Principle of serial dilution

An instructional video to explain how to prepare a serial dilution of a broth culture of e. Received 9 may 2014 received in revised form 29 august 2014. The volume is determined via the dilution principle using this concentration at zero time. Pdf estimation method for serial dilution experiments. Since the dilution fold is the same in each step, the dilutions are a geometric series constant ratio between any adjacent dilutions. In homeopathy, serial dilutions called potentisation are often taken so far that by the time the last dilution is completed, no molecules of the original substance are likely to remain. A serial dilution is any dilution in which the concentration decreases by the same factor in each successive step in serial dilutions, you multiply the dilution factors for each step. Serial dilution of the antibiotic are made in agar and poured onto petri dishes. When greatly diluted the speciman contains only few organisms of only one species. Robert koch, singlecolony isolation, and kochs postulates. Sop for preparation of culture dilutions for analysis standard operating procedure to prepare the microbial culture suspension dilution to use the microorganisms in positive controls. In this method, an absorbent plastic strip with a continuous gradient of antibiotic is immobilized on one side.

A common design for estimating the concentrations of compounds in biological samples is the serial dilution assay, in which measurements are taken at several different dilutions of a sample. A small amount of serum or solute can be serially diluted by transferring aliquots to diluent. Prepare the dilution of the test sample expected to contain between 30300 cfuml. Spread plate technique principle, procedure and uses. Extrapolation back to zero time allows estimation of the virtual concentration at this time. A drop of this solution is taken and diluted in 99 times its own volume of liquid and shaken. Estimation method for serial dilution experiments avishai bendavid a. On the use of the serial dilution culture method to. Principles of dilution the different forms of dilution.

Based on the principle of disc diffusion, is an automated system for measuring mic of a bacterial isolate. The easiest method is to make a series of 1 in 10 dilutions. Calculate the final dilution ratio in a serial dilution. Serial dilutions tube method principle serial dilution is a common technique used in many immunologic procedures. The original culture suspension is diluted more one time serial dilution, in tubes or in appropriate medium.

Follow serial dilution technique inoculate labeled empty petri dish with specified ml 0. Serial dilutions are often performed in steps of 10 or 100. In principle, all replicated tubes expected to have. Serial dilution protocol pdf it is a method of diluting a stock solution where concentration decreases by the same quantity in each successive step. Standard bacterial plate count uncontrolled copy 3. Information and translations of serial dilution in the most comprehensive dictionary definitions resource on the web. Sop for preparation of culture dilutions for analysis.

Since the dilutionfold is the same in each step, the dilutions are a geometric series constant ratio between any adjacent dilutions. Dilution and concentration theory dilution and concentration theory sounds ominous but you use dilutions and concentrations fairly frequently outside of your scientific life. This requires a working knowledge of the principles of diluting, dilution factors, concentration factors and. The method maintains this accuracy even in the presence of dilution errors of up to 10% for both the aliquot and diluent volumes, microbial counts between 104 and 1012 colonyforming units. Serial dilutions are made by making the same dilution step over and over, using the previous dilution as the input to the next dilution in each step. Label 2 or 3 refer to the firms outline of production op plates per dilution series for each serial. This can be mathematically illustrated with the equation dt d1 x d2 x d3 x x dn where dt is the total dilution factor and dn is the dilution. A serial dilution is a series of sequential dilutions used to reduce a dense culture of cells to a more usable concentration. In other words, if the product is having too much bacterial count which is nearly uncountable, in that case also serial dilution is useful. Davidsonb a rdecom, edgewood chemical biological center, aberdeen proving ground, md 21010, usa b science and technology corporation, belcamp, md 21017, usa article info abstract article history. This is a first order process ie exponential decline which gives a straight line when plotted on a logarithmic scale. Robert koch, a german physician, is famous for determining the bacteria responsible for anthrax and tuberculosis.

Dilution tests for antibiotic sensitivity testing broth. The total dilution ratio can be determined by multiplying the dilution factor of each step leading up to the final step. Serial dilution is often a difficult concept for students to understand. In this short dry lab exercise, students perform serial dilutions using seed beads. At higher dilutions, negative scores become more likely until at very high dilutions calculated concentration dictionary.