Abstract
Ex-vivo and in-vivo skin analysis has been extensively evaluated by confocal Raman spectroscopy (CRS). The off-line measurement with a CRS-suited skin-mounted device after Franz-cell incubations is the most popular choice. However, real-time monitoring of in-line measurement has clear advantages for obtaining dynamic and more timely results. In our study, a custom-built setup suitable for in-line measurements was implemented, which ensures constant skin incubation and in-situ skin detections. We aim to compare the differences between using in-line and off-line devices for monitoring skin drug penetrations. A well-assessed formulation gel with procaine-HCl as the active ingredient was used as reference. The PEG-23 lauryl ether was added to the formulation as a penetration enhancer to evaluate the enhancement effects of procaine on skin. After incubation times of 14, 20, and 24 h, skin penetration profiles were assessed. Comparable results between off-line and in-line measurements were obtained. Remarkable improvements in penetrated procaine amount and depth were observed. Based on the significant differences of their enhanced penetration amounts, fairly similar estimations were achieved from both methods. A slight difference of 14 h incubation between these two setups can still be found, which may be due to the different detection conditions and affected skin properties. Overall, in-line measurements could provide a more time- and labor-saving alternative for off-line measurements in ex-vivo study.
Highlights
The skin is the largest organ of the human body and is considered as a crucial route for drug deliveries [1,2,3]
We compared the results on the skin penetration of procaine-HCl obtained by two different methods, in-line and off-line measurements
Our results show that both methods demonstrate the expected and already described influences of L23 as a penetration enhancer for procaine-HCl embedded formulations
Summary
The skin is the largest organ of the human body and is considered as a crucial route for drug deliveries [1,2,3]. With the topical application of components, non-invasive and efficient techniques for monitoring their skin penetrations are strongly needed. Confocal Raman spectroscopy (CRS) as a method for skin penetration studies in-vivo and ex-vivo is on the rise [4,5,6,7]. Different methods have been described for obtaining depth profiles of topically applied actives using CRS [8,9]. In skin in-vivo studies, in-line measurements have been widely described for monitoring the distribution of actives or excipients on human skin [10,11]. The use of human skin faces a lot of difficulties concerning accessibility due to ethnic problems and poor convenience
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
