HemoCD as a Totally Synthetic Artificial Oxygen Carrier: Improvements in the Synthesis and O2/CO Discrimination

• Published in: Artificial organs Vol. 41; no. 4; pp. 372 - 380
• Main Authors: Kitagishi, Hiroaki, Mao, Qiyue, Kitamura, Naoya, Kita, Takahiro
• Format: Journal Article
• Language: English
• Published: Geesthacht Wiley Subscription Services, Inc 01.04.2017
• Subjects: Ambient temperature; Aqueous solutions; Artificial oxygen carrier; Cyclodextrin; Discrimination; Hemoglobin; Iron; Oxygen; Porphyrin; Pyridines; Selectivity; Synthesis; Temperature effects
• ISSN: 0160-564X; 1525-1594
• DOI: 10.1111/aor.12870

HemoCD, which is composed of an iron(II)porphyrin such as 5,10,15,20‐tetrakis(4‐sulfonatophenyl)porphinatoiron(II) (Fe(II)TPPS) and a cyclodextrin (CD) dimer having a pyridine linker, represents a synthetic hemoglobin (Hb) model compound that exhibits reversible oxygen (O2) binding ability in aqueous solution at an ambient temperature. Therefore, hemoCD has the potential to be used as a totally synthetic artificial oxygen carrier. In this article, we describe the improvements of hemoCD related to its synthesis and O2/CO selectivity. The synthesis procedure of the CD dimer of hemoCD was re‐examined, and the CD dimer was successively synthesized from inexpensive β‐CD with a 38% yield (three‐steps), which enabled us to obtain the CD dimer in gram‐quantities. The O2/CO selectivity of hemoCD was also markedly improved using an iron(II)porphyrin having a carboxylate group at the distal site of hemoCD.