Guar gum-pullulan films produced by semisolid extrusion 3D printing for sublingual nifedipine administration

The sublingual route offers an efficient alternative for drug administration, improving patient comfort and drug bioavailability. Films are an interesting pharmaceutical solid dosage form for application to the sublingual mucosa. Nifedipine is an anti-hypertensive drug; however, it presents low oral bioavailability and short half-life, being a candidate for sublingual administration. Thus, films containing nifedipine (GGP-NIFE-HG-F) were developed. The printing inks were prepared with a blend of guar gum (4%) and pullulan (4%) using dimethyl sulfoxide (DMSO) to solubilize nifedipine. The polysaccharide blend exhibited a rheological profile suitable for producing films using the semisolid extrusion (SSE) technique. The films were successfully obtained, with nifedipine content close to theoretical values (95.26 ± 3.55%), and demonstrated the possibility of customizing drug doses. Mechanical evaluation indicated that DMSO improved flexibility, acting as a plasticizer. All films exhibited rapid dispersion (>30 s) and disintegration (>3 min), consistent with their high swelling index (<700%). The hemolysis and HET-CAM assays suggest that films are safe for human use, and texture analysis showed that GGP-NIFE-HG-F has adhesion to sublingual mucosa (919.7 ± 159.3 mN/mm), classified as mucoadhesive. The in vitro release test confirmed that guar gum effectively controlled nifedipine release. Despite this controlled release, the polymeric vehicle did not obstruct/hinder the passage of nifedipine through the sublingual mucosa, indicating that the drug can reach the bloodstream. These findings indicate that films designed for sublingual administration could serve as a promising new method for delivering nifedipine.