HPLC Method Development Case Studies

Case Study 1

Development of a stability indicating RP-HPLC method for a synthetic pentasaccharide and its impurity.

Problem:

A pharmaceutical manufacturer of a synthetic pentasaccharide was having difficulty in developing a stability indicating method. Since the compound did not have any chromophores the client had attempted the development of a RP (Reverse Phase) HPLC method employing an electrochemical detector. This approach provided difficult.

 Solution:

Quantex was retained to develop a method. Our scientists developed a RP- HPLC method using an Evaporative Light Scattering Detector (ELSD). The method was able to perform the assay of the pentasaccharide and its impurity without difficulty.

  • Quantex scientists determined that a suitable approach was the development of an RP HPLC method using ELSD;
  • The developed method overcame problems with using an electrochemical detector;
  • The method was developed and optimized for the separation and quantitation of the synthetic pentasaccharide and its impurity;
  • The method was then validated and demonstrated to be linear, accurate, precise, specific and robust;
  • The method was demonstrated to be stability indicating.

Case Study 2

Development of a stability indicating method for and OTC sunscreen product containing multiple active components.

Problem:

An OTC products manufacturer was employing 2 to 3 separate methods to performing in process and finished product release testing for its sunscreen products. A single method capable of analyzing all 7 actives was sought.

Solution:

After discussions with the client, Quantex scientists suggested that a gradient RP-HPLC method was a good approach. A method was developed employing a shell core RP column with a gradient elution program. The developed method allowed for the complete separation of each of the 7 organic sunscreen actives in under 15 minutes.

  • Quantex scientists determined that a suitable approach was the development of a gradient RP HPLC method using a shell core LC column;
  • The method was developed and optimized for the separation and quantitation of all seven (7) organic sunscreens;
  • The method was then validated and demonstrated to be linear, accurate, precise, specific and robust;
  • The method was demonstrated to be stability indicating.

Case Study 3

Development of a Size Exclusion Liquid Chromatography Method to Determine the Molecular Weight and Degree of Polymerization of Dextrins.

Problem:

A manufacturer of dextrins used in pharmaceuticals, nutritional supplements and foods had need of the ability to determine the degree of polymerization up DP12. Most HPLC methods available could only provide resolution to DP7.

Solution:

Quantex scientists developed a size exclusion HPLC method for dextrins to separate and measure the degree of polymerization up DP12. The method also allows the determination of the distribution of specific molecular weights.

  • Quantex scientists determined that a suitable approach was the development of a size exclusion HPLC method;
  • The developed method allowed for the determination of DP1 to DP12 for dextrins;
  • The method was developed so that  either refractive index (RI) or evaporative light scattering (ELSD) detectorscould be used for measurement;
  • The method was then validated and demonstrated to be linear, accurate, precise, specific and robust;
  • The method provided the flexibility required by the client.

 

Case Study 4

Support for an ANDA CMC Submission by Performing a Comparative Study of a Client’s In-House Method Performance To That of the USP Monograph Method for Impurities.

Problem:

A Client had developed an in house method to carry out the analysis for impurities of an antibiotic employing detection by UV. A comparative study was needed to demonstrate equivalence to USP’s method for those impurities. The USP method employed the use of a dual electrode coulometric detector. An HPLC method with Coulometric detection can be extremely troublesome and challenging to use. Such a method requires a significant amount of experience and expertise with this specific detector.

Solution:

Quantex has extensive experience and expertise in the use of electrochemical detectors, such as coulometric and ampeometric detectors. The client was aware that Quantex scientists had aided in the development of such a method, which was subsequently included in USP 24.

The client engaged Quantex to perform the comparison. Quantex developed a study protocol which was reviewed and approved by the client. To start, our scientists conducted a method transfer study of the client’s in-house method.  With the successful transfer of the client’s in-house method,  our scientists then carried out   a verification study on the USP method. At the successfully completion of the verification study, three batches  of the antibiotic were analyzed for impurities by both methods. The comparative study demonstrated equivalence to the USP method. At the conclusion, a detailed report was developed covering the method transfer, verification and comparative studies. The report with supporting data was submitted as part of the client’s filing with FDA.  The Client has subsequently received approval for use of its in-house method.