Hyperspectral imaging in quality control of inkjet printed personalised dosage forms

The aim of the study was to investigate applicability of near infra-red (NIR) hyperspectral imaging technique in quality control of printed personalised dosage forms. Inkjet printing technology was utilized to fabricate escalating doses of an active pharmaceutical ingredient (API). A solution containing anhydrous theophylline as the model drug was developed as a printable formulation. Single units solid dosage forms (SDFs) were prepared by jetting the solution onto 1 cm × 1 cm areas on carrier substrate with multiple printing passes. It was found that the number of printing passes was in excellent correlation (R2 = 0.9994) with the amount of the dispensed drug (μg cm−2) based on the UV calibration plot. The API dose escalation was approximately 7.5 μg cm−2 for each printing pass concluding that inkjet printing technology can optimally provide solutions to accurate deposition of active substances with a potential for personalized dosing. Principal component analysis (PCA) was carried out in order to visualize the trends in the hyperspectral data. Subsequently, a quantitative partial least squares (PLS) regression model was created. NIR hyperspectral imaging proved (R2 = 0.9767) to be a reliable, rapid and non-destructive method to optimize quality control of these planar printed dosage forms.