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Author: Estec Marketing



Quality control tests of tablets or evaluation of tablets is a systematic determination of physical, chemical, mechanical, biological, or microbiological properties of tablets on the basis of in-house (Non-Pharmacopeial), Pharmacopeial standards such as BP, USP, Ph. Eur., Ph. Int., JP, IP, ChP, or others guidelines such as ICH etc.

A variety of methods are used for evaluation of tablets or conduct quality control tests of tablets, classified into three categories:

  1. Pharmacopeial or Official Tests of Tablets:
  2. Identification Tests – The identification test is specified in a product monograph as an aid to confirm that the tablet contains the labeled drug substance by providing positive identification of the active substance(s) and identification of specific excipient(s), such as preservatives in a drug product.
  3. Friability – Friability testing is used to test the durability of tablets during transit (packing, transportation).
  4. Disintegration – process by which a solid oral dosages form such as tablet breaks down into smaller particles or granules.
  5. Uniformity of Dosage Unit – the degree of uniformity in the amount of the drug substance among dosage units.
  6. DissolutionDissolution is the process in which a substance forms a solution. In vitro dissolution testing measures the extent and rate of solution formation from a dosage form (the amount of percentage of the drug substance in a dosage form such as tablets, capsules to go into solution) within a specific time under a specified set of conditions.
  7. Assay – crucial quality control tests of tablets. A specific and stability-indicating test to determine the potency (content) of the drug product.
  8. Impurities: Impurities in tablets are specified in an individual product monograph or may be calculated by ICH Q3B(R2) guideline.

Specific Pharmacopeial Tests of Tablets:

  1. Microbiological Examination of tablets
  2. Acid-Neutralizing Capacity
  3. Quality test of Splitting Tablets with Functional Scoring
  4. Water content

Non-Pharmacopeial or Non-Official Tests or In-House Tests of Tablet:

  1. Appearance/ Description
  2. Thickness and Diameter
  3. Hardness
  4. Organoleptic properties (color, odor, and taste)

Our products from PHARMA TEST Germany are specified to perform some of the above tests, including:

In this article, we discuss more on Dissolution Testing.

Why tablet dissolution Testing?

Tablet dissolution testing is a crucial pharmacopoeia test for the evaluation of tablets or quality control tests of tablets.

A dissolution test is a means of identifying and proving the availability of active pharmaceutical ingredients (API) in their delivered form.

A dissolution test reflects the availability of active substance and allows the prediction of the time for complete release of the material from the dosage form. This test plays an important role in product development, equivalence studies and for product compliance and release decisions. It is vital that the dissolution system provides accurate and reproducible results.

All Pharma Test tablet dissolution testing instruments are fully USP and EP compliant. They use our MonoShaft™ tool system and include a full set of vessels and USP Apparatus 2 paddles. A full range of dissolution accessories is also available.

We offer manual, offline semi-automated, and online automated dissolution systems.

Operation Principleoffline dissolution system

As soon as the samples have been inserted, the system will start its automated operation. The sampling times have been programmed via the touch screen of the PTWS 1220 dissolution bath and are saved as a specific method for subsequent tests. After the start of test, a command is sent from the dissolution bath to the PTFC-16 fraction collector and from there to the connected pump to start a sampling sequence. The EPE-1220 moves the sampling tubes and filter tips into the media to the selected sampling position.

The pump will start to fill up and pre-flush the tubing. When all tubing is filled-up, the samples are collected into vials inside the collector dish of the PTFC-16. Depending on the system configuration, after dosing the volume will be refilled and the EPE-1220 will move back out of the dissolution vessels. At the end of a cycle all the tubing is emptied. The system is waiting for the next sampling time. All vials are covered during the test; the vial dish can be easily removed. Also, special dishes are available for HPLC vials.


