Direct compression has gained significant interest since its advent in the late 1950's due to its potential ease compared to wet granulation. The primary prerequisites for powders used in direct compression are (i) good flow properties (ii) good compressibility and (iii) an acceptable dilution potential to accommodate a relative high percentage of active ingredient. Several filler/binders have been manufactured especially for direct compression and co–processing is one of the recent methods used to produce good compressible excipients with acceptable flow properties. In this study, lactose–based filler/binders were used which included simple and modified lactose materials (Granulac, Lactopress, Flowlac and Tablettose) as well as co–processed excipients (Starlac, Cellactose and Microcelac). A comprehensive literature study on direct compression revealed the importance of the physical properties of filler/binders such as interparticle forces, particle shape, particle size and distribution, powder density, particle surface structure and particle packing geometry which influence the flow of powders. All the materials were subjected to the various tests available to evaluate powder flow, namely (i) angle of repose (AoR), (ii) critical orifice diameter (COD), (iii) flow rate and percentage compressibility (%C) in terms of the powders' bulk and tap densities. The results of these tests confirmed the expected flow properties of the various filler/binders, with only one material exhibiting extremely poor flow properties. The following rank order in terms of all flow tests conducted was established; Starlac >> Microcelac ~ Flowlac >> Cellactose > Tablettose > Lactopress >>> Granulac. The co–processed filler/binders presented with superior flow compared to the other lactose–based materials. During the next phase of the study, the compaction properties of the various fillers were evaluated, employing direct compression. Compacts of pure filler were tabletted on an eccentric tablet press at different compression pressures (manipulated by the upper punch setting of the tablet press). The modified lactose filler/binders (Lactopress, Flowlac and Tablettose) exhibited unexpectedly poor compression profiles, where the co–processed filler/binders (Starlac, Cellactose and Microcelac) produced compacts with acceptable appearance and compact properties. Two lubricants (Mg–St or Pruv), which were tested separately in formulations were added since no compacts could be produced from the pure filler/binders. None of the modified lactose filler/binders, in combination with a lubricant, were able to produce an acceptable compact, since lamination occurred during compression. The co–processed filler/binders produced satisfactory compacts with the addition of a lubricant, but lactose–cellulose fillers (Cellactose and Microcelac) also required the inclusion of a disintegrant (Ac–Di–Sol) to induce satisfactory compact disintegration. Poor compressible active ingredients (paracetamol), which exhibit very poor flow properties, are usually difficult to use during direct compression. Many excipients (tested in this study) are formulated to accommodate these drugs and produce acceptable functional tablets. After identifying the best filler/binders (co–processed fillers), according to their flow and compressible properties, paracetamol was added to the formulations. During a pilot study, the percentage paracetamol these fillers could accommodate in a 400 mg tablet was determined. Both Microcelac and Cellactose could accommodate 24.5% w/w paracetamol, whilst Starlac could only accommodated 19.5% w/w. Paracetamol is well known for its tendency to cause tablet capping and lamination. An acceptable upper punch setting range (20–22) was chosen for tabletting, followed by quality control tests done. All three formulations produced suitable tablets for testing and exhibited good tablet properties. All tablets disintegrated within two minutes, with hardness profiles between 120 N and 148 N and friability percentages less than 1%. Dissolution studies, however, are probably the ultimate test to distinguish between the capability of filler/binders to release the optimum percentage drug after disintegration. Dissolution studies were done on all three formulations using the AUC (area under the curve) and IDR (initial drug release) as parameters to evaluate drug release. All tablets exhibited high initial dissolution rates (between 0.018 - 0.023 mg/min/ml) and 100% drug release was observed. Starlac presented with a lower amount of drug released compared to the other two, but can be explained by the lower percentage (19.5%) paracetamol present in the formulation. It was once again confirmed that the physical and compressible properties of potential directly compressible filler/binders play a major role in direct compression. It was concluded that co–processed filler/binders (Starlac, Microcelac and Cellactose) definitely exhibited better tabletting properties during direct compression. They were able to accommodate a certain percentage of paracetamol, although it was expected that they would accommodate a higher amount (at least 50% of total tablet weight). / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2011.

