Different Types Of Diluents Research Articles

FORMULATION OF ORALLY DISINTEGRATING TABLETS OF CINNARIZINE BY USING DIRECT COMPRESSION METHOD

Objective: The aim of this work was to formulate and evaluate orally disintegrating tablets of cinnarizine that were prepared by direct compression method using different types of diluents and super disintegrants. The rationale behind this work was to accelerate the disintegration of the tablet to provide rapid dissolution, quick action and enhanced bioavailability of the drug.Methods: The tablets were prepared by direct compression method using different types of diluents as mannitol, microcrystalline cellulose (MCC), and lactose. Different super disintegrants were used such as crospovidone (CP), sodium starch glycolate (SSG) and Kyron T-314; Kyron T-314 was used in different concentrations of 5%, 6%, 7%, and 8%. The prepared formulae (F1-F9c) were subjected to flowability studies and post-compression evaluation studies. The optimized formula was selected depending on the time of disintegration and dissolution; then it was subjected to drug-excipient compatibility study and stability study.Results: Flowability results were ranging from excellent, excellent to good, and good to fair according to the type of the diluent used. All of the prepared tablets showed acceptable hardness, friability, drug content, and disintegration. A rapid disintegration of 11.66±2.25 s with the highest percentage 2 min-drug release of 74.55±3.01% was obtained by using the diluent lactose and the super disintegrant Kyron T-314 (8%) in the formula F9c. The infrared spectroscopic studies of the formula F9c showed no drug-excipient interaction. In addition, the stability study indicated that the optimized formula is a stable formula.Conclusion: Formula F9c of a rapidly disintegrating tablet was easy to be manufactured, and the results showed that this formula had a rapid disintegration, high dissolution profile, no noticeable chemical incompatibility and it was stable upon storage.

Effect of the diluent on the solvent extraction of neodymium(III) by bis(2-ethylhexyl)phosphoric acid (D2EHPA)

The effect of different types of diluents on the extraction of neodymium(III) from a chloride aqueous feed solution by the acidic extractant bis(2-ethylhexylphosphoric) acid (D2EHPA) was investigated. A total of 11 aliphatic, mixed aliphatic-aromatic and aromatic diluents were considered. D2EHPA was very well miscible with all diluents, even at 90% (v/v) of extractant. Aliphatic diluents gave the highest extraction efficiencies, while aromatic diluents did suppress the formation of emulsions or gels. Although a good separation of Dy(III) over Nd(III) was observed at 0.5 mol/L D2EHPA in all diluents, aromatic diluents were found to yield the highest separation factors. This study shows that the effect of the diluent on the extraction behaviour of Nd(III) is primarily determined by the aliphatic/aromatic content of the diluent. Diluents with the same concentration of aromatics show very similar behaviour. The choice of a diluent can be based on factors other than the extraction behaviour, for instance price and volatility.

The stability of ceftriaxone sodium in vials using different diluents

Ceftriaxone sodium is an important antibiotic used for intravenous or intramuscular administration. The aim of this study was to evaluate the stability of ceftriaxone sodium in vials that dissolved in different types of diluents when stored in different degrees of temperature and different concentrations. Six diluents were used, lidocaine 1%, lidocaine 2%, dextrose 5%, Nacl 0.9%, mixture serum, sterile water used for injection. The solutions of ceftriaxone sodium in sterile water and dextrose 5% (100mg/ml)showed the most stability for 3 days when stored at 25°C, and for 10 dayswhen stored at 4°C, whereas solutions in lidocaine 2% showed the lowest stability for 8 hours at 25°C, and 8days at 4°C. The concentration of the resulted solution has an important effect on the stability such as, the stability of ceftriaxone sodium in lidocaine 1%with concentration (100mg/ml) showed stability for 9 days when stored at 4°C, whereas for 3 days with concentration (250mg/ml).

