Properties Of Skin Research Articles

Numerical analysis on the fate and transport of TiO2 nanoparticles in fractured porous media: Addressing intrinsic heterogeneities in sorptive mass transfer

The aggregation and slow migration of nanoparticles in aqueous media have caused serious concerns about their fate and impacts in the subsurface environment. Anthropogenic release and distribution of TiO2 nanoparticles (TNP) have immense potential for surface adsorption, occlusion, impregnation, bioaccumulation, and phase partition into various environmental compartments, and the actual risks in their interactions are still unknown. In an attempt to realize the extent of source zone migration of TNP in a fracture-skin-matrix (F-S-M) medium, a numerical model is developed and analyzed for sensitivity of certain features of the flow field. In addition, the sorptive mass transfer is simulated under four characteristic scenarios with varying assumptions pertaining to the intrinsic heterogeneities. The simulation results highlight the non-selective regulatory role of the skin in providing temporary interfacial space for reversible adsorption between the fracture and the matrix as well as in retarding the desorption rate. A preferential detachment of TNP is observed to be favored by the enhanced properties of skin due to the similarity in diffusion and dispersion coefficients. Out of the four scenarios, the two-site model and two-step model simulated the dynamic pore-filling features of adsorption pertaining to the heterogeneities in TNP and F-S-M characteristics. The results demonstrate that the proposed numerical could fairly detect the transition between local equilibrium and dynamic adsorption-desorption cycles that would eventually determine the mass transfer limitations and the extent of elution of TNP along the flow.

Changes in Texture and Collagen Properties of Pork Skin during Salt-Enzyme-Alkali Tenderization Treatment.

The effects of salt-enzyme-alkali progressive tenderization treatments on porcine cortical conformation and collagen properties were investigated, and their effectiveness and mechanisms were analyzed. The tenderization treatment comprised three treatment stages: CaCl2 (25 °C/0-30 min), papain (35 °C/30-78 min), and Na2CO3 (25 °C/78-120 min). The textural, microscopic, and collagenous properties (content, solubility, and structure) of pork skin were determined at the 0th, 30th, 60th, 90th, and 120th min of the treatment process. The results showed that the shear force, hardness, and chewability of the skin decreased significantly (p < 0.05), and the elasticity exhibited a gradual increase with the progression of tenderization. The content and solubility of collagen showed no significant change at the CaCl2 treatment stage. However, the soluble collagen content increased, the insoluble collagen content decreased, and the collagen solubility increased by 18.04% during the subsequent treatment with papain and Na2CO3. Meanwhile, the scanning electron microscopy results revealed that the regular, wavy structure of the pig skin collagen fibers gradually disappeared during the CaCl2 treatment stage, the overall structure revealed expansion, and the surface microscopic pores gradually increased during the papain and Na2CO3 treatment stages. The findings of the Fourier transform infrared spectroscopy analysis indicated that the hydrogen bonding interactions between the collagen molecules and the C=O, N-H and C-N bonds in the subunit structure of collagen were substantially altered during treatment and that the breakage of amino acid chains and reduction in structural ordering became more pronounced with prolonged treatment. In the tertiary structure, the maximum emission wavelength was blue-shifted and then red-shifted, and the fluorescence intensity was gradually weakened. The surface hydrophobicity was slowly increased. The salt-enzyme-alkali tenderization treatment considerably improved the physical properties and texture of edible pork skins by dissolving collagen fibers and destroying the structure of collagen and its interaction force.

VP-net: an end-to-end deep learning network for elastic wave velocity prediction in human skin in vivo using optical coherence elastography.

