Firast, Inject sires of calibration solutions (minimum 4) using same procedure and, record peak area (or peak height) at selected wave length.

These four levels should be withing the calbration range

Plot peak area (or height) verses concentration (use Excel sheet).

create the calibration curve ( Y= mX +C)

Where, Y - peak area (or height), X - Concentration of Drug

You can get the values for m and C from the graph

Then, get the peak area (or height) of your unknown sample. you can get this value from HPLC chromatogram ( you know now, Y,m and C)

So, now, now you can calculate X (concentration of unknown solution of the drug)

For good results, correlation coefficient (R ) of your calibration curve should not less then 0.996.

to calculate MDL, Refer the document attached

put the value of AUC (area under curve) to the formula of assay according to individual drug`s monograph, and calculate the assay.

dont forget to delete peaks of solvent system used before calculation.

Firast, Inject sires of calibration solutions (minimum 4) using same procedure and, record peak area (or peak height) at selected wave length.

These four levels should be withing the calbration range

Plot peak area (or height) verses concentration (use Excel sheet).

create the calibration curve ( Y= mX +C)

Where, Y - peak area (or height), X - Concentration of Drug

You can get the values for m and C from the graph

Then, get the peak area (or height) of your unknown sample. you can get this value from HPLC chromatogram ( you know now, Y,m and C)

So, now, now you can calculate X (concentration of unknown solution of the drug)

For good results, correlation coefficient (R ) of your calibration curve should not less then 0.996.

to calculate MDL, Refer the document attached

Firast, Inject sires of calibration solutions (minimum 4) using same procedure and, record peak area (or peak height) at selected wave length.

These four levels should be withing the calbration range

Plot peak area (or height) verses concentration (use Excel sheet).

create the calibration curve ( Y= mX +C)

Where, Y - peak area (or height), X - Concentration of Drug

You can get the values for m and C from the graph

Then, get the peak area (or height) of your unknown sample. you can get this value from HPLC chromatogram ( you know now, Y,m and C)

So, now, now you can calculate X (concentration of unknown solution of the drug)

For good results, correlation coefficient (R ) of your calibration curve should not less then 0.996.

to calculate MDL, Refer the document attached

How could you use TLC for measuring drug concentration, or would this be used for seeing the stability of the drug in an extemporaneous preparation 

Different methods are used e.g. internal standard(single point or a calibration curve)

External standard( single point or a calibration curve))

Standard addition method(different methods)

 area normalization  and finally there are different formulae that you can use to quantify a drug by using HPLC.  I advice you to read a decent book so that you know the pros and cons of each method

Area or height to be considered for calculations?

Standard curve of drug was formulated according to straight line equation.

y = mx+ c                                                                                                                        (1)

Where,

y = area of the sample (mAU*min)

m = slope

c = intercept

x = concentration of unknown sample (mg/kg)

m and c were obtained from specific drug’s standard curve and y is the area obtained from detected drug in the sample.

Therefore, the equation is

x = (y-c)/m                                                                                                                 (2)

Where,

y = area covered by antibiotic in sample (mAU*min)

m = slope of standard curve

c = intercept of standard curve

x = residual concentration of antibiotic in sample (mg/kg)

If it is dissolution profiling then it has to be calculated by calibration curve method linear graph.

Hi everyone, im currently using HPLC to detect ester (ascorbyl palmitate) produced by enzymatic synthesis.

I already know the concentration of them using standard calibration curve applying the equation y=mx+c to get the concentration of ascorbyl palmitate.

What I am trying to do now is to check on the conversion yield in % of my product.

Is what I am doing the correct way.

1) Get standard calibration curve for ascorbic acid which is the one of the susbtrate.

2) Determine the concentration of ascorbic acid in the sample which is at the end of reaction.

3) Using the formula

Conversion yield(%)= (Xo-Xf/Xo)*100

where xo = [ascorbic acid at start of reaction]

xf = [ascorbic acid at end of reaction/from sample]

Could some please help me wheater my method is right to be used. Im new to this field so I am keen to know more and please help me.Thank you everyone.

http://www.chromacademy.com/lms/sco9/Theory_Of_HPLC_Quantitative_and_Qualitative_HPLC.pdf

you can refer to this document, it is very helpful

https://www.chromacademy.com/lms/sco9/Theory_Of_HPLC_Quantitative_and_Qualitative_HPLC.pdf

Dear all,

Kindly clarify the issue. What is base of Use of main peak LOQ value in unknown impurities calculation.