(W1130-12-79) Personalisation of Data Matrix Encoded Hydrocortisone Orodispersible Films Using Inkjet Printing

Purpose: The versatility and precision offered by inkjet printing allows the design of unique digital patterns on substrates, introducing novel dosage forms which may contain useful information easily readable by smartphones. In this study, the feasibility of inkjet printing was evaluated to develop flexible doses of data-enriched edible pharmaceuticals (DEEPs) loaded with hydrocortisone (HC), introducing the M3dimaker Studio™ data matrix-generator software specifically focused on the healthcare sector.

Methods: Data matrix code generation: The data matrix code-generator M3dimaker Studio™ software (FABRX Ltd., London, UK) was designed specifically for medical use (Figure 1). Once the application form was filled and the printing confirmed, a PDF document was generated with the scaled data matrix codes which encoded the information of interest. In addition, the number of printing layers necessary to obtain the target dose was indicated. For the size scalation of the data matrix, the software used parameters such as the printer resolution and the volume of ink that the printer deposits in each drop. Ink formulation: The formation of inclusion complexes with HC and β-cyclodextrins (β-CD) was tested to increase the poor drug solubility and the amount of deposited drug in each printed layer. β-cyclodextrins were added in different weight ratios for the formation of the inclusion complexes with the drug but HC:β-CD (ratio 1:3) was found to be optimal, with less material usage and an increased drug solubility. HC (300 mg) and the corresponding amount of β-CD (900 mg) were placed in a flask. 25 mL of propylene glycol:water (PG:H₂O) was added and incubated in a shaker at 100 rpm, at 37 °C for 24 h. Approximately 4 mg of E-122 red colorant was added to PG:H₂O (30:70 v/v), and blue colorant to PG:H₂O (60:40 v/v). The final solution was filtered through a 0.45 µm filter. Inkjet printing of hydrocortisone films: The printing tests were carried out using a thermal inkjet printer, HP Deskjet 3420 (Hewlett Packard, Palo Alto, USA). HP printer ink cartridges (black and tricolour, model numbers HP27 and HP28, respectively) were modified by cutting off the top, removing the sponges, and removing the commercial ink with distilled water, followed by ethanol. Once the cartridges were cleaned, they were loaded with the custom developed inks and placed inside the printer. Printing tests were performed on a substrate based on potato starch with a thickness of 0.33 mm.

Results: For data matrix printing, the software indicated the number of layers and adjusted the size to obtain a specific dose. These options, in combination with the accuracy of inkjet printing, obtains orodispersible films with a personalized dose and a data matrix code which can be read easily with a smartphone. The web software prototype can be complemented with a smartphone application that lets the printed code be captured by the device camera, accessing and consulting the information contained within (Figure 1). Data matrix codes with the same area were generated and printed using the different HC inks (Figure 2A). To highlight the possibility of carrying out a multiple printing approach, data matrix codes with different sizes were generated by the software (Figure 2B). During the printing process, films with up to 4 layers of ink were obtained using a data matrix pattern with the relevant encoded information. The amount of printed HC on data matrix codes was determined and the maximum printed dose was 47 µg with PG:H₂O (60:40 v/v) + HC ink (Figure 3). The highest amounts of HC were obtained with inks with the highest proportion of PG. Therefore, it can be observed that a higher proportion of organic solvent as well as the use of cyclodextrins caused an increase in the solubility of the HC within the ink, increasing the drug content deposited on the substrate. In the case of the 30:70 ratio ink, there were clear differences between the ink with and without cyclodextrins in terms of the amount of drug printed. However, there were no differences between the ink with and without cyclodextrins in the case of the 60:40 ratio ink. The HC deposited was slightly higher in the third layer with the ink containing cyclodextrins but decreased in the fourth layer. This can be attributed to the inconsistency of the deposition due to the modified desktop printer, which could be improved in the future.

Conclusion: Prototype web software specifically focused on healthcare sector was successfully implemented in combination with inkjet printing to prepare DEEPs containing a potent drug, hydrocortisone. The films were successfully printed using the simple printing option in the software and it was demonstrated that it is possible to print different sizes of data matrix code films by selecting the multiple printing option. Orodispersible films containing flexible and low doses of HC were successfully formulated, and the development of a code generator software oriented to medical use provides an additional advantage to personalised medicine safety and accessibility.