Introduction:
Biological assays or bioassays are scientific experiments utilized to test effects of the compound on living organism, and are necessary in drug developments and monitoring of environmental pollutants. Sensitivity tests are laboratory methods utilized to find out vulnerability of microorganisms to drug therapy.
Drug Bioassays:
Many drugs are isolated from natural products, and consequently pharmacological screening or evaluation is essential to guide isolation procedure towards production of the pure active bio-component. Bioassays find out concentration of purity or biological activity of substances like hormones and plant extracts, whereas measuring effects on the organism or tissue cells compared to the standard preparation. The objectives of drug bioassays are; measurement of pharmacological activities of new or chemically undefined compounds, investigating functions of endogenous mediators, to know side effects of drug to be used, and concentration measurement of known substances. Drug bioassays are generally quantitative, in that they compute biological response evoked by the use of such drugs, and they are generally analyzed using biostatistics. The drug bioassay may be primary or secondary assay depending on specific criteria like cost and duration of results. The primary bioassay may not be quantitative, and is applied to the large number of samples; it is cheap and generates results rapidly. While secondary bioassays are applied to more thorough samples, are slow and costly. The primary bioassay must meet certain criteria like:
There are four approaches which act as bioassay guide in drug discovery research, and the choice of screening approach depends on target disease and available information about the target organism to be studied. The approaches are as follows:
i) Use of the single bioassay method to search for the specific kind of pharmacological activity like anti-inflammatory activity
ii) Use of specific bioassay method, with each procedure designed to capture specific helpful properties
iii) Use of single bioassay method to discover numerous activities
iv) Use of the variety of combination of bioassays to notice specific and numerous activities.
There are essentially two kinds of bioassays; Quantal and Graded. The quantal bioassay needs all or none response that has no room for intermediate results. In case of toxicity studies, animal receiving drug either dies or not. Graded bioassay is based on the observation that, balanced increase in dose levels causes a similar increase in response. Methods involved in determination of bioassays are:
i) Matching bioassays: Simplest kind of bioassay and it involves taking the response of first substance and then matching it with standard response. This technique is applied to small sample sizes and major limitation is that it doesn't take into consideration sensitivity of drug; therefore it is not precise or reliable.
ii) Interpolation method: This is performed by finding amount of preparation of unknown potency needed to produce the definite effect on appropriate tissues or test animals under the standard condition, and effect is compared to standard.
Drug Sensitivity Tests:
When the microorganism has been recovered from the clinical specimen, it is cultured and tested against the variety of drugs. If the growth of the microbe is reserved by action of the drug, it is reported as being responsive to the drug, but if actions of the drug have little or no effect on the development of the microbe, the microbe is reported to be resistant to the drug. This procedure is called as drug sensitivity test, and culture utilized in this test is dependent on kind of microorganism. Drug sensitivity tests assists to give information about strength of certain drugs, if they are still efficient and to what extent if they are. Without drug sensitivity tests, drugs are prescribed on the trial and error basis, that could take several days for the observed improvement and at times may lead to numerous complications during course of illness like kidney impairment, or even lead to death of patients. Culturing microorganisms before testing for drug sensitivity is done to allow reproduction and development of the microbe for simple identification of results. It generally takes up to 18 hours to get results for bacteria, but it could take numerous weeks to examine colonies in bacterium which causes tuberculosis. Culture mediums are generally sterile plastic dishes having nutrient gel on which they feed, and at times substances are added to medium to suppress the development of other bacteria not required. Though, viruses need living cells to grow. After culturing, the small portion of colony is removed and stained for proper recognition under microscope. Once properly recognized, drug sensitivity test is performed by inserting paper discs having drugs of specification, in bacteria culture medium. Medium is checked after 24 hours to examine the drug which bacterium is most sensitive to.
Tutorsglobe: A way to secure high grade in your curriculum (Online Tutoring)
Expand your confidence, grow study skills and improve your grades.
Since 2009, Tutorsglobe has proactively helped millions of students to get better grades in school, college or university and score well in competitive tests with live, one-on-one online tutoring.
Using an advanced developed tutoring system providing little or no wait time, the students are connected on-demand with a tutor at www.tutorsglobe.com. Students work one-on-one, in real-time with a tutor, communicating and studying using a virtual whiteboard technology. Scientific and mathematical notation, symbols, geometric figures, graphing and freehand drawing can be rendered quickly and easily in the advanced whiteboard.
Free to know our price and packages for online biology tutoring. Chat with us or submit request at [email protected]
tutorsglobe.com estimation of future cash flows assignment help-homework help by online capital budgeting and project planning tutors
tutorsglobe.com benefits of cross pollination assignment help-homework help by online cross pollination tutors
Avail impeccable Protozoology Assignment Help and score excellent marks with 24x7 support of PhD experts at competitive prices.
Biology tutorial tutorial all along with the key concepts of Development of Sperm, Development of the egg, Gamete Interaction, Sperm-egg fusion, Egg activation and pronuclei formation, formation of gametes, zona pellucida and spermiogenesis
tutorsglobe.com internal economies of scale assignment help-homework help by online internal economies tutors
Having set out the major principles included in preparing an income statement, we required to consider some additional points.
tutorsglobe.com xeric habitats characterization assignment help-homework help by online xerophytes tutors
tutorsglobe.com decarboxylation assignment help-homework help by online metabolism of proteins tutors
Get the optimum E-Business Assignment Help service from top experts at low prices and excel your academic grades!
We bring to you industry best Global Change-Issues and Impacts Assignment Help tutors round the clock to help you to score A++ grades!
free act study guide, act test papers, act practice papers, act test pattern and general information, find act exam information and resource, material free at tutorsglobe.com
Chemistry of lipids tutorial all along with the key concepts of Chemical composition of lipids, Kinds of fatty acids, Properties of fatty acids, Physical property of fatty acid, Chemical properties of fatty acid and Nomenclature of fatty acids
A meristematic tissue (meristos = divisible) is a group of similar cells which are in a continuous state of division.
www.tutorsglobe.com offers acidity of carboxylic acids homework help, acidity of carboxylic acids assignment help, online tutoring assistance, organic chemistry solutions by online qualified tutor's help.
tutorsglobe.com zinc carbonate assignment help-homework help by online compound tutors
1952010
Questions Asked
3689
Tutors
1484107
Questions Answered
Start Excelling in your courses, Ask an Expert and get answers for your homework and assignments!!