NIR as an alternative method for lyo defect inspection

During the production, the lyo cake may not stay intact. Earlier, the customer performed the quality control by visually inspecting the cake. This inspection method is not always accurate. It is now possible to test the lyo cake spectroscopically with NIR which has no influence on the cake. NIR provides an accurate, efficient, fast and an enovirmentally friendly quality control application.

The challenge to find a defect inside a lyo cake

Human visual quality control of lyo cakes is dependent on the individual operator’s perception. Alternatively, if a camera inspection is used it is dependent on the imaging analysis technology which has also proved to be unreliable. This is often the cause of a high, unnecessary reject rate. Therefore, NIR provides an accurate, efficient, environmentally and operator friendly, quality control application which is 100% automated.

Our approach of detecting lyo cake defects with Near Infrared Spectroscopy

Our customer was experiencing a problem with their product which happened during the freeze-drying process. This is a risk to product reliability. Cake defect often occurs because of a problem with humidity. It can be an indication that the lyo process for those containers has not worked properly. Last but not least, a cosmetic defect can occur so that the cake looks different and can cause customer complaints.

To detect the cake defect in the process two sets of product samples were needed, one good and the other bad. It was important that our customer gave us the exact properties of a cake defect type for the evaluation of the efficient classification of the model. A chemometric model was developed for the classification of defects. The model was validated using independent samples but the properties of these samples were known.   

The validation is based on the model properly predicting the characteristics / features of these known samples.

Our NIR inspection solution for 100% inline inspection of lyo cakes in vials

The engineering and method development studies resulted in an automated inspection platform that can 100% test multiple product sizes at speeds of up to 600 vials per minute. The cake defect detection can be measured non-destructively and at a high throughput.

Benefits of our NIR lyo inspection solution

  • Measurement results are available within seconds
  • Non-destructive inspection
  • Accurate and validated measurements
  • Environmentally friendly, no sample preparation or chemical waste
  • Safe, no chemical reaction
  • Versatile and simultaneous determination of various parameters
  • Easy to operate and user friendly
  • High-speed up to 600 vials per minute
  • There are cake defects which are not visible and can therefore not be detected by automated visual inspection