Pearlitol SD 200 based proliposomes Ketoprofen proliposome formulations using pearlitol SD 200 and different ratios of HSPC and cholesterol were prepared. HSPC (a high phase transition temperature lipid) and cholesterol (for structural rigidity) were selected because of their lower risk of oxidation and improved stability of liposomes respectively. However any variation in the composition of HSPC and cholesterol results in the deformation of vesicle, which leads to drug leakage and fusion of vesicle
lattice. The second step is also endothermic. The solvent molecules must absorb energy in order for the intermolecular forces between solvent molecules to be broken. Thus, allowing the third step to occur, which is called solvation, or heat of hydration when water is the solvent. Solvation is
metoprolol . Drug for BCS Class II has high permeability and low solubility properties . For examples , ketoprofen , bicalutamide , naproxen , phenytoin , carbamazepine and aceclofenac . Solvation rate of the drugs in BCS Class II are limited by their bioavailability . Besides that , a correlation between the in vitro solvation and in vivo bioavailability can be established in this class . They are controlled released drugs and involved in oral or IV route for administration
The world as we know it would not be the same without water. If every lake, river, and ocean were emptied and filled with something other than water, life itself would not exist. This is due to water’s unique molecular structure and arrangement due to its bonds. Water is a molecule made up of two hydrogen atoms and one oxygen atom: H2O. The hydrogen atoms have a partial positive charge and the oxygen atom has a partial negative charge. In water’s molecular structure, there are two unshared pairs
centrifugation from 100 to 300 g-force, 10 min (Harwalkar and Kalab 1981). But this method only represents the ability of curds to hold serum with extra force as many other studies called water-holding capacity or serum-holding capacity (degree of solvation). In cutting method, curds are directly cut (Calvo and Balcones 2000) in many ways which is hard to maintain identical in repeated trials. On the other hand mesh container drainage method is done by putting a curd in mesh container with another vessel
Hygroscopicity in Pharmaceutics During formulation of new and existent drugs in pharmaceutics, hygroscopicity is one of the important physical parameters that are studied so as to enhance the efficacy, stability and handling of the drug. Hygroscopicity has always been an important aspect in pharmaceutics as the bulk of the drugs either in tablet or solution form is normally hygroscopic. Up to now, there remains no universally recognized definition of hygroscopicity because it is driven by both thermodynamic
The Effect of Temperature Change During the Dilution of a Strong Acid Introduction According to the Brønsted-Lowry acid-base theory, an acid is a reactant that loses a hydrogen ion to another reactant. A strong acid is when virtually all the molecules of the acid ionises in water. In this experiment, the strong acid used was hydrochloric acid. This acid is formed when gaseous hydrogen chloride reacts with water according to the equation: When in solution, the hydronium and chloride ions formed
2.1 Introduction to Ionic Liquids Ionic liquids (ILs) are liquids composed entirely of ions. Molten salt is the term normally reserved for those systems that are liquid at high temperatures, for example NaCl (table salt is a liquid at ≈ 800 0C). Room-temperature ILs are liquid below 100˚C, have received considerable attention as substitutes for volatile organic solvents. Due to their remarkable properties, such as negligible vapour pressure, large liquidous range, high thermal stability, good ionic
patient’s system. This is especially useful when there are a set number of starting products, and one wishes to proceed down a chemical pathway in a certain number of steps. This reaction is also utilized as an “environmentally benign approach [to] solvation” (Morrison, et al., 2001) as well as in the production of “complex natural products” in chemical synthesis (Akiyama, et al., 2009). Robinson Annulation is a useful reaction, but not the simplest, so other types of enantioselective synthesis reactions
Oxides of Hydrogen Introduction: Hydrogen atoms can react with oxygen atoms forming different compounds. There are mainly two types, one is water and the other is hydrogen peroxide. Structure: A water molecule is made up of two hydrogen atoms and one oxygen atom joining together by covalent bonds. The shape of it is bent and its bond angle is of 105°. The structure is shown below. [IMAGE] A hydrogen peroxide molecule consists of two hydrogen atoms and two oxygen atoms joined
