title: Formulation, in vitro and in vivo evaluation of halofantrine-loaded solid lipid microparticles.
abstract: BACKGROUND
  Formulation, characterization, in vitro and in vivo evaluation of halofantrine-loaded solid lipid microparticles (SLMs).
  
  
  OBJECTIVE
  The objective of the study was to formulate and evaluate halofantrine-loaded SLMs.
  
  
  METHODS
  Formulations of halofantrine-loaded SLMs were prepared by hot homogenization and thereafter lyophilized and characterized using particle size, pH stability, loading capacity (LC) and encapsulation efficiency (EE). In vitro release of halofantrine (Hf) from the optimized SLMs was performed in SIF and SGF. In vivo study using Peter's Four day suppressive protocol in mice and the mice thereafter subjected to histological studies in kidney and liver.
  
  
  RESULTS
  Results obtained indicated that EE of 76.32% and 61.43% were obtained for the SLMs containing 7% and 3% of Hf respectively. The SLMs loaded with 3% of Hf had the highest yield of 73.33%. Time-dependent pH stability analysis showed little variations in pH ranging from 3.49 ± 0.04 to 4.03 ± 0.05.
  
  
  CONCLUSIONS
  The SLMs showed pH-dependent release profile; in SIF (43.5% of the drug for each of H2and H3) compared with SGF (13 and 18% for H2and H3respectively) after 8 h. The optimized SLMs formulation and Halfan® produced a percentage reduction in parasitemia of 72.96% and 85.71% respectively. The histological studies revealed that the SLMs formulations have no harmful effects on the kidney and liver.
  
  
  CONCLUSIONS
  SLMs formulations might be an alternative for patients with parasitemia as there were no harmful effects on vital organs of the mice.
authors.affiliation: a Drug Delivery Research Unit, Department of Pharmaceutics , University of Nigeria , Nsukka , Nigeria.
authors.forename: John D N
authors.initials: JDN
authors.lastname: Ogbonna
authors.affiliation: a Drug Delivery Research Unit, Department of Pharmaceutics , University of Nigeria , Nsukka , Nigeria.
authors.forename: Franklin C
authors.initials: FC
authors.lastname: Kenechukwu
authors.affiliation: a Drug Delivery Research Unit, Department of Pharmaceutics , University of Nigeria , Nsukka , Nigeria.
authors.forename: Chinekwu S
authors.initials: CS
authors.lastname: Nwobi
authors.affiliation: a Drug Delivery Research Unit, Department of Pharmaceutics , University of Nigeria , Nsukka , Nigeria.
authors.forename: Onochie S
authors.initials: OS
authors.lastname: Chibueze
authors.affiliation: a Drug Delivery Research Unit, Department of Pharmaceutics , University of Nigeria , Nsukka , Nigeria.
authors.forename: Anthony A
authors.initials: AA
authors.lastname: Attama
keywords: Hematological parameters; halofantrine; histological studies; parasitemia; solid–lipid microparticles