Improving the Quality of Porous Silica Ceramics by the Method of Plasticization of Slurries for their Application in Thermal Protection Structures

Objectives: The problem of producing a cellular ceramic from well-foamed slurries with low water content can be solved by introducing diluting additives - salts of sodium, potassium, lithium and organic plasticizers. Methods/Statistical Analysis: Suttard's viscometer was used to study the theology of silica slurries. The experimental data were processed by methods of mathematical statistics, using Student-Fisher criterion. It was established, that there are two different areas of concentration of diluents: effective (reducing the viscosity of suspension) and inefficient (increasing the viscosity of suspension). Findings: The experiments show, that in the case of concentrated siliceous suspensions siliceous inorganic diluents show the maximum water-reducing effect. This refers to salts based on lithium and sodium compounds (Na 4 P 2 O 7 , NaOH, Na 2 SiO 3 , Li 2 CO 3 , Na 2 CO 3 ), with their content not exceeding 0,5...0,75 %. The effect of the concentration of electrolytes on the viscosity index is described by complex processes associated with specific adsorption of ions (electrolytes are determined by the more complicated processes associated with the specific adsorption of ions). The purpose of this work is to determine the applications of the effective concentration of different types of diluents. Application/Improvements: Experiments and numerical calculations show that diluting effectiveness of the admixes in the suspensions of the gaize was achieved: for water-reducing effect 1.25…1.29; for reduction of water demand 20…22.6 %.

Reactive extraction of sodium hydroxide from alkali solutions for the separation of sodium and aluminum—Part II. Effect of diluent

Enhancing the precipitation of Al(OH)3 from supersaturated sodium aluminate solution has been a challenge for the alumina industry for decades in its effort to increase the productivity. However, limited by the thermodynamic equilibrium of alumina solubility in caustic solutions, the processes that are available to date for promoting the precipitation of Al(OH)3 are unsatisfactory. An acid–base reactive solvent extraction method is proposed to enhance the separation of sodium hydroxide from sodium aluminate mother liquor by creating a condition for re-precipitation. The extraction process has been reported in Part I of this study by the present authors. In this paper the effects of diluents on sodium extraction when using 2-tert-butyl-4-methylphenol as the main organic extractant were systematically investigated. According to the classification of diluents, the capabilities for extracting sodium in different types of diluents were compared, and the protonic polar diluents were identified as being the most effective diluent. In the absence of alkyl phenol organic extractant, the sodium extraction equilibrium in 1-octanol and 2-ethyl hexanol, and the co-extraction of water in each of them were compared. In the presence of alkyl phenol, the extraction capabilities for sodium in different C8 alcohols, including 1-octanol, 2-ethyl hexanol and 2-octanol, were compared and analyzed. The results showed that 1-octanol is the most effective diluent among the three that are studied in this project. Furthermore, inert diluents including kerosene, octane and heptane, were used to dilute the pure 1-octanol solvent in different proportions in order to decrease the viscosity of the organic phase. The effects of the inert diluent on sodium extraction and water co-extraction were studied. Finally, the particle size distributions in the equilibrated organic phases and the Margules ternary 2-suffix equations were introduced to discuss the mechanisms of sodium extraction by 1-octanol and 2-ethyl hexanol. The results of this systematic research are expected to provide valuable guidance for the selection of diluents.

Varying the porous structure of polystyrene/divinylbenzene beads prepared by Ugelstads activated swelling technique and examining its reversed phase HPLC properties

Monodisperse unfunctionalized polystyrene/divinylbenzene beads were prepared via Ugelstads two-step activated swelling procedure. The modification of the porous structure was achieved in two different ways, by either changing the kind and amount of diluent or the concentration of crosslinker. Overall 10 different types of diluents, both solvent and nonsolvent types, were utilized. In all cases divinylbenzene was used as crosslinking agent in concentrations of 55% and 80%, which are commercially available, and 100%, which had to be synthesized. The size and morphology of these particles were examined with scanning electron microscopy. For the analysis of the internal porous structure inverse size exclusion chromatography was conducted. Depending on the monomer and diluent composition beads in the range of 3.4–4.5μm having a specific surface area from 90 to 1898m2/g were synthesized. Separation performance was then also investigated using RP-HPLC with benzene and propylbenzene as analytes. Porous and reversed-phase properties were subsequently linked to explain the observed shift in retention and efficiency. Polymers having the highest specific surface area and the smallest mean pore diameter exhibited the best performance with reduced plate height of 3.1.