Molecular docking is a key tool in structural molecular biology and computer-assisted drug design. The goal of ligand—protein docking is to predict the predominant binding mode(s) of a ligand with a protein of known three-dimensional structure. Successful docking methods search high-dimensional spaces effectively and use a scoring function that correctly ranks candidate dockings. Garrett M. Morris and Marguerita Lim-Wilby, Molecular Docking, In Molecular Modeling of Proteins Methods in Molecular
affecting the isomeric ratio. The improvement was more significant with aromatic and long-chain aldehydes that induced large hydrophobic effects. Consequently, water’s ability in stabilising the polar transition state and in reducing the energy of solvation through hydrophobic associations were suggested to cause the improved reaction rates and selective yields.10 In the aqueous Wittig reaction, a combination of other factors could further improve the reaction. These included the increase of temperature
The treatment of surface wastewater is aimed at bringing contaminated water back to its previous state for domestic use or otherwise. Some of the sources of wastewater include industrial effluents from manufactures, agricultural effluents, agro-industrial as well as domestic wastewater from sinks, bathtubs, toilets, and so on. Particles in the water from the various sources include bacteria, organic matters, and sand which cause the water to be turbid or discoloured in appearance and have an unpleasant
are a cleansing agent, an antiseptic, occasionally as a preservative and used as a flux for silver soldering. The purpose of the experiment was to determine the thermodynamic quantities, enthalpy (ΔH°) and the standardized entropy (ΔS°) of the solvation of sodium tetraborate decahydrate, borax, in water. This was achieved by observing the effect various temperatures have on the solubility product of borax. Experimental Details The experiment required that a 250 mL beaker be filled with 75-85
a positive effect on dentin bonding. [21] Stape et al also found that dentin pre-treatment with low dimethyl sulfoxide concentrations improves long-term bonding at the expense of an extra step in the etch-and-rinse bonding technique. Therefore, solvation of adhesive monomers by dimethyl sulfoxide could possibly benefit dentin bonding in a similar manner, but without the need of an extra bonding step, as long as the resin mechanical/physical properties would not be compromised.
Bioinorganic Coordination Chemistry This experiment uses H2TTP made during the last lab and hydrated copper (II) acetate to convert the H2TTP to Cu(TTP). The reaction proceeds by being refluxed for 30 minutes. The final product is a non-iridescent purple color, unlike the vivid, shimmering purple color of the starting H2TTP. Introduction Thin layer chromatography, or TLC, is used as a prerequisite for column chromatography. When performing types of chromatography, like TLC, the polarity
I turned on my laptop one hot September, and as I decided to re-watch Snowpiercer, then a thought occurred to me about what happens when a huge disaster comes to drain most of humanity population to short numbers. Sadly, Snowpiercer takes my thought into a reality that I can 't stop from keeping my eyes from being glued to my screen. Knowing very well what the movie has in store for the viewer and, yet I knew I was going for another roller coaster ride that would make me question humanity since of
Introduction An informal definition of Henry’s Law states that the solubility of a compound in a solvent is directly proportional to the partial pressure of the compound in the vapour phase, at low partial pressures. In a plot of concentration dissolved vs. partial pressure, the slope of the curve is the Henry’s Law Constant (HLC). The system is taken to be at equilibrium; that is the Gibbs free energy is at a global minimum so the macroscopic properties of the system are static. Unfortunately this
Energy In this lab, we dissolved Sodium hydroxide, a strong base and corrosive, in 50ml of water to observe the change in temperature of the solution. At room temperature, sodium hydroxide is a white crystal-like odorless solid that absorbs moisture from the air. When dissolved in water or used to neutralized acid, it unleashes substantial heat which undoubtedly the predominant catalyst for the change in the energy. The heat that is produced by sodium hydroxide is sufficient to ignite combustible
What is Electrolysis? Electrolysis is a chemical change brought about by the passing of an electric current through a solution or melt. It is also used to produce alkalis and elements such as chlorine and hydrogen. The process involves the addition (oxidation) or subtraction (reduction) of ions in elements. The electric current motions the ions to proceed onto the electrodes. For example, the cations (positive ions) move to the negative electrode (cathode) and the positive electrode (anode) will