RT journal article
T1 Toward In Vivo Transdermal pH Sensing with a Validated Microneedle Membrane Electrode
A1 García Guzmán, Juan José
A1 Pérez Ràfols, Clara
A1 Cuartero, María
A1 Crespo, Gastón A.
A2 Química Analítica
K1 Ion-selective electrodes
K1 pH sensing
K1 in vivo monitoring
K1 microneedle transdermal sensing
K1 validation
AB We present herein the most complete characterization ofmicroneedle (MN) potentiometric sensors for pH transdermal measurementsfor the time being. Initial in vitro assessment demonstrated suitable analyticalperformances (e.g., Nernstian slope, linear range of response from 8.5 to 5.0, andfast response time) in both buffer media and artificial interstitial fluid (ISF).Excellent repeatability and reproducibility together with adequate selectivity andresiliency facilitate the appropriateness of the new pH MN sensor for transdermalISF analysis in healthcare. The ability to resist skin insertions was evaluated inseveral ex vivo setups using three different animal skins (i.e., chicken, pork, andrat). The developed pH MN sensor was able to withstand from 5 to 10 repetitiveinsertions in all the skins considered with a minimal change in the calibrationgraph (<3% variation in both slope and intercept after the insertions). Ex vivo pHmeasurements were validated by determining the pH with the MN sensor and acommercial pH electrode in chicken skin portions previously conditioned atseveral pH values, obtaining excellent results with an accuracy of <1% and a precision of <2% in all cases. Finally, pH MN sensorswere applied for the very first time to transdermal measurements in rats together with two innovative validation procedures: (i)measuring subcutaneous pH directly with a commercial pH microelectrode and (ii) collecting ISF using hollow MNs and then thepH measurement of the sample with the pH microelectrode. The pH values obtained with pH MN sensors were statistically moresimilar to subcutaneous measurements, as inferred by a paired sample t-test at 95% of confidence level. Conveniently, the validationapproaches could be translated to other analytes that are transdermally measured with MN sensors.
PB ACS
SN 2379-3694
YR 2021
FD 2021
LK http://hdl.handle.net/10498/36661
UL http://hdl.handle.net/10498/36661
LA eng
NO Stiftelsen Olle Engkvist Byggmästare (Project Grant 204-0214), and the Novo Nordisk Fonden (Exploratory Pre-Seed Grant 19OC0056171)
DS Repositorio Institucional de la Universidad de Cádiz
RD 09-nov-2026