title: Characterization and selection of suitable grades of lactose as functional fillers for capsule filling: part 1.
abstract: The purpose of this work is to characterize thermal, physical and mechanical properties of different grades of lactose and better understand the relationships between these properties and capsule filling performance. Eight grades of commercially available lactose were evaluated: Pharmatose 110 M, 125 M, 150 M, 200 M, 350 M (α-lactose monohydrate), AL (anhydrous lactose containing ∼80% β-AL), DCL11 (spray dried α-lactose monohydrate containing ∼15% amorphous lactose) and DCL15 (granulated α-lactose monohydrate containing ∼12% β-AL). In this study, different lactose grades were characterized by thermal, solid state, physical and mechanical properties and later evaluated using principal component analysis (PCA) to assess the inter-relationships among some of these properties. The lactose grades were characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), moisture sorption/desorption isotherms, particle size distribution; the flow was characterized by Carr Index (CI), critical orifice diameter (COD) and angle of friction. Plug mechanical strength was estimated from its diametric crushing strength. The first and second principal components (PC) captured 47.6% and 27.4% of variation in the physical and mechanical property data, respectively. The PCA plot grouped together 110 M, AL, DCL11 and DCL15 on the one side of plot which possessed superior properties for capsule formulation and these grades were selected for future formulation development studies (part II of this work).
authors.affiliation: a School of Pharmacy , University of Maryland , Baltimore , MD , USA .
authors.forename: Vikas
authors.initials: V
authors.lastname: Moolchandani
authors.forename: Larry L
authors.initials: LL
authors.lastname: Augsburger
authors.forename: Abhay
authors.initials: A
authors.lastname: Gupta
authors.forename: Mansoor
authors.initials: M
authors.lastname: Khan
authors.forename: John
authors.initials: J
authors.lastname: Langridge
authors.forename: Stephen W
authors.initials: SW
authors.lastname: Hoag
mesh_terms: D002152:Calorimetry, Differential Scanning; D002214:Capsules; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D004339:Drug Compounding / Q000379:methods*; D005079:Excipients / Q000737:chemistry*; D007785:Lactose / Q000737:chemistry*; D010316:Particle Size; D025341:Principal Component Analysis; D013818:Thermogravimetry; D014961:X-Ray Diffraction
chemical_list: D002214:Capsules; D005079:Excipients; D007785:Lactose
keywords: capsule filling; filler characterization; plug mechanical strength; α-Lactose monohydrate; β-anhydrous lactose