New concepts for transdermal delivery of oxygen based on catalase biochemical reactions studied by oxygen electrode amperometry

Abstract

11A bio-inspired coating consisting of pectin (polygalacturonic acid) and cationic cellulose nano-12 fibers were successfully produced by the Layer-by-layer method. The build-up and the morphol-13 ogy of the resulting coatings were studied with spectroscopic ellipsometry and atomic force mi-14 croscopy, respectively. The coating was able to survive the exposure of a simulated gastric fluid, 15 but was partially degraded upon exposure to pectinase enzyme, which simulate the action of the 16 microbial symbionts present in the human colon. Prior to exposure, the oxygen permeability co-17 efficient of the coating (0.033 ml (STP) mm m -2 day -1 atm -1 at 23°C and 20% RH) was in the 18 same order of magnitude as for ethylene vinyl alcohol films (0.001-0.01 ml (STP) mm m -2 day -19 1 atm -1 ). However after exposure to the mimicked gastrointestinal (GI) tract conditions, the con-20 tribution of coating to the overall barrier properties was not measurable. 21 22

Platelet-Rich Fibrin Can Neutralize Hydrogen Peroxide-Induced Cell Death in Gingival Fibroblasts

“…Even though it remains unclear whether platelets are the exclusive source of catalase, these findings provide new perspectives to understand how PRF exerts its beneficial effects in vivo [5]. High amounts of native catalase are present in the healthy skin organ [32] but not in situations where wound healing is impaired by the lack of catalase including skin diseases, such as vitiligo [33], psoriasis [34], and presumably also in refractory leg ulcers [6]. PRF and its respective membrane, and particular the buffy coat layer including parts of the erythrocyte fraction could become a rich source of catalase to support wound healing and may replace or complement traditional clinical strategies where catalase and mimetics are applied for the treatment of skin diseases and wound injury [33,35].…”

The Potential of Caffeic Acid Lipid Nanoparticulate Systems for Skin Application: In Vitro Assays to Assess Delivery and Antioxidant Effect

“…Noteworthily, in order to compare the in vivo antioxidant potential of CA encapsulated in SLN and in ETHO, an amperometry-based approach has been employed. This recently developed electrochemical technique, based on the use of a pig skin covered oxygen electrode (SCOE), allows predicting the kinetics of antioxidant molecules penetration across the stratum corneum and its further engagement in anti-oxidative reactions, occurring in the skin in the presence of hydrogen peroxide (H 2 O 2 ) [33,34]. The SCOE method enables measuring the alterations in O 2 concentration within the skin due to the reactions of H 2 O 2 with antioxidants, mimicking in this way their cutaneous administration [33].…”

“…This recently developed electrochemical technique, based on the use of a pig skin covered oxygen electrode (SCOE), allows predicting the kinetics of antioxidant molecules penetration across the stratum corneum and its further engagement in anti-oxidative reactions, occurring in the skin in the presence of hydrogen peroxide (H 2 O 2 ) [33,34]. The SCOE method enables measuring the alterations in O 2 concentration within the skin due to the reactions of H 2 O 2 with antioxidants, mimicking in this way their cutaneous administration [33]. In this study, the SCOE approach was employed to compare the penetration enhancer properties of SLN and ETHO upon cutaneous application, as well as the antioxidant power exerted by CA encapsulated in the two nanosystems.…”

Visualisation of H2O2 penetration through skin indicates importance to develop pathway-specific epidermal sensing

“…This work exploits an in vitro Franz cell set-up that demonstrates that initial developments of epidermal sensing can be achieved without using animal models. The results obtained in this work are also relevant to improve methods of topical application of H 2 O 2 containing formulations for tissue oxygenation, which is one of the means to stimulate angiogenesis and healing of chronic wounds [25,26].…”

“…The inhibition process was confirmed by using skin membranes firmly attached to oxygen electrodes. The set-up is known as skin-covered oxygen electrode (SCOE), which measures O 2 liberated by skin catalase when the electrode is exposed to a solution of H 2 O 2 [25,28,37]. Figure S1 in the supporting information provides an example of the current response when the SCOE is exposed to H 2 O 2 in the absence and in the presence of a catalase inhibitor, specifically sodium azide, NaN 3 .…”