Development and evaluation of nifedipine controlled release tablets prepared using mucoadhesive swellable polymer

Nifedipine is embedded in Gelcarin GP-379 to develop a prolonged release matrix. The effect of polymers levels (15, 20, 30 and 50% w/w), diluent type (lactose Fast Flo, DiTab, and Avicel PH-101), and drug levels (13, 20 and 30% w/w) on in vitro release rate of the drug were investigated. The formulation containing 13% nifedipine, 20% Gelcarin GP-379, and lactose Fast Flo controlled the dissolution rate of nifedipine and released approximately 51% drug at 8 h of testing dissolution. The use of different types of diluents, different drug levels, and different rotational speeds during dissolution testing did affect the drug release rate from the swellable matrices. The dissolution data were analyzed according to Higuchi model, zero order, first order, and Peppas kinetic model. Drug release was found to follow the anomalous diffusion model for swellable matrix.

Determination of Mercury in Whole Blood and Urine by Inductively Coupled Plasma Mass Spectrometry

The conventional method for the determination of mercury in clinical samples is cold vapor atomic absorption spectrometry. Sample digestion or pretreatment require large sample volume and long sample preparation time. The inductively coupled plasma mass spectrometry (ICP-MS) method developed in this study requires only 100 microL of sample with practically no preparation, except for dilution with diluent. Significant savings in sample volumes, reagents, technician time, and analysis time are realized. Among different types of diluents, the one containing acid, tert-butanol, and potassium dichromate gave the best results to remove the mercury memory effect. The interassay precisions for whole blood and urine were < 5% and < 8%, respectively, and the intra-assay precisions were < 3% and < 7%, respectively. The lower limits of detection were 0.13, 0.17, and 0.26 microg/L for aqueous standard, urine, and whole blood, respectively. The developed ICP-MS method correlated well with the atomic absorption method and can offer an alternative to the atomic absorption method for mercury analysis with less sample volume requirement as well as shorter analysis time.

Evaluation of the Overall Accuracy of the DeLaval Cell Counter for Somatic Cell Counts in Ovine Milk

The DeLaval cell counter (DCC) is a portable device designed for on-farm somatic cell count (SCC) analysis in bovine milk. This study evaluated the performance of the DCC when analyzing ovine milk. A total of 29 composite ovine milk samples, ranging between 20×103 and 2,200×103cells/mL, were divided into 15 aliquots/milk sample corresponding to 5 SCC methods using 3 types of preservation (unpreserved, azidiol, and bronopol). The SCC methods were the Fossomatic (FSCC), the DCC in undiluted samples, and the DCC in samples diluted 1:1 in 3 different types of diluents (PBS + Triton X-100, PBS + ethidium bromide + Triton X-100, and PBS + propidium iodide + Triton X-100). All analyses were carried out in duplicate. In addition, each sample was analyzed in quadruplicate by the direct microscopic method (DMSCC) using Pyronin Y-methyl green as a stain. Comparison of methods was based on overall accuracy studies (means comparison, repeatability, and regression studies vs. DMSCC and FSCC as reference methods). The DCC methods used to analyze milk samples diluted in staining solution (with ethidium bromide or propidium iodide) showed large coefficients of regression (b = 0.91 to 1.01) and correlation (r>0.99) when compared with the DMSCC and FSCC methods. In these samples the DCC gave repeatability values (sr = 33 to 48×103cells/mL) similar to the DMSCC (sr = 36×103cells/mL), and their log SCC means (5.52 to 5.54) did not differ from the reference value (5.54). However, undiluted samples analyzed by the DCC method showed large standard deviations of repeatability and SCC values lower than those by the DMSCC or FSCC methods, probably because of the high solids content in ovine milk. The type of preservation did not affect the outcomes. Consequently, the DCC was determined to be accurate when analyzing diluted ovine milk based on comparison with the SCC reference methods.