DFC (offline Automated Dissolution Testing Systems)

Principle Online Dissolution Testing System

The multi-channel IPC pump is used to transfer the media from the vessels to the spectrometer. The samples here are circulated in a closed loop, so that there is no sample volume loss over the time of the dissolution test. At the programmed time point the sample circulation is stopped and either a single point absorbance reading, or a full UV/VIS spectrum of each vessel is collected. The control of the entire system as well as the data handling, calculation and reporting is performed by the 21 CFR Part 11 compliant WinDiss ARGUS Software.

                                                  ADL (Online Automated Dissolution Testing Systems)


Optional WinDiss ARGUS Dissolution Software is 21 CFR Part 11 compliant as well as compliant to the new requirements for Data Integrity.

WinDiss ARGUS Dissolution simplifies how you collect and report dissolution test results by letting you choose the analysis template that matches the way you work. Whether you are in QC concerned about data integrity, compliance, and validation, or need maximum flexibility in R&D, WinDiss ARGUS Dissolution can help your lab perform more efficiently.

For more information, clarifications, and requests, feel free to contact us anytime.


Written by Pascalia Jerop – Sales Executive, ESTEC LTD

Published by Mitchelle Gacheri– Marketing Executive, ESTEC LTD


As ESTEC Ltd runs its FTIR promotion, here a few things to note about the equipment.

FTIR Explained
First, Fourier Transform Infrared Spectroscopy is a technique used to obtain an infrared spectrum of absorption or emission of a solid, liquid, or gas and in the process identify known and unknown materials/samples by utilizing Infrared Electromagnetic Radiation. An FTIR spectrometer simultaneously collects high-resolution spectral data over a wide spectral range giving it an advantage over conventional spectrophotometers.

In principle, the molecules vibrate, bonds stretch and bend when they absorb IR Radiation. This is done by passing a beam of IR light through a sample. Some of this light will be reflected while others will be absorbed by the sample and consequently specific light will travel through the sample carrying molecular information of the sample. The transmitted light then goes through a detector where the information is interpreted and transformed to a spectrum (sample spectrum). This is achieved by the Fourier Transform mathematical process hence the acronym FTIR. Identification occurs when the sample spectrum is compared to a reference/known spectrum. I know you want to ask how it happens and/or where the known spectrum is. Well wonder not…

All our FTIRs come with LabSolutions IR – An analytical Data system for FTIR. LabSolutions IR is furnished with a rich Spectral Library (Approx. 12,000 spectra of organic compounds, polymers, pharmaceutical products, inorganic compounds, food additives, contaminants, etc.) and a High-performance search function as standard.

We also offer, with our FTIR’s, Attenuated Total Reflectance (ATR) Accessory – Single-Reflection Accessory with a Diamond Crystal. The accessory enables the measurement of a wide variety of samples regardless of their form or properties. I.e., Solids, Liquids, and gels in the mid and far-infrared. Measurement is made without destroying the sample as no sample preparation is required.

As conveyed in the posters, the choice of a particular Model depends on your application, and If I may add, your future needs.


FTIR’s Comparison
Look at the table below showing the Differentiation between our FTIR series based on customer needs.

Item IRTracer-100 Affinity-1S IRSpirit
S/N Ratio 60,000:1 30,000:1 30,000:1
Wavenumber Expansion Suitable for customers with absorption of the desired component in the near or far infrared regions Suitable for customers who analyze only in the mid-infrared region Suitable for customers who analyze only in the mid-infrared region
Contaminant Analysis Suitable for customers who want to connect infrared microscope to analyze minute foreign matter or plan to add infrared microscope in the future Suitable for customers who want to connect infrared microscope to analyze minute foreign matter or plan to add infrared microscope in the future Suitable for customers who do not plan to connect infrared microscope to analyze foreign matter up to the size that can be handled.
High Sensitivity Suitable for customers who want to analyze with a highly sensitive MCT detector – used when analyzing minute or low transmittance samples. Suitable for customers who do not require an MCT detector Suitable for customers who do not require an MCT detector
Go for if you are… Research, Academic, Forensic, Environment Research, Academic, Forensic, Environment Pharma


These are just but a few points, talk to us for more details, we are happy to advise on the model that will best suit your application.

