As coprocessed excipients (CPE) gain a lot of focus recently, this article compares three commercially available CPE of Avicel brand, namely, CE 15, DG, and HFE 102. Comparison is based on measured physical properties of coprocessed mixtures, respectively, flow properties, pycnometric density, mean particle size, specific surface area, moisture content, hygroscopicity, solubility, pH leaching, electrostatic charge, SEM images, and DSC. Tablets were made employing three pressure sets. Viscoelastic properties and ejection force were assessed during compression, as well as pycnometric density, mass uniformity, height, tensile strength, friability, disintegration, and wetting times. Avicel CE 15 is of mid-range flow properties, contains mid-size and nonspherical particles, and has high hygroscopicity, growing negative charge, best lubricity, lowest tensile strength, and mid-long disintegration times. Avicel DG possesses the worst flow properties, small asymmetrical particles, lowest hygroscopicity, stable charge, intermediate lubricity, and tensile strength and exhibits fast disintegration of tablets. Finally, Avicel HFE 102 has the best flow properties, large symmetrical particles, and middle hygroscopicity and its charge fluctuates throughout blending. It also exhibits inferior lubricity, the highest tensile strength, and slow disintegration of tablets. Generally, it is impossible to select the best CPE, as their different properties fit versatile needs of countless manufacturers and final products.

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Macrophages possess an innate ability to scavenge heterogenous objects from the systemic circulation and to regulate inflammatory diseases in various organs via cytokine production. That makes them attractive targets for nanomedicine-based therapeutic approaches to inflammatory diseases. In the present study, we have prepared several different poly(lactic-co-glycolic acid) (PLGA) polymer nanospheres for macrophage-targeted drug delivery using both nanoprecipitation and emulsification solvent evaporation methods. Two experimental linear PLGA polymers with relatively low molar weight, one experimental branched PLGA with unique star-like molecular architecture, and a commercially available PLGA, were used for nanosphere formulation and compared to their macrophage uptake capacity. The nanosphere formulations labelled with loaded fluorescent dye Rhodamine B were further tested in mouse bone marrow-derived macrophages and in hepatocyte cell lines AML-12, HepG2. We found that nanospheres larger than 100 nm prepared using nanoprecipitation significantly enhanced distribution of fluorescent dye selectively into macrophages. No effects of nanospheres on cellular viability were observed. Additionally, no significant proinflammatory effect after macrophage exposure to nanospheres was detected as assessed by a determination of proinflammatory cytokines Il-1β and Tnfα mRNA. All experimental PLGA nanoformulations surpassed the nanospheres obtained with the commercially available polymer taken as a control in their capacity as macrophage-specific carriers.

Modified starches are widely employed excipients in tablets compression. The ability of materials to deform under pressure (compressibility) and create strong compacts (compactability) is then important for tablet manufacture. This study aims to evaluate and compare two partially pregelatinized starches, namely, Starch 1500 and Lycatab C, from the perspectives of compressibility, compactability, and lubricant sensitivity. Compressibility is evaluated by means of the compression energy profile and a stress relaxation test. Compactability is evaluated by means of the tablets tensile strength, and lubricant sensitivity is characterized by the lubricant sensitivity ratio (LSR) values. The lubricants employed are magnesium stearate and sodium stearyl fumarate at concentrations of 0.5% and 1%, respectively. In the case of the mixtures with 1% magnesium stearate, the influence of the mixing time is also evaluated. Starch 1500 shows better compressibility than Lycatab C due to its lower precompression and total energy values. On the opposite, the plasticity is higher for Lycatab C. This material has also better compactability, yields stronger tablets, but has higher lubricant sensitivity than Starch 1500. Different compressibility and compactability are found for Lycatab C and Starch 1500 and therefore, they cannot be easily interchanged in tablet manufacture.

The utilization of co-processed excipients (CPEs) represents a novel approach to the preparation of orally disintegrating tablets by direct compression. Flow, consolidation, and compression properties of four lactose-based CPEs—Cellactose® 80, CombiLac®, MicroceLac® 100, and StarLac®—were investigated using different methods, including granulometry, powder rheometry, and tablet compaction under three pressures. Due to the similar composition and the same preparation technique (spray drying), the properties of CPEs and their compacts were generally comparable. The most pronounced differences were observed in flowability, undissolved fraction after 3 min and 24 h, energy of plastic deformation (E2), ejection force, consolidation behavior, and compact friability. Cellactose® 80 exhibited the most pronounced consolidation behavior, the lowest values of ejection force, and high friability of compacts. CombiLac® showed excellent flow properties but insufficient friability, except for compacts prepared at the highest compression pressure (182 MPa). MicroceLac® 100 displayed the poorest flow properties, lower ejection forces, and the best mechanical resistance of compacts. StarLac® showed excellent flow properties, the lowest amounts of undissolved fraction, the highest ejection force values, and the worst compact mechanical resistance. The obtained results revealed that higher compression pressures need to be used or further excipients have to be added to all tested materials in order to improve the friability and tensile strength of formed tablets, except for MicroceLac® 100.

This paper deals with a study of the novel coprocessed dry binder Combilac®, which contains 70% of α-lactose monohydrate, 20% of microcrystalline cellulose and 10% of native corn starch. These tests include flow properties, compressibility, lubricant sensitivity, tensile strength and disintegration time of tablets. Compressibility is evaluated by means of the energy profile of compression process, test of stress relaxation and tablet strength. The above-mentioned parameters are also evaluated in the physical mixture of α-lactose monohydrate, microcrystalline cellulose and native corn starch and compared with Combilac. Combilac shows much better flowability than the physical mixture of the used dry binders. Its compressibility is better, tablets possess a higher tensile strength. Neither Combilac, nor the physical mixture can be compressed without lubricants due to high friction and sticking to the matrix. Combilac has a higher lubricant sensitivity than the physical mixture of the dry binders. Disintegration time of Combilac tablets is comparable with the disintegration time of tablets made from the physical mixture.

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