Pharmaceutical analysis is a branch of chemistry, which deals with the study of various processes that are involves- the identification, determination, quantitation and purification. It is mainly used for the separation of the components from the mixture and for the determination of the structure of the compounds that make up pharmaceuticals, and are combined to make up a pharmaceutical product. Pharmaceutical analysis relates to the analysis of raw materials and pharmaceutical formulations, includes determination of ingredients, impurities, excipients, and uniformity, solubility, and dissolution rate to identify active components, contaminants and impurities.
Scope of pharmaceutical analysis
Pharmaceutical Analysis is one of the most sought-after masters of pharmacy specializations. Pharmaceutical analysts are critical to the manufacturing, quality control, and analytical manifestations of the industry. They can work in the quality control department, which oversees the purity, qualitative aspects, and the finished product’s compliance with stringent regulatory limits. The results of new compound analysis and detection are greatly influenced by research and development. A separate analytical R&D department is becoming increasingly important in businesses. Pharmaceutical analysis students can also find work in medical device companies, equipment companies, regulatory agencies, and so on.
Remember that no matter what compounds you discover or formulation you create, nothing is valid until it is evaluated, analyzed, and validated.
Different techniques of analysis
Analytics plays an important role in every stage of the drug development. Understanding the physical and chemical stability of drug can facilitate the selection of design of the dosage form. There are various techniques of pharmaceutical analysis which can be divided into two major categories. One is Qualitative analysis and second is Quantitative analysis.
Quality of pharmaceuticals is based on the pharmacopeial specifications. These methods are designed to set the permissive limits of tolerance for the product when it reaches the patient.
Qualitative analysis involves various test procedures that are designed for the identification of compounds in the given sample. These test results confirm the presence or absence of a compound in the sample given to be analyzed.
Examples- Colour test, melting point and boiling point determination for identification, limit test, precipitate formation, etc.
Quantitative analysis involves the quantitative determination of compounds in the sample. The procedures of quantitative analytical chemistry are applied to the analysis of materials used in pharmaceuticals. It is very important to get the information about qualitative and quantitative composition of substances and chemicals that is to find out what substance is composed of and exactly how much.
There are various methods of Quantitative analysis. Generally, the components are related characteristically to some physical property and on the basis of that the quantity is calculated. Furthermore, they are classified into:
2.Physico-chemical Method or Instrumental Method
A) Volumetric methods
Volumetric method is also called titrimetric method are preferred over gravimetric method specially because of speed and convenience. In this method the assay is based on the measurement of volume of solution of known strength that is required to react completely with the substance to analyzed.
Depending on the type of reactions involved in the reaction volumetric method is further classified into different types, Neutralization titrations, non-aqueous titrations, Precipitation titrations, Oxidation-reduction titration and Complexometric titrations.
B) Gravimetric methods
Gravimetric method is a quantitative method of analysis involves weight and it is a process of isolating and weighing the compound of known composition in purest form.
The process of separation of compounds is done by using various methods like precipitation, volatilization, electroanalytical etc. Among these methods precipitation and volatilization are most widely used in practice. Gravimetric analysis is a time-consuming method and the constituents may be further examined for impurities and correction if needed.
C) Gasometric methods
Gasometric methods involve measurement of the volume of gases, the measurement of volume of gas is made in the gas burette or by using nitrometer. In this they measure the volume of gas liberated in the given chemical reaction under the conditions that are described in the process, the volume of gas measured is corrected to standard conditions of temperature and pressure. Decreases in the volume of gas when a suitable agent is placed to absorb one of the gases present and reduced to standard conditions of temperature and pressure.
Some examples of gases which are determined by gasometric analysis in Pharmacopoeia are, carbon dioxide, nitrous oxide, cyclopropane, oxygen, nitrogen etc.
2.Physico-chemical or instrumental methods
These methods are based on the relation between the content and corresponding physicochemical and physical properties of the chemical system to be analysed. The changes in the properties of the system detected through the measurement of current, potential, electrical conductivity, optical density and much more by using a suitable instrument.
|Mass to charge ratio
|Rotation of plane polarized light
|Polarimetry, Optical rotatory dispersion
|Absorption of radiation
Atomic absorption spectroscopy
|Refraction of radiation
|Scattering of radiation
|Emission of radiation
|Emission spectroscopy, Flame photometry, Fluorimetry
Apart from the above methods, the chromatographic methods are also available. Chromatography is a separation technique by which a mixture of a substances is separated into various components. These methods are also used for the identification and quality control in pharmaceuticals.
Microbiological methods are very important in resolving doubts regarding the possible loss of potency of antibiotics and their preparations. The inhibition of microbial growth under the standardized conditions may be utilized for knowing the therapeutic efficacy of antibiotics. Any change in the antibiotic molecule which may not be detected by chemical methods will be revealed by a reduction in antimicrobial activity and therefor microbiological methods are very important.
The microbiological method is based on the comparison between the inhibition of growth of bacteria and measured concentration of antibiotics to be examined with that produced by known concentration of standard preparation of the antibiotic having known activity. The methods used are cylinder plate method and turbidimetric method, they are also called cup plate or tube methods respectively.
When the potency of a drug or its preparation cannot be perfectly determined by chemical or physical method then biological methods are useful where to observe the biological effect of the drug on living matter.
This method is used to compare how much of the sample being tested produce the same kind of biological effect as a given quantity of standard preparation. It is also important to maintain the same conditions for sample to be tested and standard preparations in all aspect of time, environmental factors and biological media used.
However, it is very difficult to maintain the perfectly matching conditions, the biological responses vary to different extent and in biological methods it is necessary not only to estimate the potency of drug but also to estimate the margin of error is important.
The analysis of drug substances involves a range of techniques, including spectroscopic methods, chromatographic methods, and thermal analysis.
Spectroscopic methods, such as infrared (IR) spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy, are using to identify and quantify the active pharmaceutical ingredient and any impurities present.
Chromatographic methods, such as high-performance liquid chromatography (HPLC), gas chromatography (GC), and ion chromatography (IC), can use to separate and quantify the components of a sample.
Thermal analysis techniques, such as differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), are help to determine the thermal behaviour and stability of the drug substance.
Finally, pharmaceutical analysis is an important part of drug development and manufacturing. It refers to a variety of analytical techniques and methods used to ensure the safety, efficacy, and quality of pharmaceutical products. Pharmaceutical analysis sub-disciplines such as drug substance analysis, drug product analysis, method development and validation, quality control and quality assurance, and regulatory compliance all play important roles in ensuring that drugs are safe and effective for patient use.
The ongoing development and application of analytical techniques in pharmaceutical analysis is critical to ensuring that drugs are of the required quality and are safe to use.
Frequently ask questions
What is pharmaceutical analysis?
Pharmaceutical analysis is a branch of chemistry, which involves the series of process for the identification, determination, quantitation, and purification.
What is the scope of pharmaceutical analysis?
It is mainly used for the separation of the components from the mixture and for the determination of the structures of the compounds. Pharmaceutical analysis students can also find work in medical device companies, equipment companies, regulatory agencies, and so on.
What are the 4 major purposes of pharmaceutical analysis?
The 4 major purposes of pharmaceutical analysis are:
- Classification of a compound according to its chemical properties.
- Analysis of mixtures for compounds.
- Separating components from mixtures.
- Purification, identification and characterization of compounds.
What are the different techniques of quantitative analysis?
Following are the methods for quantitative analysis:
2.Physico-chemical Method or Instrumental Method