title: Influence of packaging material on the liquid stability of interferon-alpha2b.
abstract: OBJECTIVE
  In this article we studied the effect of the packaging material on the liquid stability of interferon alpha 2b (rhIFN-alpha2b).
  
  
  METHODS
  The compatibility of this cytokine with type I borosilicate glass ampoules was evaluated by ELISA and RP-HPLC, at 4 degrees C and after heat sealing. Additionally, the influence of protein concentration (3 and 10 MIU/ml), buffer species (sodium phosphate, sodium citrate and sodium citrate-phosphate) and additives (polysorbate 80 and EDTA Na(2) x 2H(2)O) were studied in samples with and without contact with chlorobutyl stoppers by RP-HPLC.
  
  
  RESULTS
  The compatibility of this cytokine in sodium phosphate buffer, with type I borosilicate glass ampoules showed a significant adsorption at the lowest concentration. This influence was eliminated with a polysorbate 80/benzyl alcohol-based vehicle. The effect of the heat sealing of ampoules on the stability of rhIFN-alpha2b showed two degradation peaks when a volume of 1 ml was dispensed. However, with a lower (0.5 ml) volume, the degradation was not detected. On the other hand, samples in contact with chlorobutyl stoppers increased the apparent degradation rate constant in the range of 6.74 +/- 0.38 to 46.34 +/- 3.11 x 10(3) day-(1). This effect significantly decreased in about 1.2- and 1.1-fold when sodium citrate or sodium citrate-phosphate buffers, respectively, were evaluated. Results from the evaluation of EDTA Na(2) x 2H(2)O or polysorbate 80 showed a similar behavior. These additives reduced the apparent degradation rate constant in the range of 2.01 +/- 0.14 to 25.51 +/- 3.57 x 10(3) day-(1).
  
  
  CONCLUSIONS
  The adsorption of the cytokine to type I borosilicate glass ampoules was eliminated with a polysorbate 80/benzyl alcohol-based vehicle, and the deleterious effect of the heat sealing decreased with a lower (0.5 ml) volume. Experimental data indicated that the contact with chlorobutyl stoppers accelerates the degradation of rhIFN-alpha2b. However, protein concentration, buffer species and pharmaceutical excipients can modulate this effect.
authors.affiliation: Formulation Development Department, Center for Genetic, Engineering and Biotechnology (CIGB), P.O. Box 6162, Havana, Cuba. llamil.ruiz@cigb.edu.cu
authors.forename: Llamil
authors.initials: L
authors.lastname: Ruiz
authors.forename: Nuria
authors.initials: N
authors.lastname: Reyes
authors.forename: Kethia
authors.initials: K
authors.lastname: Aroche
authors.forename: Vivian
authors.initials: V
authors.lastname: Tolosa
authors.forename: Vladimir
authors.initials: V
authors.lastname: Simanca
authors.forename: Teresa
authors.initials: T
authors.lastname: Rogríguez
authors.forename: Eugenio
authors.initials: E
authors.lastname: Hardy
mesh_terms: D000042:Absorption; D004349:Drug Packaging / Q000379:methods*; D004355:Drug Stability; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000032:analysis* / Q000737:chemistry*; D019999:Pharmaceutical Solutions / Q000737:chemistry; D011994:Recombinant Proteins
chemical_list: D000077190:Interferon alpha-2; D016898:Interferon-alpha; D019999:Pharmaceutical Solutions; D011994:Recombinant Proteins