Figure 1.
Analysis of TE deposited pharmaceutical films on Ti-substrates.
a) Raman spectra of the deposited and reference acetyl salicylic acid (ASS), showing clear Raman peaks in the TE deposited ASS. 3D AFM image in the figure a, from the TE ASS sample, shows the micro-crystallites of ASS. b–e: The antimicrobial activity of Erythromycin (b: control, c: TE deposited) against Staphylococcus aureus and of Itraconazole (d: control, e: TE deposited) against Candida albicans demonstrated in agar diffusion tests. The activity is significantly increased in the case of specimen deposited by TE. f) Tuneable crystallinity: 3D Atomic force microscope image of Nipasol grown on Ti substrate at room temperature resulting in a much larger crystal size as compared to that deposited at −100°C as shown in g) which is nano-crystalline. h) & j) SEM images of nanostructured Cholesterol h) and Tetracaine-HCl j) drugs respectively fabricated on different substrates by thermal evaporation showing nanoscale spikes, see insets. The nanospike or platelet like geometries result from the growth kinetics.
Table 1.
Overview of thermally evaporated different drug substances.
Figure 2.
Representative optical microscopy and SEM images of various active pharmaceutical ingredients grown on different substrates synthesised by TE process (a–c) optical images of various Pilocarpine-HCl micro- or nanostrucured morphologies on different substrates like glass (a), polymer foil (b), Ti (c), d–f: SEM images of Ascorbic acid deposited on Si substrate at lower and higher magnifications; g–i: SEM images of Tetracaine-HCl nanostructures deposited on titanium substrate (g), silicon wafer coated with 20 nm Au thin film (h) and silicon coated with 4 nm Au thin film (i).
The inset images inside figures 2 g) to 2 h) show their magnified SEM view of deposited drug respectively.
Figure 3.
Lateral structuring of pharmaceutical substances.
a) Representative SEM images of microstructured ASS morphology by deposition through a microscopic shadow mask. b) magnified SEM image of the square shaped of the deposited drug. c): current voltage response of a pharmaceutical field effect transistor (PFET) of Pilocarpine-HCl, cross section scheme (upper left) and part of the waver (lower right) used for the lateral structuring of the Pilocarpine-HCl PFET fabrication are shown as insets.
Figure 4.
Multilayer and co-deposition experiments with pharmaceutical substances.
a) Comparative dissolution profile of Metronidazole alone and Metronidazole covered with the PLGA thin layer. The insets (i) and (ii) in the fig. 4a show the schematic of the multilayer coating and SEM image of the TE deposited Metronidazole drug respectively. b) 3D SEM micrograph an a cross section cut in the structure of a double layer showing top layer of Tetracaine and second layer of Metronidazole deposited on Ti substrate, c) SEM Image of the nanocomposite of Tetracaine-HCl with Ag on the Si substrate fabricated by co-deposition from two sources simultaneously sources and d) SEM image of Tetracaine-HCl without silver for comparison.