Dear Jacob,
Please check the following references:
http://www.ncbi.nlm.nih.gov/pubmed/8771063
http://www.ncbi.nlm.nih.gov/pubmed/9251095
From some limited reading of another paper, it seems like the dark solution could be the conversion of L-Dopa into melanin, which is accelerated in alkaline conditions. The authors were extracting L-Dopa from beans and showed that 3>pH<5 was ideal for maximizing solubility of L-Dopa in solution. They suggested citric acid from fruit juice (Lemon, 10mL/L) for extraction/solubilization of L-Dopa. (www.redalyc.org/pdf/939/93911288017.pdf)
Good luck!
Bryan
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-----Original Message-----
From: CCP4 bulletin board [mailto:[log in to unmask]] On Behalf Of Keller, Jacob
Sent: Thursday, July 03, 2014 1:35 PM
To: [log in to unmask]
Subject: [ccp4bb] L-Dopa Stabilization?
Dear Crystallographers,
Does anyone have experience with co-crystallization of a protein with L-Dopa? In my hands, the L-Dopa degrades in water to a dark solution within 10 minutes. I am thinking of trying some reductants and metal chelation, but a verified successful formula would be much appreciated, and preferably it would be without going into a glove box.
Jacob Keller
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Jacob Pearson Keller, PhD
Looger Lab/HHMI Janelia Farms Research Campus
19700 Helix Dr, Ashburn, VA 20147
email: [log in to unmask]
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