Preparation of standard curve.pptx

This PowerPoint presentation provides a thorough grasp of standard curve preparation. Through detailed explanations and illustrative visuals, viewers will gain a comprehensive understanding of the process, enabling them to confidently apply this essential technique in their scientific endeavors.

1. Md Shahjahan Kabir B.Sc. In Food and Process Engineering MS in Food Processing and Preservation (1 st semester) Hajee Mohammad Danesh Science and Technology university, Dinajpur Construction of standard curve

2. Standard Curve The standard curve is a graphical representation of the relationship between the concentration of the analyte and the corresponding signal response generated by the analytical instrument. Standard curve preparation is a fundamental technique in analytical chemistry used to relate the concentration of an analyte (substance being analyzed) to a measurable signal, such as absorbance, fluorescence intensity, or electrical current.

3. Standard Curve The standard curve is typically prepared by measuring the signal response (e.g., absorbance) of a series of standard solutions with known concentrations of the analyte. These standard solutions are prepared by diluting a stock solution of the analyte to create a range of concentrations. The signal responses obtained from these standard solutions are then plotted against their respective concentrations to generate the standard curve

4. Importance of standard curve preparation Quantification: Standard curve preparation allows for the quantification of unknown concentrations of the analyte in samples by comparing their signal responses to those obtained from the standard solutions. Calibration: Standard curves serve as a calibration tool for the analytical instrument. They ensure that the instrument is operating accurately and reliably within the linear range of measurement.

5. Importance of standard curve preparation Quality control: Standard curves provide a means for assessing the precision and accuracy of analytical methods. Deviations from the standard curve may indicate problems with the instrument or the analysis technique. Validation: Standard curves are essential for validating analytical methods, particularly in research and regulatory settings. They demonstrate the linearity, sensitivity, and range of the analytical method.

6. Importance of standard curve preparation Comparison: Standard curves allow for the comparison of results obtained from different instruments, laboratories, or studies. They provide a common reference point for interpreting analytical data. standard curve preparation is a critical step in analytical chemistry, providing a foundation for accurate and reliable quantification of analytes in various samples.

7. Primary steps in preparation specific standard curve Identify Analytes : Determine which compounds or substances you want to analyze. These could be specific chemicals, biomolecules, drugs, or any other substances of interest. Select Standards : Obtain pure samples of the analytes you've identified. These will serve as your standard solutions. Range Determination : Decide on the concentration range you want to cover in your standard curve. This range should ideally encompass the expected concentrations of your analytes in your samples.

8. Primary steps in preparation specific standard curve Instrument Compatibility : Ensure that the analytical technique or instrument you're using is compatible with the compounds you've selected. Different compounds may require different analytical methods (e.g., UV-Vis spectroscopy, HPLC, GC-MS, etc.). Validation : Validate your standard curve by analyzing the standard solutions using your chosen analytical method. Ensure that the responses obtained are linear over the concentration range and that they accurately reflect the concentration of the analyte in each solution.

9. Preparation of stock solution Determine the volume of stock solution needed Calculate the mass of compound needed Weigh the compound Dissolve the compound Mix thoroughly Transfer to a volumetric flask Label the flask Verify concentration (optional)

10. Preparation of stock solution (Example: Total Phenol Content ) Standard (Gallic Acid) Gallic Acid = 1250 µM = 1250X10 -6 M We know that, C= (1000xW)/ (MxV) Now, W= (CxMxV)/1000 = (1250x10 -6 X170.12x10)/1000 = 0.00213g/ mL =2.13mg/mL Here, C= 1250x10 -6 M M= 170.12g V=10mL W=?

11. Preparation of stock solution (Example: Total Phenol Content ) 0.0021g Gallic Acid   Pour in 10mL Methanol   Mixing thoroughly by magnetic stirrer Preparation of Stock solution (Gallic acid + Methanol)

12. Preparation of Standard Solution {Stock Solution (Gallic acid + Methanol) + Methanol} Tube no Concentration (mg/mL) Dilution (%) Stock Solution (mL) Methanol (mL) Total volume (mL) 01 (0*2.13) =0.000 0.000 0.500 0.500 02 (0.20*2.13) =0.426 20 0.100 0.400 0.500 03 (0.40*2.13) =0.852 40 0.200 0.300 0.500 04 (0.60*2.13) =1.278 60 0.300 0.200 0.500 05 (0.80*2.13) =1.704 80 0.400 0.100 0.500 06 (1.00*2.13) =2.130 100 0.500 0.000 0.500

13. Standard Curve For TPC 0.5 ml Sample (from table) 0.5 mL FCR Vortex 5sec 1mL Na 2 CO 3 8mL Distil Water Vortex 10 sec Stand for 35 min in Dark Place Centrifuge at 4000r[pm for 10min Read absorbance in 96wellplate at 765nm

14. Absorbance Tube no Absorbance Blank Abs-Blank 0.021 0.016 Average 01 0.012 0.016 0.015 0.016 0.132 0.016 0.116 02 0.114 0.016 0.098 0.11 0.132 0.016 0.116 0.267 0.016 0.251 03 0.24 0.016 0.224 0.238667 0.257 0.016 0.241 0.388 0.016 0.372 04 0.383 0.016 0.367 0.362 0.363 0.016 0.347 0.523 0.016 0.507 05 0.524 0.016 0.508 0.497333 0.493 0.016 0.477 0.614 0.016 0.598 06 0.679 0.016 0.663 0.637 0.666 0.016 0.65

15. Concentration vs Absorbance Concentration (mg/mL) Absorbance 0.424 0.11 0.848 0.238667 1.272 0.362 1.696 0.497333 2.12 0.637

16. Standard Curve for Total Phenol Content

17. Questions

18. Thank You