Lactose and thermal analysis with special emphasis on microcalorimetry

Assessment of amorphous content by microcalorimetry

“…42 J/g. These observations were consistent with those of earlier studies using lactose, and the obtained heat¯ow was a little larger than that reported by Angberg 18 but nearly consistent with that reported by Buckton et al 16,17,21 Next, we mixed the amorphous with the crystalline form at various ratios and subjected the mixtures to the same measurement. The relationship between the amorphous content calculated from the mixing ratio and that from the microcalorimetric measurements is shown in Figure 1.…”

An investigation into lactose crystallization under high temperature conditions during spray drying

“…A large amount of work exists in the literature on the thermal analysis of pure lactose and its different anomers and polymorphs (Angberg, 1995;Berlin, Kliman, Anderson, & Pallansch, 1971;Drapier-Beche, Fanni, & Parmentier, 1999;Drapier-Beche, Fanni, Parmentier, & Vilasi, 1997;Gombás, Szabó-Révész, Kata, Regdon, & Erõs, 2002;Lerk et al, 1984;Listiohadi et al, 2009;Naini, Byron, & Phillips, 1998;Sebhatu, Elamin, & Ahlneck, 1994;Sebhatu et al, 1994;Steckel & Bolzen, 2005 The reported thermal transitions of different form of lactose during DSC analysis include the following ones:…”

“…Moreover, Angberg (1995) suggested that anhydrous a-and b-lactose both transform to a-lactose monohydrate when exposed to water vapour; but b-lactose must first mutarotate to a-lactose, which is a rate-limiting process. Both these studies suggest that the initial b-anomer present in the collection vessel sample mutarotated to a-anomer, and at the same time this new a-anomer crystallized.…”

Excipient Selection in Oral Solid Dosage Formulations Containing Moisture Sensitive Drugs

“…Nuclear magnetic resonance (NMR) and FT Raman spectroscopy Nuclear magnetic resonance spectra Mobility of water molecules in a system Khan and Pilpel 1987;Martinez et al 1990;Suryanarayanan and Wiedmann 1990;Yoshioka et al 1992Yoshioka et al , 1995Aso et al 1994Aso et al , 1997Taylor et al 2001;McCrystal et al 2002;Suzuki and Kawasaki 2005 Strength of the hydrogen bonds with water Determination of plasticizing effect of water on polymer mobility, differentiation between samples in rubbery and glassy state Pikal et al 1977;Hollenbeck et al 1978;Angberg et al 1988Angberg et al , 1990Angberg et al , 1991Angberg et al , 1992aAngberg et al , 1992bFielden et al 1988;Buckton andBeezer, 1988, 1991;Pikal and Dellerman 1989;Blair et al 1990;Angberg 1995;Pudipeddi et al 1996;Buckton 2000 …”

“…the rate of heat production, with a sensitivity of about 10 4 greater than it is possible with a conventional DSC (Pikal and Dellerman 1989). In a series of publications (Angberg et al 1988(Angberg et al , 1990(Angberg et al , 1991(Angberg et al , 1992aAngberg 1995), the use of heat-conduction microcalorimetry in pharmaceutical stability studies was evaluated. The authors showed that, with the help of microcalorimetry, it was possible to detect the hydration process of anhydrous lactose after only one day of storage at 58 % RH.…”