Direct compression has gained significant interest since its advent in the late 1950's due to its potential ease compared to wet granulation. The primary prerequisites for powders used in direct compression are (i) good flow properties (ii) good compressibility and (iii) an acceptable dilution potential to accommodate a relative high percentage of active ingredient. Several filler/binders have been manufactured especially for direct compression and co–processing is one of the recent methods used to produce good compressible excipients with acceptable flow properties. In this study, lactose–based filler/binders were used which included simple and modified lactose materials (Granulac, Lactopress, Flowlac and Tablettose) as well as co–processed excipients (Starlac, Cellactose and Microcelac). A comprehensive literature study on direct compression revealed the importance of the physical properties of filler/binders such as interparticle forces, particle shape, particle size and distribution, powder density, particle surface structure and particle packing geometry which influence the flow of powders. All the materials were subjected to the various tests available to evaluate powder flow, namely (i) angle of repose (AoR), (ii) critical orifice diameter (COD), (iii) flow rate and percentage compressibility (%C) in terms of the powders' bulk and tap densities. The results of these tests confirmed the expected flow properties of the various filler/binders, with only one material exhibiting extremely poor flow properties. The following rank order in terms of all flow tests conducted was established; Starlac >> Microcelac ~ Flowlac >> Cellactose > Tablettose > Lactopress >>> Granulac. The co–processed filler/binders presented with superior flow compared to the other lactose–based materials. During the next phase of the study, the compaction properties of the various fillers were evaluated, employing direct compression. Compacts of pure filler were tabletted on an eccentric tablet press at different compression pressures (manipulated by the upper punch setting of the tablet press). The modified lactose filler/binders (Lactopress, Flowlac and Tablettose) exhibited unexpectedly poor compression profiles, where the co–processed filler/binders (Starlac, Cellactose and Microcelac) produced compacts with acceptable appearance and compact properties. Two lubricants (Mg–St or Pruv), which were tested separately in formulations were added since no compacts could be produced from the pure filler/binders. None of the modified lactose filler/binders, in combination with a lubricant, were able to produce an acceptable compact, since lamination occurred during compression. The co–processed filler/binders produced satisfactory compacts with the addition of a lubricant, but lactose–cellulose fillers (Cellactose and Microcelac) also required the inclusion of a disintegrant (Ac–Di–Sol) to induce satisfactory compact disintegration. Poor compressible active ingredients (paracetamol), which exhibit very poor flow properties, are usually difficult to use during direct compression. Many excipients (tested in this study) are formulated to accommodate these drugs and produce acceptable functional tablets. After identifying the best filler/binders (co–processed fillers), according to their flow and compressible properties, paracetamol was added to the formulations. During a pilot study, the percentage paracetamol these fillers could accommodate in a 400 mg tablet was determined. Both Microcelac and Cellactose could accommodate 24.5% w/w paracetamol, whilst Starlac could only accommodated 19.5% w/w. Paracetamol is well known for its tendency to cause tablet capping and lamination. An acceptable upper punch setting range (20–22) was chosen for tabletting, followed by quality control tests done. All three formulations produced suitable tablets for testing and exhibited good tablet properties. All tablets disintegrated within two minutes, with hardness profiles between 120 N and 148 N and friability percentages less than 1%. Dissolution studies, however, are probably the ultimate test to distinguish between the capability of filler/binders to release the optimum percentage drug after disintegration. Dissolution studies were done on all three formulations using the AUC (area under the curve) and IDR (initial drug release) as parameters to evaluate drug release. All tablets exhibited high initial dissolution rates (between 0.018 - 0.023 mg/min/ml) and 100% drug release was observed. Starlac presented with a lower amount of drug released compared to the other two, but can be explained by the lower percentage (19.5%) paracetamol present in the formulation. It was once again confirmed that the physical and compressible properties of potential directly compressible filler/binders play a major role in direct compression. It was concluded that co–processed filler/binders (Starlac, Microcelac and Cellactose) definitely exhibited better tabletting properties during direct compression. They were able to accommodate a certain percentage of paracetamol, although it was expected that they would accommodate a higher amount (at least 50% of total tablet weight). / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2011.

