> -----Original Message-----
> From: fperini@unmc.edu [SMTP:fperini@unmc.edu]
> Sent: Thursday, September 23, 1999 12:59 PM
> To: Recipients of ABRF List
> Subject: D,L-amino acids
>
> About two months ago there were two requests for D,L-amino acid
> separations.I had done
> some work in the past,but with cumbersome methods,but I was
> interested,since,at times,I have
> had to analyze peptides with D-amino acids
> I found two types of analyses in the literature,one making use of the
> Marfey's reagent and
> the other of precolumn OPA-N-Ac-Cys.I had tried the latter with some
> success.
> The Marfey's worked but it was limited to a few amino acids,as
> reported.The
> OPA method,
> according to Nimura and Kinoshita:J.of Chromat.352,169-177(1986) had
> worked
> in the
> author's hands very well.Only D and L-Lys did not resolve.I tried several
> columns,since the
> one listed ,Devolosil ODS,was not available.They,also,used methanol,which
> gave me back
> pressures of over 3000 psi.,at a lower flow rate.
> I tried acetonitrile,and I got extremely sharp peaks with an old
> Ultrasphere column.There was
> some resolution,but not enough if the percent of D-a.a. was low,as
> expected.,for S,A,L and K.
> All other amino acids resolve well,but a few overlapped.So,this method may
> work with the right column,or if not all amino acids are present.Has
> anyone
> else done better?
>
>
> Fulvio Perini,Ph.D.
> 986805 Nebraska Med.Cnrtr.
> Omaha,NE 68198-6805
> ph:402-559-6184/FAX 402-559-4651
> fperini@unmc.edu
>