The future of pharmaceutical treatment and drug development is more and more based on the idea of personalised patient care. In this context orodispersible films (ODF) are gaining importance as an innovative drug delivery system. Namely, different dose sizes adapted to the pediatric population can be incorporated into ODF, while within geriatric populations who have difficulty in swallowing, ODF represent a quality alternative to tablets. In addition, better manageability of hospitalised patients who are likely to spit out the tablet afterwards can be achived.
Within the master's thesis the development and evaluation of ODF was based on nanocrystalline cellulose (NCC) from two different manufacturers, differing also in macroscopic characteristics (i.e. powder or gel NCC). Firstly the optimal composition of hydrogels from NCC, three different natural polymers (alginate, pectin or low viscosity chitosan), glycerol, and calcium ions, was developed. NCC is a natural polymer that does not exceed 100 nm in at least one dimension, while natural polymers increase crosslinking of the polymer chains and improve the mechanical properties of the hydrogel network. In the second part of the thesis, the influence of two different NCC and calcium ions on the viscosity and frequency dependence of the elastic and plastic modulus was evaluated by rheological measurements. Specifically, we wanted to ascertain whether rheological parameters affect the thickness and mechanical properties of ODF. The powderish NCC was found to form more viscous hydrogels and that the addition of calcium ions either increased or decreased the viscosity depending on the natural polymer used. Based on the frequency dependence of the elastic and plastic modulus of hydrogels with alginate and pectin, it was observed that the difference between the modules should be as large as possible for good mechanical properties of ODF. Also, the strength of the gel network was found to depend on the NCC concentration, the chemistry of the natural polymer used, and the addition of calcium ions. In the third part of the thesis, ODF’s disintegration time plus mechanical properties within tensile testing were evaluated. The highest tensile strength, despite unfavourable rheological values of the hydrogel, was achieved by ODF prepared from gelish NCC and low viscosity chitosan, the highest values of Young's modulus and maximum relative elongation were achieved by ODF with powderish NCC and alginate. The most suitable ODF based on tensile testing results were those with powderish NCC and alginate or pectin, as they had high tensile strength, high Young’s modulus and a maximum relative elongation greater than 10 %. Furthermore, by employing the disintegration time test in conjunction with the mechanical properties of ODF, it was found that ODF from pectin have the most suitable disintegration time and allow the easiest handling.
Based on all the results, ODF developed with pectin and alginate, regardless of the NCC type added, are considered as the most suitable for the further development of dosage form.
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