Analytical Development
Effect of pH in Analytical Method
As a chromatographer not many of us are aware of how critical pH is in your method development, sometimes it is even considered as an inconsequential factor, which could have a negligible effect on our analysis. However, in truth pH can make or break your analysis, choosing the correct or ... Read More
Media and Buffers in Dissolution Method Development
Sink Conditions: Volume of medium should be at least 3 times that needed to form a saturated solution (USP definition). pH Range: Typical range is 1.1 to 6.8, but can be adjusted up to pH 8.0 for solubility. Common Buffers: Surfactants: Medium Deaeration: Ensure medium is deaerated to prevent bubbles, ... Read More
Discriminating Dissolution Media
Discriminating Dissolution Media is a critical component in pharmaceutical formulation development, designed to identify differences in the dissolution performance of drug products. These media are particularly useful when addressing formulation changes, variations in API properties, or manufacturing process alterations. Key Features of a Discriminating Dissolution Medium Examples of Common Discriminating ... Read More
Cetylpyridinium Chloride (CPC) in Dissolution Bath
Cetylpyridinium chloride (CPC) at 0.01% w/v is often used in a dissolution bath to maintain microbial control and ensure the cleanliness of the system. Its inclusion helps prevent microbial contamination, which could interfere with the dissolution process and affect the accuracy of drug release studies. CPC is a cationic surfactant ... Read More
Difference Between C8 and C18 Columns
C8 and C18 are both types of reverse-phase chromatography columns, but they differ in their: Carbon chain length: Hydrophobicity: Retention characteristics: Separation range: Column selectivity: In summary, C8 columns are used for smaller, more polar molecules, while C18 columns are used for larger, more non-polar molecules. The choice between C8 ... Read More
Surfactants in Dissolution
We have many factors to consider when making a dissolution method. What apparatus, speed, filter choice, etc. Of these factors, the one I get the most questions about is media selection – especially surfactants in media selection. So, what is a surfactant and why do we use them? What do ... Read More
Base Line Noise in HPLC
While performing HPLC analysis with an existing method, sometimes we will observe more base line noise. However, we won’t observe that scenario previously. The major probability due to: About dirty mobile phase: Grade of organic solvet used for analysis. Especially In case of THF is there in mobile phase we ... Read More
Role of pKa and pH Values in HPLC
One of the critical factors influencing the success of an HPLC analysis is the control of pH, which directly impacts the ionization state of analytes. The pKa value of a compound, indicating its acid dissociation constant, plays a pivotal role in this process. pKa: A Key Parameter The pKa value ... Read More
Forced Degradation Studies During Method Validation
During method validation, the FDA expects forced degradation studies to be conducted to assess the stability-indicating capability of the analytical method. These studies involve subjecting the drug substance or product to various stress conditions (e.g., heat, light (Day and UV light), acid/base hydrolysis, oxidation) to induce degradation. By monitoring changes ... Read More
Different Types of HPLC Columns in Pharmaceutical Analysis
In High-Performance Liquid Chromatography (HPLC), the choice of column is crucial for successful separation and analysis. Let’s explore the different types of HPLC columns: Normal Phase HPLC Columns Stationary Phase: These columns have a more polar stationary phase than the mobile phase. Silica gel, a polar material, is commonly used ... Read More
Importance of pKa Value in Selection of Dissolution Media
There is a question: How pKa value helps in selection of Dissolution Media during Formulation & Analytical Development? For Dissolution, Ionized form of a drug is required to be solubilized & released passively into dissolution medium. While, For Absorption, only unionized form of drug is important to be absorbed passively ... Read More