1. 3 Drug Delivery Systems, St. Paul, MN, USA 55144
Transparent UV Protective Backings containing Nanosized Titanium Dioxide for Transdermal Drug Delivery Applications
Chad R. Wold
3 Drug Delivery Systems, St. Paul, MN, USA
Introduction
Results
Results, Cont.
Various active drugs used in transdermal drug delivery systems are widely known to exhibit photochemical degradation upon light exposure. During storage, these products are well protected from light by the packaging foil. However, during wear, exposure to sunlight may result in undesired degradation of the active drug.
Historically, transdermal drug delivery systems with ultraviolet (UV) sensitive components often utilized an opaque backing material to reduce photo-degradation. These backings, which are usually pigmented or contain a metallic foil layer, are limited by their aesthetic appearance. The purpose of this work was to develop a backing film that provides UV protection by utilizing nanosized TiO2 while maintaining transparency of the backing film.
Depending on the type and content of the UV protective components, a systematic reduction in drug degradation was observed. The addition of 0.5 % w/w of nanosized TiO2 in the transdermal backing substantially decreased the amount of drug degradation versus the control study that was not irradiated by UV-Visible exposure.
Fig 2 – UV Absorbance ability of TiO2 as a function of concentration in backing film.
Fig 4 – Pros and Cons of Inorganic versus Organic Absorbers.
Fig 1 – UV Absorbance range of several inorganic and organic materials suitable for dermal applications.
Fig 3 – Effect of TiO2 concentration on the loss of drug content upon UV exposure at ICH conditions.
Methods
Conclusions
Novel transparent olefin backings with exceptional UV protective properties were developed in this study. The backings were developed by first compounding nanosized TiO2 into the polymer matrix. These compounded polymers were then extruded as thin films for analysis. The resulting thin films were then used as the backing component in a drug-in-adhesive patch construction containing two UV-sensitive labile drugs. The transdermal patches were then tested by irradiating the patches under ICH guidelines of not less than 1.2 million lux hours of visible exposure and not less than 200 watt hours/m2 of UV exposure.
The addition of nanosized TiO2 into the transdermal backing substantially enhanced the UV-protective properties while maintaining transparency. The results demonstrate that incorporation of nanosized TiO2 into the transdermal backing significantly decreased photochemical degradation of the active drug.
3 Drug Delivery Systems