title: Low density lipoprotein adsorption on sol-gel derived alumina for blood purification therapy.
abstract: Among the clinical treatments of Familial Hyper cholesterolemia patients to reduce the concentration of low density lipoprotein (LDL), blood purification therapy is most suitable in which a blood-compatible adsorbent is employed. In the present study, alumina powders were prepared via a sol-gel route to develop a LDL-adsorbent Aluminum tri2-propoxide was hydrolyzed and subsequently calcined up to 1200 degrees C. Surface charge density and pore size distribution were measured, and the phases were identified. The alumina calcined above 400 degrees C had excellent blood compatibility in terms of endogenous clotting parameters, i.e., partial thromboplastin time: (PTT), prothrombin time: (PT), and the amount of fibrinogen: (Fib). The amount of LDL-adsorption (DeltaW(LDL)) increased with the calcining temperature, showing a good linear correlation to surface charge density. The 1200 degrees C sample consisted only of alpha-alumina, and was greatest in DeltaW(LDL). All samples involved pores smaller than 20 nm but not the pores large enough to accommodate LDL molecules (20-25 nm). From those results, it was concluded for the present alumina particles that the surface charge density was the primary factor and that the chemical activity of alpha-alumina also contributed to the excellent LDL-adsorption for the 1200 degrees C sample, while entrapping LDL in the pores was not an active mechanism.
authors: Graduate School of Natural Sciences and Technology, Okayama University, Tsushima, Okayama, Japan. takuji.asano@nikkiso.co.jp
authors: Takuji
authors: T
authors: Asano
authors: Kanji
authors: K
authors: Tsuru
authors: Satoshi
authors: S
authors: Hayakawa
authors: Akiyoshi
authors: A
authors: Osaka
mesh_terms: D000327:Adsorption; D000328:Adult; D000537:Aluminum Oxide / Q000138:chemical synthesis / Q000737:chemistry* / Q000627:therapeutic use*; D001781:Blood Component Removal / Q000379:methods*; D008078:Cholesterol, LDL / Q000097:blood / Q000302:isolation & purification* / Q000493:pharmacokinetics*; D005340:Fibrinogen / Q000302:isolation & purification; D005782:Gels / Q000737:chemistry / Q000627:therapeutic use; D006801:Humans; D006950:Hyperlipidemia, Familial Combined / Q000097:blood / Q000628:therapy; D007202:Indicators and Reagents / Q000302:isolation & purification; D010316:Particle Size; D044367:Phase Transition; D016062:Porosity; D055672:Static Electricity
chemical_list: D008078:Cholesterol, LDL; D005782:Gels; D007202:Indicators and Reagents; D005340:Fibrinogen; D000537:Aluminum Oxide