Metal replacement compounds

Enhancing the precipitation of Al(OH)3 from supersaturated sodium aluminate solution has been a challenge for the alumina industry for decades in its effort to increase the productivity. However, limited by the thermodynamic equilibrium of alumina solubility in caustic solutions, the processes that are available to date for promoting the precipitation of Al(OH)3 are unsatisfactory. An acid–base reactive solvent extraction method is proposed to enhance the separation of sodium hydroxide from sodium aluminate mother liquor by creating a condition for re-precipitation. The extraction process has been reported in Part I of this study by the present authors. In this paper the effects of diluents on sodium extraction when using 2-tert-butyl-4-methylphenol as the main organic extractant were systematically investigated. According to the classification of diluents, the capabilities for extracting sodium in different types of diluents were compared, and the protonic polar diluents were identified as being the most effective diluent. In the absence of alkyl phenol organic extractant, the sodium extraction equilibrium in 1-octanol and 2-ethyl hexanol, and the co-extraction of water in each of them were compared. In the presence of alkyl phenol, the extraction capabilities for sodium in different C8 alcohols, including 1-octanol, 2-ethyl hexanol and 2-octanol, were compared and analyzed. The results showed that 1-octanol is the most effective diluent among the three that are studied in this project. Furthermore, inert diluents including kerosene, octane and heptane, were used to dilute the pure 1-octanol solvent in different proportions in order to decrease the viscosity of the organic phase. The effects of the inert diluent on sodium extraction and water co-extraction were studied. Finally, the particle size distributions in the equilibrated organic phases and the Margules ternary 2-suffix equations were introduced to discuss the mechanisms of sodium extraction by 1-octanol and 2-ethyl hexanol. The results of this systematic research are expected to provide valuable guidance for the selection of diluents.

Relation of lipid adsorptivity of powders to their suitability as insecticide diluents

does not appear. First page follows. Introduction It has been well established that sorptive powders can cause the death of insects, sometimes with remarkable rapidity, by removing a portion of the very thin layer of lipid, averaging about 0.25 ? in thickness, that covers the insect epicuticle and normally prevents desiccation (Alexander et al., 1944);4(Hurst, 1948); (Helvey, 1952); (Glynne Jones, 1955); (Nair, 1957); (Ebeling and Wagner, 1959); (Wagner and Ebeling, 1959); (Tarshis, 1959), (1960), (1961); and (Micks, 1960). It thus might be assumed that sorptive diluents should increase the insecticidal effectiveness of toxicants by adding their independent effect as lipid removers. However, preliminary tests showed that this is not always the case; with some toxicants, the sorptiveness of the diluent proved to be highly detrimental. Obviously, if an inert powder having the ability to cause the death of an insect is to be less effective as a diluent than one without insecticidal effect, some adverse action must take place when that powder is combined with the toxicant. The purposes of the present investigation were (1) to determine the independent influence of sorptive and nonsorptive powders on the ultimate effects of the toxicants by applying them to insects for brief periods before the latter were treated with the toxicants; (2) to determine the effects of these same powders when used as diluents for the toxicants; and (3) to find an explanation for the differences in insecticidal effectiveness of toxic dusts that might be caused by the different types of diluents. Materials and Methods The insect species used in this investigation were adult Drosophila pseudoobscura; adult males of the German cockroach, Blattella germanica, and of the brown-banded cockroach, Supella supellectilium; full-grown nymphs of the drywood termite, Kalotermes minor, and of the dampwood termite, Zootermopsis angusticollis. Drosophila pseudoobscura is much larger than the familiar D. melanogaster and much more resistant both to the effects of toxicants and to the desiccating effect of sorptive powders. The flies used in the present investigation were obtained from the laboratory of Dr. Carl C. Epling, who rears them in large numbers throughout the year in connection with genetics investigations. The flies are reared in a uniform manner in half-pint milk bottles, and