Carbon-bonded alumina filters and their binders, lactose, tannin and CarboresP, were investigated by Raman spectroscopy. Special emphasis was placed on the pyrolysis study of the binders. In situ measurements were performed on the tannins gallic acid, ellagic acid and tannic acid to determine the pyrolysis temperatures and products. Furthermore, the binder samples fired in a reducing atmosphere in a coke bed were analyzed by Raman spectroscopy and their transition from an amorphous carbon system to nanocrystalline graphite was observed. The influence of different binders on the carbon-bound alumina filters was studied, as well as the influence of different additives. However, no significant difference was observed between samples with different binder compositions or with additives. In addition, Raman measurements on the spinel MgAlON indicate an increased disorder of the structure due to the incorporated nitrogen.

In den vorliegenden Untersuchungen wurde das Ziel verfolgt die Nutzbarkeit des Milchinhaltsstoffes Laktose als praxistaugliche Managementhilfe zu prüfen. Die Primärdaten stammen aus drei israelischen Hochleistungsherden, über mehrere Laktationen erhoben. Der Parameter Laktosegehalt wurde in der Datenaufbereitung dahingehend geprüft, ob dieser zur Gesundheits- und Leistungsvorhersage ausreicht oder welche zusätzlichen Merkmale für die Verwendung in einem Prognose-Modell von Bedeutung sein könnten. Als leistungs- bzw. gesundheitsrelevante Ereignisse (Events) wurden Brunst, Diarrhoe, Endometritis, Fieber, Infektionen, Klauenerkrankungen, Mastitis, Stress, Stoffwechselstörungen sowie Verletzungen zugeordnet. Die Bewertung der Nützlichkeit einzelner Merkmale für die Prädiktion erfolgte anhand der Erkennungsraten. Zwei- und dreistufige Entscheidungsbäume wurden entwickelt, um diese Events zu identifizieren. Ein einzelnes Merkmal ist oft nicht ausreichend, weshalb verschiedene Kombinationen von Variablen analysiert wurden. Die wichtigste Erkenntnis der vorliegenden Arbeit besteht darin, dass der Abfall der Laktosekonzentration und Laktosemenge immer ein kritisches Ereignis darstellt. Das Hauptziel eines Gesundheitsmonitorings im Milchkuhbestand sollte deshalb darin bestehen, frühzeitig eine Stoffwechselüberlastung "sichtbar" oder "erkennbar" zu machen. Unabhängig davon, welche Erkrankung sich anbahnt, muss das Herdenmanagement darauf hinwirken, die Glukoseversorgungssituation des Einzeltieres zu verbessern. Aus der Analyse für die einzelnen Herden und Laktationen kann grundlegend abgeleitet werden, dass die Ergebnisse der Milchkontrolldaten, die im Zuge der datengestützten Herdenüberwachung erhoben wurden, sich verwenden lassen, um den Leistungs- und Gesundheitsstatus der Kühe im Laktationsverlauf einzuschätzen und zu prognostizieren. Die Verwendung von Informationen zum Laktosegehalt des Gemelks verbesserten in jedem Fall die Erkennungsraten. / The aim of the current studies was to investigate whether the milk ingredient lactose can be used as a practical support management. The primary data comes from three Israeli high-performance herds, collected over several lactations. In the data preparation, the parameter "lactose content" was examined to see whether it is sufficient for a health and performance prediction or whether additional features may be of importance for usage in a forecasting model. Oestrus, diarrhea, endometritis, fever, infections, hoof diseases, mastitis, stress, metabolic disorders, and injuries have been assigned to the performance- and/or health-affecting events. The usefulness of individual features for the prediction was evaluated on the basis of the recognition rates. Thus two- and three-level decision trees have been developed to identify these events. As one single feature is often insufficient, different combinations of variables were analyzed. The most important finding of this study is that the drop in the lactose concentration and lactose quantity always represents a critical event. The main objective of a health monitoring in the dairy herd should therefore be to make a metabolic overload "visible" or "recognisable" at an early stage. Whichever disease begins to take shape, the herd management must work on improving the glucose supply situation of the individual animal. In conclusion from the analysis of the individual herds and lactations it can be inferred that the results of the milk control data collected in the course of the data-based herd monitoring can be used in order to assess and to predict the performance and health status of the cows in the course of lactation. The use of information on the lactose content of the milk improved in any case the recognition rates.