FTIR microscopy and confocal Raman microscopy for studying lateral drug diffusion from a semisolid formulation.
Fourier transform infrared (FTIR) microscopy was applied to obtain information on lateral drug diffusion of dithranol in artificial acceptor membranes. Lateral (2D) drug distribution into an artificial membrane was investigated on an area of 300microm x 1000microm with a lateral resolution of 25microm x 25microm by integrating a specific IR band located at 1430cm(-1). The concentration profiles show a heterogeneous distribution of dithranol particles resulting in non-uniform drug diffusion. Use of the FTIR microscope either in the transmission or in the reflection mode was restricted to a thickness of the DDC membrane <15microm. The third dimension (depth profile) was analysed by means of confocal Raman microscopy (CRM). In an artificial membrane, the depth range from a minimum of 1.5microm up to a maximum of 49microm was analysed for dithranol distribution.
Gotter
B
B
Institute of Pharmacy, Martin Luther University, Halle/Saale, Germany. bernhard.gotter@pharmazie.uni-halle.de
Faubel
W
W
Neubert
R H H
RH
D000875:Anthralin / Q000032:analysis / Q000737:chemistry; D003101:Collodion; D004058:Diffusion; D007851:Dodecanol / Q000737:chemistry; D016503:Drug Delivery Systems / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods; D008567:Membranes, Artificial; D008853:Microscopy / Q000295:instrumentation / Q000379:methods*; D018613:Microscopy, Confocal / Q000295:instrumentation / Q000379:methods*; D009824:Ointments / Q000737:chemistry; D010232:Paraffin / Q000737:chemistry; D004364:Pharmaceutical Preparations / Q000032:analysis / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*; D013059:Spectrum Analysis, Raman / Q000379:methods; D013997:Time Factors
D008567:Membranes, Artificial; D009824:Ointments; D004364:Pharmaceutical Preparations; D007851:Dodecanol; D010232:Paraffin; D003101:Collodion; D000875:Anthralin