Badal Tejedor, Maria, Nordgren, Niklas, Rutland, Mark, Schuleit, Michael, Millqvist-Fureby, Anna, Alderborn, Goran and Pazesh, Samaneh (2017) Determination of Interfacial Amorphicity in Functional Powders. Langmuir the ACS journal of surfaces and colloids., 33 (33). pp. 920-926. ISSN 1520-5827; 0743-7463

Abstract

Milling of pharmaceutical ingredients is a common manufacturing step before tableting that involves high energy loads which may lead to material amorphisation. Changes on the surface structure of the material will likely impact the flow properties, dissolution rate and tabletabity of the powder blend. Therefore it is important to measure and control the level of amorphicity induced after milling. Several characterization techniques have been used to determine the amorphous content of a processed material. However, the possibility to characterize the mechanical properties of the particles’ surface at the nanoscale, it is only offered by Atomic Force Microscopy (AFM). AFM PeakForce QNM technique has been used to measure the variation in energy dissipation (eV) at the surface of the particles which shed light on the mechanical changes occurring as a result of the amorphisation events. In order to develop a methodology to detect particle surface amorphicity, α-lactose monohydrate was evaluated prior milling, after 1 h milling and after spray-drying. Higher and lower energy dissipative values were measured for spray-dried and unprocessed lactose respectively. 1 h milled lactose sample presented an intermediate behavior between the crystalline and the amorphous structure indicating induced surface modification during the milling process. Visual evaluation of the lactose samples was done with AFM and SEM showing significant topographical differences. The crystallization event of the 1 h milled lactose was followed with both AFM and SEM that corroborates the presence of amorphous material on the surface of the milled lactose.

Item Type:	Article
Keywords:	surface characterisation, excipients,surface mechanical properties, atomic force microscopy, amorphicity
Date Deposited:	08 Apr 2017 00:45
Last Modified:	08 Apr 2017 00:45
URI:	https://oak.novartis.com/id/eprint/30804