Biomedical subjects

Lucinda F Buhse

Publications and source records attributed to Lucinda F Buhse.

3 recordsLinked to original sources

PubMed2006

Transdermal drug delivery system (TDDS) adhesion as a critical safety, efficacy and quality attribute.

Transdermal drug delivery systems (TDDS), also known as "patches," are dosage forms designed to deliver a therapeutically effective amount of drug across a patient's skin. The adhesive of the transdermal drug delivery system is critical to the safety, efficacy and quality of the product. In the Drug Quality Reporting System (DQRS), the United States Food and Drug Administration (FDA) has received numerous reports of "adhesion lacking" for transdermal drug delivery systems. This article provides an overview of types of transdermals, their anatomy, the role of adhesion, the possible adhesion failure modes and how adhesion can be measured. Excerpts from FDA reports on the lack of adhesion of transdermal system products are presented. Pros and cons of in vitro techniques, such as peel adhesion, tack and shear strength, in vivo techniques used to evaluate adhesive properties are discussed. To see a decrease in "adhesion lacking" reports, adhesion needs to become an important design parameter and suitable methods need to be available to assess quality and in vivo performance. This article provides a framework for further discussion and scientific work to improve transdermal adhesive performance.

Administration, Cutaneous↗

PubMed2006

Effects of deaeration methods on dissolution testing in aqueous media: a study using a total dissolved gas pressure meter.

Dissolution testing is a critical method for the determination of pharmaceutical product quality and bioequivalence. For some products, dissolved gases in the dissolution medium affect dissolution results thus requiring degassing of the medium prior to use. In this study, we use a total dissolved gas and oxygen meter to measure both oxygen and total gases in dissolution media before and after application of a variety of deaeration methods. Dissolution testing results using a 10 mg Prednisone tablet (NCDA #2) are compared with the percent saturation of oxygen and total gases found in the medium. Reaeration of the medium during different stirring rates was also measured. This study confirms that measurement of total gases and not just oxygen in the medium is necessary to assess adequacy for dissolution testing. For those deaeration techniques that are performed at room temperature, the percent saturation of the total dissolved gases must be well below 100% to prevent outgassing once medium is brought to dissolution test method temperature, typically 37 degrees C.

Chemistry, Pharmaceutical↗

PubMed2005

Quality assessment of internet pharmaceutical products using traditional and non-traditional analytical techniques.

This work investigated the use of non-traditional analytical methods to evaluate the quality of a variety of pharmaceutical products purchased via internet sites from foreign sources and compared the results with those obtained from conventional quality assurance methods. Traditional analytical techniques employing HPLC for potency, content uniformity, chromatographic purity and drug release profiles were used to evaluate the quality of five selected drug products (fluoxetine hydrochloride, levothyroxine sodium, metformin hydrochloride, phenytoin sodium, and warfarin sodium). Non-traditional techniques, such as near infrared spectroscopy (NIR), NIR imaging and thermogravimetric analysis (TGA), were employed to verify the results and investigate their potential as alternative testing methods. Two of 20 samples failed USP monographs for quality attributes. The additional analytical methods found 11 of 20 samples had different formulations when compared to the U.S. product. Seven of the 20 samples arrived in questionable containers, and 19 of 20 had incomplete labeling. Only 1 of the 20 samples had final packaging similar to the U.S. products. The non-traditional techniques complemented the traditional techniques used and highlighted additional quality issues for the products tested. For example, these methods detected suspect manufacturing issues (such as blending), which were not evident from traditional testing alone.

Chromatography, High Pressure Liquid↗