AbstractObjective: Orally disintegrating tablets (ODTs) recently have gained much attention to fulfill the needs for pediatric, geriatric, and psychiatric patients with dysphagia. Aim of this study was to develop new ODT formulations containing mirtazapine, an antidepressant drug molecule having bitter taste, by using simple and inexpensive preparation methods such as coacervation, direct compression and to compare their characteristics with those of reference product (Remereon SolTab).Materials and methods: Coacervation method was chosen for taste masking of mirtazapine. In vitro characterization studies such as diameter and thickness, weight variation, tablet hardness, tablet friability and disintegration time were performed on tablet formulations. Wetting time and in vitro dissolution tests of developed ODTs also studied using 900?mL 0.1?N HCl medium, 900?mL pH 6.8 phosphate buffer or 900?mL pH 4.5 acetate buffer at 37?±?0.2?°C as dissolution medium.Results: Ratio of Eudragit® E-100 was chosen as 6% (w/w) since the dissolution profile of A1 (6% Eudragit® E-100) was found closer to the reference product than A2 (4% Eudragit® E-100) and A3 (8% Eudragit® E-100). Group D, E and F formulations were presented better results in terms of disintegration time. Dissolution results indicated that Group E and F formulations showed optimum properties in all three dissolution media.Discussion: Formulations D1, D4, D5, E3, E4, F1 and F5 found suitable as ODT formulations due to their favorable disintegration times and dissolution profiles.Conclusion: Developed mirtazapine ODTs were found promising in terms of showing the similar characteristics to the original formulation. 相似文献
Objectives: The aim of this in vitro study was to evaluate the effect of different desensitizers’ application on the microleakage of previously restored Class V composite resin restorations.
Materials and methods: Class V cavities were prepared on the buccal surfaces of 40 extracted human third molars. Forty box-shaped cavities were divided into four groups, based on the desensitizers used (n = 10). All teeth were restored with the same bonding agent and composite material. No desensitizer was applied in the control group. In the experimental groups, BisBlock, Gluma and Universal bonding agents were the desensitizers. The desensitizers were applied after completion of composite restorations according to manufacturers’ instructions. All specimens were then thermocycled at 5–55 °C, with a 10-s dwell time for 500 cycles. The samples were then immersed in 0.5% methylene blue dye for 24 h, sectioned into two equal halves, evaluated for microleakage using a stereomicroscope at 30× magnification and scored on a scale of 0–3. The data were analysed using the Kruskal–Wallis test at the significance level p < 0.05.
Results: There were no significant differences in microleakage after desensitizer application (p > 0.05). However, based on the obtained numerical values in our study, while the BisBlock and bonding groups showed lower microleakage at the occlusal margin, BisBlock, Gluma and bonding group showed lower microleakage at the gingival margin compared to the control group.
Conclusions: The application of desensitizers as a post-treatment option could be considered an advisable procedure to minimize microleakage. 相似文献
Powder Metallurgy and Metal Ceramics - In this study, different heat treatment regimes, such as sintering, sintering with low-pressure cementation, and only low-pressure cementation were applied to... 相似文献
Random and <001> textured potassium sodium niobate – [K,Na]NbO3 (KNN) ceramics with 1 mole% CuO sintering aid were fabricated in ribbon form through a combination of novel alginate gelation process and templated grain growth methods using platelike sodium niobate ‐ NaNbO3 (NN) template particles. The platelike NN template particles were prepared by a two‐step molten salt synthesis method. Ribbons were drawn from alginate‐based slurries without or with 10 wt% NN template particles using 50 mm long slit nozzle with a rectangular orifice of 10 mm × 1 mm. Development of crystallographic texture as a result of varying sintering time and temperature was evaluated through the calculation of the degree of orientation as measured by the Lotgering factor (?(001)) and an ?(001) of 0.81 was achieved. The electrical properties of textured ribbons were evaluated with polarization and strain versus electric field measurements. 相似文献
The purpose of this study is to investigate the effects of Ti addition (1 and 2% Ti) and aging heat treatment on the mechanical and wear characteristics of Al-12Si-20Mg cast alloys. In preliminary studies conducted to determine the aging parameters, cast alloys were kept at 550 °C for 2 h before being quenched into water and aged at 200 °C for five different periods (3, 6, 9, 12, and 15 h). As the specimen aged for 12 h had the highest hardness value, all the specimens were aged at 200 °C for 12 h. The microstructures of the as-cast and aged specimens were analyzed using an optical microscope and a scanning electron microscope. The hardness of the investigated alloys was measured by micro-hardness test. The wear tests were carried out using the pin-on-disk model wear test apparatus, and the results were evaluated according to weight loss. According to the wear test results, the wear behavior of the investigated alloys changed depending on the aging heat treatment applied and the load. While Ti addition and the aging heat treatment applied reduce the weight loss at low loads (5 N), they increase the weight loss at higher loads (10 and 20 N). 相似文献
A significant proportion of the cost of winning minerals or aggregates in an open cast mine is related to the mass haul. The quality of the haul roads is an important factor in the efficiency and length of turn-round time. The paper reports a study into the use of plate loadings tests as a quick and easy means of establishing a preliminary bearing capacity. Various relationships have been obtained between bearing capacity and the results of field and laboratory tests. Good performance indices (r, RMSE, VAF) indicate they can be used for an initial assessment of the bearing capacity of rock units ranging from weak to strong. In addition, classes for bearing capacity of rock units have been suggested based on field observations and measurements. 相似文献
Low density lipoprotein (LDL) cholesterol is a major ingredient of the plaque that collects in the coronary arteries and causes coronary heart diseases. Among the methods used for the extracorporeal elimination of LDL from intravasal volume, immunoaffinity technique using anti-LDL antibody as a ligand offers superior selectivity and specificity. Proper orientation of the immobilized antibody is the main issue in immunoaffinity techniques. In this study, anti-human β-lipoprotein antibody (anti-LDL antibody) molecules were immobilized and oriented through protein A onto poly(2-hydroxyethyl methacrylate) (PHEMA) cryogel in order to remove LDL from hypercholesterolemic human plasma. PHEMA cryogel was prepared by free radical polymerization initiated with N,N,N′,N′-tetramethylene diamine (TEMED). PHEMA cryogel with a swelling degree of 8.89 g H2O/g and 67% macro-porosity was characterized by swelling studies, scanning electron microscope (SEM) and blood compatibility tests. All the clotting times were increased when compared with control plasma. The maximum immobilized anti-LDL antibody amount was 63.2 mg/g in the case of random antibody immobilization and 19.6 mg/g in the case of oriented antibody immobilization (protein A loading was 57.0 mg/g). Random and oriented anti-LDL antibody immobilized PHEMA cryogels adsorbed 111 and 129 mg LDL/g cryogel from hypercholesterolemic human plasma, respectively. Up to 80% of the adsorbed LDL was desorbed. The adsorption–desorption cycle was repeated 6 times using the same cryogel. There was no significant loss of LDL adsorption capacity. 相似文献