Acne vulgaris, one of the most common skin conditions, affects up to 85% of late adolescents, currently no universally accepted assessment system. The biomechanical properties of skin provide valuable information for the assessment and management of skin conditions. Wave-based optical coherence elastography (OCE) quantitatively assesses these properties of tissues by analyzing induced elastic wave velocities. However, velocity estimation methods require significant expertise and lengthy image processing times, limiting the clinical translation of OCE technology. Recent advances in machine learning offer promising solutions to simplify velocity estimation process. In this study, we proposed a novel end-to-end deep-learning model, named velocity prediction network (VP-Net), aiming to accurately predict elastic wave velocity from raw OCE data of in vivo healthy and abnormal human skin. A total of 16,424 raw phase slices from 1% to 5% agar-based tissue-mimicking phantoms, 28,270 slices from in vivo human skin sites including the palm, forearm, back of the hand from 16 participants, and 580 slices of facial closed comedones were acquired to train, validate, and test VP-Net. VP-Net demonstrated highly accurate velocity prediction performance compared to other deep-learning-based methods, as evidenced by small evaluation metrics. Furthermore, VP-Net exhibited low model complexity and parameter requirements, enabling end-to-end velocity prediction from a single raw phase slice in 1.32ms, enhancing processing speed by a factor of ∼100 compared to a conventional wave velocity estimation method. Additionally, we employed gradient-weighted class activation maps to showcase VP-Net's proficiency in discerning wave propagation patterns from raw phase slices. VP-Net predicted wave velocities that were consistent with the ground truth velocities in agar phantom, two age groups (20s and 30s) of multiple human skin sites and closed comedones datasets. This study indicates that VP-Net could rapidly and accurately predict elastic wave velocities related to biomechanical properties of in vivo healthy and abnormal skin, offering potential clinical applications in characterizing skin aging, as well as assessing and managing the treatment of acne vulgaris.

Multiplexed Piezoelectric Electronic Skin with Haptic Feedback for Upper Limb Prosthesis

AbstractUpper limb amputation severely impairs tactile perception, limiting daily activities. Developing a near‐natural replacement with prosthetic devices requires improving user sensory experiences during object interactions. The ideal upper limb prosthesis should provide real‐time sensory feedback, mirroring natural experiences. Current prostheses struggle with providing adequate tactile feedback due to sensory limitations. Inspired by the sensory properties of skin, we present a micro‐fabricated, multiplexed electronic skin (e‐skin) with actuators for sensory feedback in upper limb amputation. The piezoelectric‐capacitive sensor array detects static pressure, temperature, vibration, and texture, with integrated actuators stimulating the skin to provide real‐time feedback. The sensors integrate with actuators via readout electronics, making the system standalone and easy to use. The flexible, compact sensor array design (two pixels within a 1 cm² footprint) detects a wide range of pressure (0.5–10 kPa), temperature (22–60 °C), vibration (35–100 Hz), and texture (2.5–45 Hz), suitable for daily use. The e‐skin, attached to a prosthetic finger, is tested for feasibility on human volunteers with wrist‐mounted actuators. Statistics are used to quantitatively assess system performance. The integration of multiplexed sensors and actuators enhances tactile feedback, improving the quality of life for people with upper limb amputations.

Dietary lipid is largely deposited in skin and rapidly affects insulating properties.

Skin has been shown to be a regulatory hub for energy expenditure and metabolism: mutations of skin lipid metabolism enzymes can change the rate of thermogenesis and susceptibility to diet-induced obesity. However, little is known about the physiological basis for this function. Here we show that the thermal properties of skin are highly reactive to diet: within three days, a high fat diet reduces heat transfer through skin. In contrast, a dietary manipulation that prevents obesity accelerates energy loss through skins. We found that skin was the largest target in a mouse body for dietary fat delivery, and that dietary triglyceride was assimilated both by epidermis and by dermal white adipose tissue. Skin from mice calorie-restricted for 3 weeks did not take up circulating lipids and showed a highly depleted stratum corneum. Dietary triglyceride acyl groups persist in skin for weeks after feeding. Using multi-modal lipid profiling, we have implicated both keratinocytes and sebocytes in the altered lipids which correlate with thermal function. In response to high fat feeding, wax diesters and ceramides accumulate, and triglycerides become more saturated. In contrast, in response to the dramatic loss of adipose tissue that accompanies restriction of the branched chain amino acid isoleucine, skin becomes more heat-permeable, resisting changes induced by Western diet feeding, with a signature of depleted signaling lipids. We propose that skin should be routinely included in physiological studies of lipid metabolism, given the size of the skin lipid reservoir and its adaptable functionality.

State-of-the-Art in Skin Fluorescent Photography for Cosmetic and Skincare Research: From Molecular Spectra to AI Image Analysis.

Autofluorescence is a remarkable property of human skin. It can be excited by UV and observed in the dark using special detection systems. The method of fluorescence photography (FP) is an effective non-invasive tool for skin assessment. It involves image capturing by a camera the emission of light quanta from fluorophore molecules in the skin. It serves as a useful tool for cosmetic and skincare research, especially for the detection of pathological skin states, like acne, psoriasis, etc. To the best of our knowledge, there is currently no comprehensive review that fully describes the application and physical principles of FP over the past five years. The current review covers various aspects of the skin FP method from its biophysical basis and the main fluorescent molecules of the skin to its potential applications and the principles of FP recording and analysis. We pay particular attention to recently reported works on the automatic analysis of FP based on artificial intelligence (AI). Thus, we argue that FP is a rapidly evolving technology with a wide range of potential applications. We propose potential directions of the development of this method, including new AI algorithms for the analysis and expanding the range of applications.

