Analytical Worksheet

-


The analytical worksheet is an internal document to be used by the analyst for recording information about the sample, the test procedure, calculations and the results of testing. It is to be complemented by the raw data obtained in the analysis.


Purpose

The analytical worksheet contains documentary evidence either:

  • To confirm that the sample being examined is in accordance with the requirements.
  • To support an OOS result.

Use

A separate analytical worksheet should usually be used for each numbered sample or group of samples.
Analytical worksheets from different units relating to the same sample should be assembled together.

Content

  • The analytical worksheet should provide the following information: 
  • The registration number of the sample.
  • Page numbering, including the total number of pages (and including annexes)
  • The date of the test request.
  • The date on which the analysis was started and completed
  • The name and signature of the analyst
  • A description of the sample received.
  • References to the specifications and a full description of test methods by which the sample was tested, including the limits.
  • The identification of the test equipment used.
  • The identification number of any reference substance used.
  • If applicable, the results of the system suitability test.
  • The identification of reagents and solvents employed.
  • The results obtained.
  • The interpretation of the results and the final conclusions (whether or not the sample was found to comply with the specifications), approved and signed by the supervisor.
  • Any further comments, for example, for internal information, or detailed notes on the specifications selected and the methods of assessment used, or any deviation from the prescribed procedure, which should be approved and reported, or whether and when portions of the sample were forwarded to other units for special tests and the date on which the results were received.

All values obtained from each test, including blank results, should immediately be entered on the analytical worksheet and all graphical data, whether obtained from recording instruments or plotted by hand, should be attached or be traceable to an electronic record file or document where the data are available.

The completed analytical worksheet should be signed by the responsible analyst(s), verified and approved and signed by the supervisor.

When a mistake is made in an analytical worksheet or when data or text need to be amended, the old information should be deleted by putting a single line through it (it should not be erased or made illegible) and the new information added alongside. All such alterations should be signed by the person making the correction and the date of the change inserted. The reason for the change should also be given on the worksheet (suitable procedures should be in place for amending electronic worksheets).

Comments

Post a Comment

Popular posts from this blog

What is Retention time?

-
Image
Retention time (RT) is a measure of the time taken for a solute to pass through a chromatography column. Retention time (RT) is calculated as the time from injection to detection. The RT for a compound is not fixed as many factors can influence it even if the same instrument and column are used.  These include: The flow rate Temperature differences in the oven and column Column degradation Column length What is RRT?
Read more

Relation between Resolution and Peak separation?

-
Image
The resolution is represented as a numeric value, such as 0.8, 1.0, or 3.0. But what is the relationship between the number representing the resolution and the actual peak separation?  At a resolution of 1.0, if the two peaks are assumed to have a Gaussian distribution and have the same peak height and peak width, then the difference in retention time from equation  become 1.0W, or 1.0 × 4σ = 4 σ.  In the case of a Gaussian distribution, 4 σ encompasses 95.4 %, such that the peaks overlap by 2.3 % ((100 % - 95.4 %)/2).  This indicates that 2.3 % of the peak intrudes into the other peak from a perpendicular line drawn in the trough.  Similarly, a resolution of 1.5 indicates a difference in retention time of 1.5× 4σ = 6σ, which corresponds to an overlap of 0.15 % ((100 % - 99.7 %)/2).
Read more

What is RRT?

-
Image
Relative retention time (RRT) is the ratio of the retention time of analyte peak relative to that of another used as a reference obtained under identical conditions. RRT = (T analyte / T reference)  Wher T = Retention time As per USP Relative retention time (RRT): Also known as the “unadjusted relative retention”. Comparisons in USP–NF are normally made in terms of unadjusted relative retention, unless otherwise indicated. RRT = tR2/tR1 The symbol rG is also used to designate unadjusted relative retention values. The use of the relative retention time (RRT) reduces the effects of some of the variables that can affect the retention time. What is Retention time?
Read more