title: Could albumin affect the self-assembling properties of a block co-polymer system and drug release? An in-vitro study.
abstract: OBJECTIVE
  This work investigated the influence of a model protein, bovine serum albumin (BSA), on the properties of a thermogelling formulation intended for administration inside body compartments where there is high albumin content, as in the case of inflamed joints; it also explored the relation between the variation of these properties and release performance of methotrexate (MTX), a drug used to treat forms of arthritis and rheumatic conditions.
  
  
  METHODS
  The influence of BSA on the micellisation and gelation behaviour of Poloxamer 407, chosen as a model copolymer, was studied by differential scanning calorimetry (microDSC), dynamic light scattering (DLS), fluorescence spectroscopy and rheology studies. A release study of MTX loaded inside the hydrogel in presence and in absence of BSA was performed.
  
  
  RESULTS
  DLS and microDSC data revealed that the micellisation process was not affected by the protein, as demonstrated by unaltered micellar size and thermodynamic parameters. While the presence of BSA in the copolymer system reduced gel consistency, the hydrogel release performance was only slightly affected.
  
  
  CONCLUSIONS
  Our results suggested that the kinetics of MTX release mainly depended on the presence of the thermogelling copolymer, although other mechanisms related to BSA could be involved. Finally, the study assessed the feasibility of using a thermogelling hydrogel for in situ drug administration in areas with the presence of high protein concentrations.
authors.affiliation: School of Pharmacy, University of Camerino, Camerino, MC, Italy.
authors.forename: Diego R
authors.initials: DR
authors.lastname: Perinelli
authors.forename: Giulia
authors.initials: G
authors.lastname: Bonacucina
authors.forename: Stefania
authors.initials: S
authors.lastname: Pucciarelli
authors.forename: Marco
authors.initials: M
authors.lastname: Cespi
authors.forename: Luca
authors.initials: L
authors.lastname: Casettari
authors.forename: Valeria
authors.initials: V
authors.lastname: Polzonetti
authors.forename: Francesco Martino
authors.initials: FM
authors.lastname: Carpi
authors.forename: Giovanni F
authors.initials: GF
authors.lastname: Palmieri
mesh_terms: D018501:Antirheumatic Agents / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D002626:Chemistry, Pharmaceutical; D004337:Drug Carriers; D020100:Hydrogels; D007700:Kinetics; D008027:Light; D008727:Methotrexate / Q000737:chemistry*; D008823:Micelles; D008956:Models, Chemical; D015394:Molecular Structure; D010316:Particle Size; D020442:Poloxamer / Q000737:chemistry*; D012212:Rheology; D012542:Scattering, Radiation; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D012995:Solubility; D013050:Spectrometry, Fluorescence; D013329:Structure-Activity Relationship; D013678:Technology, Pharmaceutical / Q000379:methods; D013696:Temperature
chemical_list: D018501:Antirheumatic Agents; D004337:Drug Carriers; D020100:Hydrogels; D008823:Micelles; D020442:Poloxamer; D012710:Serum Albumin, Bovine; D008727:Methotrexate