Methemoglobin (Hb-M) is a rare hemoglobinopathy in China. We hereby report on a family living in Yantai, East China, with congenital cyanosis due to Hb-M mutation. The proband, a 65-year-old female, presented 63% oxygen saturation. Both Hb-M concentration and arterial oxygen saturation remained unchanged, even following intravenous treatment with methylene blue. There was also no change in blood-color (chocolate-brown) after adding 0.1% KCN. A fast-moving band (Hb-X) in hemolysates was found by cellulose acetate electrophoresis, the Hb-X/Hb-A ratio exceeding 10%. GT transition at 131nt of exon 2, although present in one of the α2-globin alleles, was not found in α1-globin alleles as a whole. This mutation leads to the aspartic acid to tyrosine substitution (Asp76Tyr). In this family, the novel mutation in the α2-globin gene resulted in a rare form of congenital cyanosis due to Hb-M. This hemoglobin was named Hb-M Yantai.

Um método empregando "bulk liquid membrane" (BLM) e o complexo ácido di(2-etilhexil) fosfórico (D2EHPA) e ácido O,O'-dibenzoil-(2R, 3R)-tartárico (L-(-)-DBTA) foi desenvolvido para a separação por extração do ácido mandélico racêmico (rac MA). Os efeitos de tempo de resolução, concentração de D2EHPA na fase orgânica, concentração de rac MA na fase doadora, velocidade de agitação e temperatura sobre a separação por extração foram estudados. Os resultados experimentais evidenciaram que o maior fator de separação (α) 2,74 e o valor do excesso enantiomérico (ee, %) 46,47% foram obtidos quando o tempo de resolução foi de aproximadamente 4 h, a razão de concentração molar de rac MA, D2EHPA e L-(-)-DBTA foi 0,05:0,2:0,3, a velocidade de agitação, 400 r min-1 e a temperatura, 35 ºC. O método desenvolvido é útil para a otimização do transporte de sistemas BLM e para a produção em grande escala de enantiômero puro.

A method of bulk liquid membrane (BLM) using complex of di(2-ethylhexyl) phosphoric acid (D2EHPA) and O,O'-dibenzoyl-(2R, 3R)-tartaric acid (L-(-)-DBTA) was developed for the extractive resolution of racemic mandelic acid (rac MA). The effects of resolution time, concentration of D2EHPA in the organic phase, concentration of rac MA in the feed phase, stirring speed and temperature on extractive resolution were studied. The experimental results have shown that the greatest separation factor (α) 2.74 and the enantiomeric excess value (ee, %) 46.47% were obtained when the resolution time was about 4 h, the molar concentration ratio of rac MA, D2EHPA and L-(-)-DBTA 0.05:0.2:0.3, the stirring speed 400 r min-1 and the temperature 35 ºC. The developed method is helpful for optimizing the transport of BLM systems and for large-scale production of pure enantiomer.