Design of super stretchability, rapid self-healing, and self-adhesion hydrogel based on starch for wearable strain sensors

Since hydrogels are conductive, easily engineered, and sufficiently flexible to imitate the mechanical properties of human skin, they are seen as potential options for wearable strain sensors. However, it is still a great challenge to prepare a hydrogel through simple and straightforward methods that integrate excellent stretchability, ionic conductivity, toughness, self-adhesion, and self-healing. Herein, an acrylamide/3-acrylamide phenylboronic acid cross-linked network is modified to produce a semi-interpenetrating cross-linked hydrogel in just one easy step by adding starch. The prepared hydrogel contains dynamic boronic ester bonds and hydrogen bonds, which endow the exceptional stretchability (5769–13,976 %, 20–50 wt%), ideal transmittance (>90 %), self-adhesiveness (0.636 ± 0.060 kPa, 30 wt%), and self-healing properties. Notably, the self-healing process is completed instantly, achieving a healing strength of up to 81.21 %. Additionally, the aforementioned hydrogel exhibits a broad working strain range (≈ 500 %) and high sensitivity (gauge factor = 1.99) as a strain sensor, allowing it to record and track human actions precisely. This work provides a novel approach to synthesizing hydrogels with optimal overall mechanical characteristics, with the potential to facilitate the development of wearable strain sensing system based on hydrogels for real-world applications.

Lipid-Based Formulation of Baricitinib for the Topical Treatment of Psoriasis

Background: Baricitinib, commonly used for autoimmune diseases, is typically administered orally, which can lead to systemic adverse effects. A topical formulation could potentially offer localized therapeutic effects while minimizing these side effects. Objectives: This study focuses on developing a lipid-based topical formulation of baricitinib (BCT-OS) for treating psoriasis. Methods: The optimized formulation was then assessed for physical, chemical, and biopharmaceutical characterization. Furthermore, the anti-inflammatory efficacy of the formulation was tested in a model of psoriasis induced by imiquimod in mice, and its tolerance was determined by the evaluation of biomechanical skin properties and an inflammation test model induced by xylol in mice. Results: BCT-OS presented appropriate characteristics for skin administration in terms of pH, rheology, extensibility, and stability. The formulation also demonstrated a notable reduction in skin inflammation in the mouse model, and high tolerability without affecting the skin integrity. Conclusions: BCT-OS shows promise as an alternative treatment for psoriasis, offering localized therapeutic benefits with a potentially improved safety profile compared to systemic administration.

Pre-Holocene Taymyr Mammoth Petya: Mineralogical, Isotope, and Geochemical Properties of Bones, Soft Tissues, Skin, and Hair and Paleoecological Reconstructions

Pre-Holocene Taymyr Mammoth Petya: Mineralogical, Isotope, and Geochemical Properties of Bones, Soft Tissues, Skin, and Hair and Paleoecological Reconstructions

Polyphenol-Rich Cranberry Beverage Positively Affected Skin Health, Skin Lipids, Skin Microbiome, Inflammation, and Oxidative Stress in Women in a Randomized Controlled Trial.

This study aimed to determine whether a polyphenol-rich cranberry beverage affects skin properties, lipids, and the microbiome in women using a randomized, double-blinded, placebo-controlled, cross-over design. Twenty-two women with Fitzpatrick skin types 2-3 were randomized to drink a cranberry beverage or placebo for six weeks. After a 21-day washout, they consumed the opposite beverage for six weeks. Six weeks of cranberry beverage significantly reduced UVB-induced erythema, improved net elasticity on the face and forearm, smoothness on the face, and gross elasticity on the forearm compared to the placebo. When stratified by age, these effects of the cranberry beverage were primarily observed in women >40 years old. SOD activities were improved after six weeks of cranberry beverage consumption compared to the placebo, while glutathione peroxide and TNF-α were improved compared to baseline. These effects were found to differ by age group. Skin lipid composition was modulated by both the cranberry beverage and the placebo. Cranberry beverages did not change α- or β-diversity but altered the abundance of several skin microbes at the species and strain level. Consumption of a cranberry beverage for six weeks improved specific skin properties and oxidative stress and modulated skin lipids and microbiome compared to placebo.

