TY - JOUR
T1 - The influence of physical properties and morphology of crystallised lactose on delivery of salbutamol sulphate from dry powder inhalers
AU - Kaialy, Waseem
AU - Martin, Gary P.
AU - Larhrib, Hassan
AU - Ticehurst, Martyn D.
AU - Kolosionek, Ewa
AU - Nokhodchi, Ali
PY - 2012/1/1
Y1 - 2012/1/1
N2 - The aim of this work was to investigate the mechanistic evaluation of physicochemical properties of new engineered lactose on aerosolisation performance of salbutamol sulphate (SS) delivered from dry powder inhaler (DPI). Different crystallised lactose particles were obtained from binary mixtures of butanol:acetone. The sieved fractions (63-90μm) of crystallised lactose were characterised in terms of size, shape, flowability, true density and aerosolisation performance (using multiple twin stage impinger (MSLI), Aerolizer ® inhaler device, and salbutamol sulphate as a model drug). Compared to commercial lactose, crystallised lactose particles were less elongated, covered with fine lactose particles, and had a rougher surface morphology. The crystallised lactose powders had a considerably lower bulk and tap density and poorer flow when compared to commercial lactose. Engineered carrier with better flow showed improved drug content homogeneity, reduced amounts of drug " deposited" on the inhaler device and throat, and a smaller drug aerodynamic diameter upon inhalation. Aerodynamic diameter of salbutamol sulphate increased as lactose aerodynamic diameter decreased (linear, R 2=0.9191) and/or as fine particle lactose content increased (linear, R 2=0.8653). Improved drug aerosolisation performance in the case of crystallised lactose particles was attributed to lower drug-carrier adhesion forces due to a rougher surface and higher fine particle content. In conclusion, this work proved that using binary combinations of solvents in crystallisation medium is vital in modification of the physicochemical and micromeritic properties of carriers to achieve a desirable aerosolisation performance from DPI formulations. Among all lactose samples, lactose particles crystallised from pure butanol generated the highest overall DPI formulations desirability.
AB - The aim of this work was to investigate the mechanistic evaluation of physicochemical properties of new engineered lactose on aerosolisation performance of salbutamol sulphate (SS) delivered from dry powder inhaler (DPI). Different crystallised lactose particles were obtained from binary mixtures of butanol:acetone. The sieved fractions (63-90μm) of crystallised lactose were characterised in terms of size, shape, flowability, true density and aerosolisation performance (using multiple twin stage impinger (MSLI), Aerolizer ® inhaler device, and salbutamol sulphate as a model drug). Compared to commercial lactose, crystallised lactose particles were less elongated, covered with fine lactose particles, and had a rougher surface morphology. The crystallised lactose powders had a considerably lower bulk and tap density and poorer flow when compared to commercial lactose. Engineered carrier with better flow showed improved drug content homogeneity, reduced amounts of drug " deposited" on the inhaler device and throat, and a smaller drug aerodynamic diameter upon inhalation. Aerodynamic diameter of salbutamol sulphate increased as lactose aerodynamic diameter decreased (linear, R 2=0.9191) and/or as fine particle lactose content increased (linear, R 2=0.8653). Improved drug aerosolisation performance in the case of crystallised lactose particles was attributed to lower drug-carrier adhesion forces due to a rougher surface and higher fine particle content. In conclusion, this work proved that using binary combinations of solvents in crystallisation medium is vital in modification of the physicochemical and micromeritic properties of carriers to achieve a desirable aerosolisation performance from DPI formulations. Among all lactose samples, lactose particles crystallised from pure butanol generated the highest overall DPI formulations desirability.
KW - Carrier
KW - Dry powder inhaler
KW - Inhalation efficiency
KW - Lactose crystallisation
KW - Morphology
KW - Non-solvent
UR - http://www.scopus.com/inward/record.url?scp=80054988878&partnerID=8YFLogxK
U2 - 10.1016/j.colsurfb.2011.08.019
DO - 10.1016/j.colsurfb.2011.08.019
M3 - Article
C2 - 21962946
AN - SCOPUS:80054988878
VL - 89
SP - 29
EP - 39
JO - Colloids and Surfaces B: Biointerfaces
JF - Colloids and Surfaces B: Biointerfaces
SN - 0927-7765
IS - 1
ER -