1.0 OBJECTIVE:
To
lay down the calibration procedure for reliable and accurate results.
2.0 SCOPE:
This
shall be applicable to the pH
meter of Quality Control Laboratory.
3.0 RESPONSIBILITY:
3.1
Technical Assistant/
Helper.
3.2
Q.C Analyst.
4.0 ACCOUNTABILITY:
4.1
Manager-Quality
Control.
5.0 MATERIAL AND
EQUIPMENT:
5.1
Polarimeter.
5.2
Desiccator.
5.3
Magnetic stirrer.
5.4
Glassware (6
beaker of 100.0ml, 1 stirrer, spatula).
5.5
Tissue paper.
5.6
Standard refined
sucrose previously dried at 105oC for 3 hours.
5.7
Acetone.
5.8
Purified water.
6.0 PROCEDURE:
6.1
Switch ON the
mains.
6.2
Operate the
Polarimeter according to the SOP
6.3
Wait till sodium
lamp glows with full intensity of yellow light.
6.4
Rinse the
Polarimeter tube with distilled water.
6.5
Adjust the vernier
scale and main dial scale to zero.
6.6
If two halves
intensity is not metering then adjust it by turning knurled screw of the prism
box slightly. If not possible then adjust the field by rotating milled knob and
vernier scale note the reading (+) or (-) side as a zero and to be consider
while calibrating.
6.7
Fill the purified
water in Polarimeter tube.
6.8
Clean the sides of
the tube with tissue paper.
6.9
Entrap any air
bubble in space at center of the tube.
6.10 Keep
the Polarimeter tube in the place provided in the Polarimeter.
6.11 Adjust
the zero with the help of control wheel.
6.12 Focus
circular disc of light with the help of field telescope.
6.13 Observe
the field, which is divided into two halves, light and dark.
6.14 Adjust
the control wheel to get equal intensity of the two halves.
6.15 Measure
optical rotation of the blank solution.
6.16 Note
the + or – reading in degree of rotation.
6.17 Repeat
the step no. 6.5 to 6.15 for 5 times.
6.18 Take
average of the 5 readings.
6.19 Remove
the Polarimeter tube from Polarimeter & discard the purified water from the
tube.
6.20 Prepare
10%, 20%, 30%, 40% & 50% solution in purified water of standard refined
sucrose previously dried at 105oC for 3 hours.
6.21 Rinse
the tube with 10% solution and fill the solution in Polarimeter tube.
6.22 Clean
the sides of the tube with tissue paper.
6.23 Entrap
any air bubble in the space at the centre of tube.
6.24 Keep
the Polarimeter tube in the space provided in the Polarimeter and measure the
optical rotation of sample solution.
6.25 Note
the reading in degree of rotation.
6.26 Repeat
the operation 5 times and record the readings.
6.27 Remove
the tube from Polarimeter & discard the solution from the tube.
6.28 Repeat
the operation with 20%, 30%, 40% & 50% solution after rinsing with the same
solutions.
6.29 Note
the readings of each concentration.
6.30 Remove
the tube from Polarimeter and discard the solution from the tube.
6.31 Wash
the tube from Polarimeter and discard the solution from the tube.
6.32 Wash
the tube with purified water and rinse with acetone and keep in Polarimeter
tube box.
6.33 Switch
OFF the mains.
6.34 Enter
the calculated readings in calibration record.
6.35 Record
the result on the “Calibration Record”,
“Calibration Log Book” & paste the “Calibration
Status Sticker” on Polarimeter.
6.36 Acceptance
criteria (if any):
6.36.1 Difference
between std. value and calculated value must not be more than 0.05o
for 10% & 20% and not more than 0.1o for 30%, 40% & 50%
solution.
6.37 If
the value does not meet the acceptance criteria, inform the QA/QC manager for
further action.
6.38 Frequency of
calibration: Monthly or after any maintenance.
6.39 Precautions:
6.39.1 Polarimeter
tube should be filled in such a way so as to avoid air bubbles.
6.39.2 Before
taking the reading clean the Polarimeter tube with tissue appear.
6.39.3 Set
the field telescope for better observation.
6.39.4 The
optical elements must be cleaned and at exact alignment.
6.39.5 Tighten
the end plate with caps and seal so as to make it leak proof.
7.0 REVISION LOG:
|
Revision No.
|
Effective Date
|
Reason
|
|
00
|
|
New
SOP
|
8.0 REFERENCES:
8.1 Not Applicable.
9.0 ANNEXURES:
Annexure 1:
Calibration sheet of Polarimeter.
Annexure:
1
Calibration
sheet of Polarimeter
|
Calibration of
Polarimeter
Instrument:
___________________ Date:
_______________
Model:
_______________________ Length
of Polarimeter tube: ________________
Calibration solution: Sucrose
solution of different concentration.
Blank solution: Purified
water.
Blank
solution:
Average: _________________________
*Specific optical rotation
of blank solution by using formula:
[α]λ
T = α/lc
Sample
solution:
*Specific optical rotation
of sample solution by using formula:
[α]λ
T = α/lc
* Difference between
std. value and calculated value must not be more than 0.05o for
10% & 20% and not more than 0.1o for 30%, 40% & 50%
solution.
|
10.0
ABBREVIATIONS:
|
Abbreviation
|
Expanded Form
|
|
SOP
|
Standard operating
procedure
|
|
&
|
And
|
|
No.
|
Number
|
|
Ltd.
|
Limited
|
|
Q.C
|
Quality control
|
|
Q.A
|
Quality assurance
|
|
QCEB
|
Quality control
equipment calibration
|
|
F
|
Format
|
|
oC
|
Degree centigrade
|
|
ml
|
Milliliter
|
|
%
|
Percentage
|
|
o
|
Degree (angle)
|
|
l
|
Length
|
|
g
|
Grams
|
|
c
|
Concentration (g/ml)
|
|
α
|
Alpha (here it is denoted
as observed optical rotation)
|
|
λ
|
Lambda
|
|
T
|
Temperature
|
|
[α]λ T
|
Specific optical
rotation
|
|
Sr.#
|
Serial number
|