A novel set of behavioural indicators for measuring perception of food by cats.

Behavioural indicators provide a promising approach for objective assessment of the perceptions of animals. In cats, the frequency of specific behaviours as indicators of perception has been studied in connection with food palatability. The aim of this study was to expand that knowledge by identifying behavioural indicators correlating with three degrees of palatability.

Evaluating optimal combination of clodronate and bioactive glass for dental application.

Both clodronate and bioactive glass are mostly used alone as treatment in various bone diseases but, they are also known to have beneficial effects in dental application. The same processes that lead to loss of bone can also result in alveolar bone loss. The object of this study was to define the optimal combination of clodronate and bioactive glass (BAG) to be used locally in dentistry.

Interaction of bioactive glass with clodronate.

Bone tissue engineering is a rapidly growing area of research involving the use of bioactive glass (BG) alone and in combination with different materials. The objective of this study was to investigate the interaction of BG with clodronate. Characterisation of the interaction between BG and clodronate was undertaken using; scanning electron microscopy (SEM), X-ray powder diffraction (XRPD), Fourier transform Raman spectroscopy and Fourier transform infrared spectroscopy (FTIR).

Rapid particle size measurement using 3D surface imaging.

The present study introduces a new three-dimensional (3D) surface image analysis technique in which white light illumination from different incident angles is used to create 3D surfaces with a photometric approach. The three-dimensional features of the surface images created are then used in the characterization of particle size distributions of granules. This surface image analysis method is compared to sieve analysis and a particle sizing method based on spatial filtering technique with nearly 30 granule batches.

Granule size control and targeting in pulsed spray fluid bed granulation.

The primary aim of the study was to investigate the effects of pulsed liquid feed on granule size. The secondary aim was to increase knowledge of this technique in granule size targeting. Pulsed liquid feed refers to the pump changing between on- and off-positions in sequences, called duty cycles.

Effect of fluidisation activity on end-point detection of a fluid bed drying process.

The influence of inlet air humidity variations on fluid bed drying end-point detection was the primary focus here. Various drying end-point criteria based on temperature and humidity measurements were compared. Seasonally changing inlet air humidity affects the moisture content of the finished granules, as long as the drying process remains unchanged.

Novel description of a design space for fluidised bed granulation.

The physical measurements of a fluid bed granulator can be exploited in construction of an operating window, a design space, for process performance. The purpose of this study was to determine the influence of inlet air humidity changes on temperature in different parts of a granulator system, on fluidisation behaviour and on the particle size of the final granules. A humidifying setup was constructed on a bench-scale fluid bed granulator that enabled elevated humidity levels and sharp humidity changes of the inlet air.

Excipient selection can significantly affect solid-state phase transformation in formulation during wet granulation.

Phase transformations in formulations can lead to instability in physicochemical, biopharmaceutical, and processing properties of products. The influences of formulation design on the optimal dosage forms should be specified. The aim here was to investigate whether excipients with different water sorption behavior affect hydrate formation of nitrofurantoin in wet masses.

Role of water in the physical stability of solid dosage formulations.

The interaction of moisture with pharmaceutical solids is highly crucial to an understanding of water-based processes, for example, manufacturing processes or prediction of solid dosage form stability and shelf life. Both the active pharmaceutical ingredient (API) and excipients in the formulation have different moisture sorption properties that can result in unexpected processing-induced phase transitions and they can affect solid-state phase transitions in the final dosage forms. The character of excipient effects on the stability of formulation.

Characterization of polymorphic solid-state changes using variable temperature X-ray powder diffraction.

The aim of this study was to use variable temperature X-ray powder diffraction (VT-XRPD) to understand the solid-state changes in the pharmaceutical materials during heating. The model compounds studied were sulfathiazole, theophylline and nitrofurantoin. This study showed that the polymorph form of sulfathiazole SUTHAZ01 was very stable and SUTHAZ02 changed as a function of temperature to SUTHAZ01.

Role of excipients in hydrate formation kinetics of theophylline in wet masses studied by near-infrared spectroscopy.

Hydrate formation is a phase transition, which can occur during wet granulation. This kind of processing-induced transformation (PIT) can influence the quality of a finished product. The aim of the study was to investigate the effect of excipients on the kinetics of hydrate formation in wet masses.

Physical stability and moisture sorption of aqueous chitosan-amylose starch films plasticized with polyols.

The short-term stability and the water sorption of films prepared from binary mixtures of chitosan and native amylose maize starch (Hylon VII) were evaluated using free films. The aqueous polymer solutions of the free films contained 2% (w/w) film formers, glycerol, or erythritol as a plasticizer, as well as acetic acid (1%) and purified water. Characterization of the present fresh and conditioned film formers and free films was done using X-ray diffraction analysis, determination of moisture sorption isotherms, and near infrared spectroscopy.

Comparison of the effects of two drying methods on polymorphism of theophylline.

Processing-induced transformations in drug formulation may induce adverse biopharmaceutical changes in the finished product. During the drying phase of wet granulation, theophylline monohydrate transforms either the stable (form I), or a polymorphic, metastable (form I(*)) form of anhydrous theophylline. We investigated the effect of two drying methods (multichamber microscale fluid bed dryer MMFD) or variable temperature X-ray powder diffractometer (VT-XRPD) on the relative amounts of the different theophylline forms remaining in the dried granules.

Effects of excipients on hydrate formation in wet masses containing theophylline.

Transformations between solid phases in dosage forms can lead to instability in drug release. Thus, it is important to understand mechanisms and kinetics of phase transformations and factors that may influence them. During wet granulation theophylline shows pseudopolymorphic changes that may alter its dissolution rate.