And In addition to the above, please note that we have two more new models; IRXross and FTIR Plastic Analysis System.

The Plastic Analyzer method package includes an FTIR spectral library for plastics degraded by UV rays and heat. Utilizing searches of this library demonstrates its effectiveness in the analysis of unknown samples that are difficult to identify with standard libraries. Examples include plastics degraded by exposure to UV rays as well as contaminants and defective items altered by heating.

The IRXross is a mid-level FTIR developed by downgrading IRTracer-100. Performance is almost the same as IRTracer-100 except for wavenumber expandability and S/N ratio which is 55,000:1.

Till next time…..

Written by: Serah Katini- Sales Executive, ESTEC Ltd

Published by: Mitchelle GacheriMarketing Executive, ESTEC Ltd


Liquid chromatography (LC) separates the components of a sample based on the differences in their affinity/retention strength during the stationary phase and mobile phase. Common LC techniques, namely reversed-phase, normal phase, and size exclusion chromatography. With technological advancements the LC has evolved to analyze smaller particle sizes and higher pressure that are more efficient, have higher speed, sensitivity, and resolution. This includes the high-performance liquid chromatography (HPLC) and the ultrahigh-performance liquid chromatography (UHPLC).

Upon separation by LC, the components can be detected using optical properties such as ultraviolet-visible (UV-VIS), fluorescence, refractive index, evaporative light scattering, or electrical conductivity based on the analytes’ properties. When the analyte passes through the detector, a change (e.g., increase or decrease) in the optical property will be observed and recorded.

Chromatograms obtained using these optical detectors primarily identify or qualify substances based on the retention time and quantitate substances based on the peak area and intensity. The LC chromatogram shows an example of a typical chromatogram obtained using these optical detectors. LC coupled with optical detection offers great quantitative accuracy for analytes that can be chromatographically resolved, where a detected peak comprises only a single component. However, achieving required resolution is challenging for complex samples where multiple components elute approximately at the same time. In contrast, mass spectrometry (MS) offers a highly sensitive detection technique that ionizes the sample components, separates the resulting ions in vacuum based on their mass-to-charge ratios (m/z), and measures the intensity of each ion. A mass spectrum plots the relative ion intensities against the m/z values, and a series of mass spectra are generated at each time point. This information indicates the concentration level of ions that have a given mass and is extremely valuable for the unique identification of molecules, also known as qualitative analysis. Moreover, MS provides added specificity and sensitivity, and the convenience of simultaneous multicomponent analysis.


When the LC is coupled with MS, the mass spectra obtained from these measurements provide molecular mass and structural information for eluted components, which supplement the qualitative information based on retention times obtained using other LC detectors. Therefore, LCMS combine the outstanding separation resolution of LC with the excellent qualitative capabilities of MS.

With its superior qualitative and quantitative capabilities and robustness, LCMS is commonly used to meet the rigorous demands of the analytical market and industries. LCMS is applied in many industries such as pharmaceuticals, biopharmaceuticals, forensic, industrial, food and environmental sector. For clinical research, the analysis of drugs, vitamins and minerals in whole blood, plasma, serum and urine is conducted routinely using LCMS. It is also applied in metabolomics, proteomics and genomics study. The use of LCMS in the biopharmaceutical discipline have enabled the bioanalysis and characterization of antibody drugs.


In the environmental field, LCMS is widely utilized for the qualitative and quantitative determination of known pollutants (e.g. pesticides, bacteria, pharmaceuticals and personal care products) and trace-level emerging contaminants. Food safety and development have also adopted the use of LCMS in their product quality control such as the quantitation of residual veterinary drugs, food additives and the composition analysis of supplements and organic foods. With high sensitivity, high detection selectivity and high qualitative capability, MS bring about the flexibility of simultaneous multi-component analysis, improved productivity, and efficiency to HPLC analyses in these applications.


Written By Steven Kuria – Sales Executive ESTEC Ltd 
Published By Mitchelle Gacheri – Marketing Executive ESTEC Ltd