusion chromatography: the analyte larger than the pores of the gel spends more time in the chromatographic system

Paper chromatography:

• is a type of ion exchange chromatography

• is a type of planar chromatography

• is a type of chromatography where separation is based on size

In the separation of amino acids using paper chromatography:

• polar amino acids migrate faster

• the stationary phase is represented by -OH cellulose groups + H₂O

• histidine migrates more than phenylalanine

The retention factor in paper chromatography:

• is greater the more the analyte migrates

• has a value close to 1 if the analyte has an affinity for the stationary phase

• is calculated as the ratio of the solvent front to the distance traveled by the analyte

Ninhydrin:

• reacts with the COOH groups of amino acids

• negatively charges proteins

• generates a violet compound upon heating

In dialysis:

• ions migrate through the semipermeable membrane from low concentration to high concentration

• the solvent traverses the semipermeable membrane from low concentration to high concentration

• proteins pass through the semipermeable membrane from high concentration to low concentration

In hemodialysis:

• the semipermeable membrane is biological

• the separation is extracorporeal

• the patient can carry out daily activities during the procedure

After dialysis of a mixture of Albumin and (NH₄)₂SO4:

• the two ions can be found in the dialysis bag

• the identification of the ammonium ion is done with Biuret reagent

• the presence of protein is confirmed by the appearance of a white precipitate