Novel biophysical skin biomarkers discriminate topical anti‐inflammatory treatments based on their potential for local adverse effects

AbstractBackgroundTopical corticosteroids (TCS) are efficacious treatments for inflammatory skin conditions, however, there is a risk of adverse effects; understanding how best to use these treatments is an unmet research priority shared by patients and healthcare professionals.ObjectivesTo develop non‐invasive biomarkers of local adverse effects to facilitate the optimisation of topical therapy.MethodsAn observer‐blind randomised within‐subject controlled trial in atopic dermatitis patients was undertaken (NCT04194814) comparing betamethasone valerate 0.1% cream (BMV) to a non‐steroidal anti‐inflammatory treatment, crisaborole 2% ointment (CRB). Participants underwent 4 weeks twice‐daily treatment with CRB on one forearm and BMV on the other (left/right randomised). Skin properties were assessed on days 1, 15, 29 of treatment and again on day 57, including imaging of skin microstructure using Optical Coherence Tomography (OCT) and Attenuated Total Reflectance (ATR)‐Fourier Transform Infrared (FTIR) spectroscopic assessment of stratum corneum molecular structure. The primary outcome was the difference in the change in epidermal thickness from days 1 to 29.ResultsThirty‐seven participants received the first dose, of which 32 completed the study (all 37 were included in the analysis). Pathologic epidermal thinning at day 29 was significantly greater (p &lt; 0.0001) at sites treated with BMV (−31.66; 95% confidence interval: −35.31, −28.01 µm) compared to CRB (−13.76; −17.42, −10.10 µm). From a panel of exploratory biomarkers, superficial plexus depth and stratum corneum carboxyl group levels had the greatest ability to discriminate the effects of the TCS treatment (p &lt; 0.0001).ConclusionsBMV induced 2.3x more pathologic epidermal thinning than CRB after 4 weeks of treatment, suggesting that CRB may be more appropriate for longer‐term, proactive‐based, treatment strategies where the risks of adverse effects are greatest. By monitoring treatment effects using OCT and ATR‐FTIR spectroscopy, two new non‐invasive biomarkers of skin health have been identified with the potential to help optimise future safe treatment strategies.

Integrated analysis of facial microbiome and skin physio-optical properties unveils cutotype-dependent aging effects

BackgroundOur facial skin hosts millions of microorganisms, primarily bacteria, crucial for skin health by maintaining the physical barrier, modulating immune response, and metabolizing bioactive materials. Aging significantly influences the composition and function of the facial microbiome, impacting skin immunity, hydration, and inflammation, highlighting potential avenues for interventions targeting aging-related facial microbes amidst changes in skin physiological properties.ResultsWe conducted a multi-center and deep sequencing survey to investigate the intricate interplay of aging, skin physio-optical conditions, and facial microbiome. Leveraging a newly-generated dataset of 2737 species-level metagenome-assembled genomes (MAGs), our integrative analysis highlighted aging as the primary driver, influencing both facial microbiome composition and key skin characteristics, including moisture, sebum production, gloss, pH, elasticity, and sensitivity. Further mediation analysis revealed that skin characteristics significantly impacted the microbiome, mostly as a mediator of aging. Utilizing this dataset, we uncovered two consistent cutotypes across sampling cities and identified aging-related microbial MAGs. Additionally, a Facial Aging Index (FAI) was formulated based on the microbiome, uncovering the cutotype-dependent effects of unhealthy lifestyles on skin aging. Finally, we distinguished aging related microbial pathways influenced by lifestyles with cutotype-dependent effect.ConclusionsTogether, our findings emphasize aging’s central role in facial microbiome dynamics, and support personalized skin microbiome interventions by targeting lifestyle, skin properties, and aging-related microbial factors.8-x6JkQezK-S195ofXGtyGVideo

Translational potential of test systems in modelling thermal burn wounds

The article describes the advantages and features of experimental models of thermal burns using in vitro, ex vivo and in vivo test systems. An objective assessment of the application of each approach depending on the type of study is given. For example, cell culture models are simple but do not fully reflect the structure of human skin, which limits their translational value. Ex vivo models, such as skin explants, provide the necessary architectonics to study intercellular interactions, but they also have drawbacks, primarily related to short viability. In general, in vitro and ex vivo models have limitations in reproducing all aspects of burn wound pathogenesis and healing. In this regard, laboratory animals, primarily mice, rats, and pigs, are widely used to study burn wound pathology, its effects on the body, and the efficacy of therapy. The decision to use experimental animal models is made taking into account their translational relevance to humans. In rodents, wound healing occurs mainly by contraction, in contrast to the re-epithelialisation and granulation seen in humans, which contributes to faster wound healing in rodents. The significant similarities between certain properties of pig and human skin make the latter a relevant test system in pharmacodynamic studies of thermal burn wounds.

