High Performance LC
	ReproSil 100 Chiral-AA, 8 µm ReproSil Chiral-AA is specially designed for the chiral separation of underivatized Amino Acids. This phase shows also a good selectivity towards Oxazolidinones, Hydantoins, Diazepines and Sulfoxides. It is based on the ultrapure Reprosil 100 silica. The chiral selector, an aromatic compound, is covalently bound to an 8 µm silica.
	Reprosil Chiral-AA is a so called brush-type phase like the other chiral Reprosil phases: -Reprosil Chiral-NR: With a very broad generality for aromatic compounds with an Oxygen (Nitrogen) near the chiral centre. For Normal- and Reversed phases separations. -Reprosil Chiral-OH: for aromatic compounds with an OH-group on the chiral centre -Reprosil Chiral-CA for aromatic compounds with a Carboxylic Acid group and -Reprosil Chiral-PS for aromatic compounds, which contain S or P atoms. Due to the 100A° pores and the big surface area of 350 m2/g the phase has an excellent preparative capacity. With a 250 x 10 mm column one can separate 50 – 250 mg / injection and with a 250 x 20 mm column 250 – 1000 mg/ injection. The phase is stable in all commonly used HPLC eluents. Typical eluents for neutral Amino acids are mixtures of ACN/ H20 (50/50) or MeOH / H20 (50/50), for acidic amino acids (MeOH / H20 / formic acid ( 50 / 50 / 0,2) and for basic amino acids MeOH / 20 mM Ammonium Acetate pH4.1 (50/50). The best pH-range is between 2 und 7. The columns are stable up to 300 bar. Examples for separations: The typical column dimension is 250 x 4.6 mm with a flow of 1 or 2 ml / min.     Amino acids:                   Compound: Eluent: Auflösung (Rs)     Alanine ACN/ H20 (50/50) 4.0     Arginine MeOH / H20/Amm. Acetate, pH4.1 3.0     Aspartic MeOH / H20/Amm. Acetate, pH4.1 2.0     Asparagine MeOH / H20/Formic acid (50/50/0.02) 3.7     Cysteine ACN/ H20 (50/50) 1.8     Glutamic MeOH / H20/Formic acid (50/50/0.02) 2.5     Glutamine MeOH / H20/Amm. Acetate, pH4.1 3.5     Histidine MeOH / H20/Amm. Acetate, pH4.1 1.5     Isoleucine ACN/ H20 (50/50) 3.0     Leucine ACN/ H20 (50/50) 5.5     Lysine MeOH / H20/Amm. Acetate, pH4.1 2.5     Methinone ACN/ H20 (50/50) 3.5     Phenylalanine ACN/ H20 (50/50) 7.2     Proline ACN/ H20 (50/50) 6.2     Serine ACN/ H20 (50/50) 1.9     Threonine ACN/ H20 (50/50) 4.0     Tyrosine ACN/ H20 (50/50) 2.9     Tryptophan ACN/ H20 (50/50) 3.5     Valine ACN/ H20 (50/50) 4.5               Examples for separation of Amino acids: (The L-form elutes first for all cases)                    back