Analytical chemistry may be defined as the study of separation, identification, and the quantification of the chemical components of natural and artificial materials1 constituted of one or more substances. Analytical chemistry is divided in to two main types, qualitative analysis that is to say the identification of the chemical species present the sample, and quantitative analysis determines the amount of certain element or compound in the substance i.e., sample. Pharmaceutical analysis1-3 plays a vital role today and can be considered as an interdisciplinary subject. Pharmaceutical analysis derives its principles from different branches of science like Chemistry, Microbiology, Nuclear Science and Physics, etc. Analytical method is a definite application of a technique to work out an analytical problem. Analytical instrumentation plays a prominent role in the production and evaluation of novel products and in the protection of consumers and the environment. This instrumentation provides the lower detection limits required to assure safe foods, drugs, air and water.
1.02 Typical instrumental techniques:
The methods of estimation of drugs are separated into physical, chemical, physicochemical and biological ones. Of these methods, generally physical and physicochemical methods are used the most. Physical methods of analysis involve the studying of the different physical properties of a substance. They are determination of the solubility, transparency or degree of turbidity, color, density or specific gravity (for liquids), melting, freezing, boiling points and moisture content. Physicochemical methods4,5 are used to study the physical phenomena that occur as a result of chemical reactions. In the Physicochemical methods Optical (...
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... suitable for the later analysis. In some instances, the binding of the active ingredients to polar excipients such as lactose and starch reduces the effectiveness of extraction. This becomes significant particularly when the dose of drug is very tiny. Generally used method for reducing the adsorption losses and increasing the selectivity of the extraction is two-phase extraction. Here one of the solvents is always water. This solvent dissolves lactose, which is generally the main component of the excipients thereby affording favorable conditions for extraction of the drug by the other solvent, which is immiscible with water. Starch, which is also vital from the point of view of adsorption losses, can be dissolved by treatment with diastase. The organic solvent is typically chloroform but ethyl acetate, diethyl ether, iso-octane and a few others have also been used.
There is a technique called polarimetry that uses polarized light and asymmetric carbons like those found in glucose. The amount of polaritization can be used to determine the amount of active molecules present in solution.3 The equation used is measured rotation of angle = (a)lc, (a) is optical activity, c is the concentration, and l is the pathlenght. The concept seems similar to Beers
Craig, D. Q. (2002). Pharmaceutical Applications of Micro-Thermal Analysis. Journal of Pharmaceutical Science, 91(5), 1201-1213.
The objective of this experiment was to perform extraction. This is a separation and purification technique, based on different solubility of compounds in immiscible solvent mixtures. Extraction is conducted by shaking the solution with the solvent, until two layers are formed. One layer can then be separated from the other. If the separation does not happen in one try, multiple attempts may be needed.
Chromatography is a method to distinguish between organic and inorganic compounds so that they can be analyzed and examined. By performing analysis of a compound, a scientist can figure out what makes up the compound. Chromatography related techniques have been used for centuries to separate materials such as colorants extracted from plants. However, Chromatography was first developed in 1900 by Russian scientist Michael Tswett. He continued
Discuss the possible drug and excipient-related constrains of the formulation (no identity of the drug was given to you at this
The purpose of this experiment was to learn and preform an acid-base extraction technique to separate organic compounds successfully and obtaining amounts of each component in the mixture. In this experiment, the separation will be done by separatory funnel preforming on two liquids that are immiscible from two layers when added together. The individual components of Phensuprin (Acetylsalicylic acid, Acetanilide, and Sucrose as a filler) was separated based upon their solubility and reactivity, and the amount of each component in the mixture was obtained. Also, the purity of each component will be determined by the melting point of the component.
Once the mixture had been completely dissolved, the solution was transferred to a separatory funnel. The solution was then extracted twice using 5.0 mL of 1 M
The conical vial was placed in a small beaker and allowed to cool to room temperature. The mixture was Cooled thoroughly in an ice bath for 15-20 minutes and crystals collected by vacuum filtration on a Hirsch funnel. The vial was rinsed with about 5 mL of ice water and transferred into to the Hirsch funnel and again washed with two additional 5mL portions of ice water. Crystals were dried for 5-10 minutes by allowing air to be drawn through them while they remained on the Hirsch funnel. The product was transferred to a watch glass plate and allow the crystals to dry in air. Crude acetaminophen product was weighed and set aside a small sample for a melting point determination and a color comparison after the next step. Calculation of the percentage yield of crude acetaminophen (MW = 151.2). was done and recorded in the lab notebook.
In conclusion Gas Chromatography has many uses to separate and analyse compounds and to be able find separate components in a mixture to identify any unknown components. Because of it's simplicity and effectiveness it is one of the most important tools to chemistry. Like most analytical techniques it has its advantages such as not being harmful to the sample be used and disadvantages such as not being particularly use with liquids that change temperate easily.
Analysis of Aspirin Tablets Aim --- To discover the percentage of acetylsalicylic acid in a sample of aspirin tablets. ----------------------------------------------------------------- In order to do this, the amount of moles that react with the sodium hydroxide must be known. This is achieved by using the method of back titration.
The book Methods of Separating Mixtures defines chromatography as “a very widely used method of separating mixtures, particularly
The choice of mobile phase depends on the chemical nature of the compound of interest and could be purely organic, inorganic or a mixture of both in gradient. Most commonly used mobile phases are organic solvents like acetonitrile or methanol. Some HPLC analysis require the use of water free solvents as mobile phase and in such cases acids like formic acid, phosphoric acid, trifluoroacetic or salts which will assist in separation of components in the sample are used.
In chemistry, Colorimetry is used a lot. They use it for things such as colour painting, food manufacturing, and textiles. Colorimetry can also be used to measure light. The amount of light absorbed is called and also is measured as the absorbance which is a use of the coloured solute concentration. To use a colorimeter, different kinds of solutions have to be made, this includes a regulator or orientation of identified concentration.
Drug is a chemical which alters the processes in the organism, which is used in the medicine for prevention, diagnosis and treatment of the diseases (Farlex, 2011). Drug discovery is a long term process that needs money investment. The process of drug investigation takes approximately from 9 to 15 years during which the number of chemicals that can become drug is reduced from 10,000 to 1-2 (Saparov, 2011). Even after manufacturing the drug is studied by scientists for modifying its structure, delivery and effects on the organism. Drug discovery consists of several stages which help to examine its effectiveness and side effects.
Pharmacology is the science of drugs (from Greek pharmakos which means medicine or drug; and logos which means study). In actual use, it's meaning is limited to the study of how drugs and other substances affect our bodies. It has been defined as an experimental science which studies how substances that have entered our bodies affect our organism. The main tasks of pharmacologists are screening for desired activity, determining mode of action, and quantifying drug activity when chemical methods are not available.[1]