Design and validation of a DMA-inspired device for in-vivo measurement of human skin mechanics: a finite element analysis approach

Abstract This study introduces a novel method for measuring the mechanical properties of human skin in-vivo, inspired by dynamic mechanical analysis (DMA). We designed and applied a DMA-like device to living human skin and validated its functionality through finite element analysis (FEA) on an ideally elastic skin model. The device features multiple testing modes, including horizontal movement in both same and opposite directions with optional pre-stretching. Stress-strain behaviours obtained from FEA align with initial setup parameters, serving as powerful tools for further research into the mechanical properties of skin. This method is expected to have potential significance in biomechanical theory, clinical, and healthcare applications.

52651 Mapping skin properties in psoriasis for improved understanding of topical absorption

52651 Mapping skin properties in psoriasis for improved understanding of topical absorption

Design and Validation of a Monte Carlo Method for the Implementation of Noninvasive Wearable Devices for HbA1c Estimation Considering the Skin Effect.

To diagnose diabetes early or to maintain stable blood glucose levels in diabetics, blood glucose levels should be frequently checked. However, the only way to check blood glucose levels regularly is to use invasive methods, such as pricking the fingertip or using a minimally invasive patch. These invasive methods pose several problems, including being painful and potentially causing secondary infections. This study focuses on noninvasively measuring glycated hemoglobin (HbA1c) using PPG signals. In particular, the study relates to a method and a hardware design technology for removing noise that may be present in a PPG signal due to skin contact with a noninvasive HbA1c measurement device. The proposed HbA1c measurement device consists of the first sensor (PPG sensor) module including an optical barrier and the second sensor (cylindrical sensor) module for removing the skin effect. We have developed a Monte Carlo method to implement accurate, noninvasive HbA1c measurement by considering different skin properties among different subjects. Implementing this model in wearable devices will allow end users to not only monitor their glycated hemoglobin levels but also control diabetes with higher accuracy without needing any blood samples. This will be a groundbreaking advancement in modern wearable medical devices.

Ultrahigh Stretchable, Highly Transparent, Self-Adhesive, and Environment-Tolerant Chitin Nanocrystals Engineered Eutectogels toward Multisignal Sensors.

Addressing the conflict between achieving elevated mechanical stretchability and environmental adaptability is significant to a breakthrough in the practical application of flexible wearable materials. Therefore, inspired by the perceptive and protective properties of human skin, flexible wearable electronic skins (E-skins) based on deep eutectic solvent (DES) liquid and multiresponse eutectogel have been widely considered to be a promising platform for building a flexible wearable management system to achieve the purpose of "one stone, two birds". In this work, a multifunctional E-skin was designed based on an ultrastretchable, transparent, self-adhesive, and environmentally tolerant eutectogel by first incorporating cationized modified chitin nanocrystals into a covalently cross-linked polymer network comprised of the skeleton formed by a PAA polymerization network structure serving as a stretchable matrix and filled with DESs (ChCl:EG). The obtained eutectogel exhibits superhigh stretchability (up to 6707%), high toughness (17.7 MJ/m3), mechanical strength (0.48 MPa), self-adhesive, and high transparency (91.2%). Simultaneously, the multisignal sensor based on the above comprehensive properties and thermosensitive capacity exhibits a wide monitoring range, high strain/compression/temperature sensitivity, and good reproducibility. Remarkably, the sensor could be attached to rat hearts without glue or stickers for long-term monitoring of high-quality in vivo heartbeat signals. In this way, it is believed that the designed E-skin system based on eutectogel has great potential to serve as a promising platform for the next generation of flexible multisignal monitoring integrated wearable management systems.

Insertable Glucose Sensor Using a Compact and Cost-Effective Phosphorescence Lifetime Imager and Machine Learning.

Optical continuous glucose monitoring (CGM) systems are emerging for personalized glucose management owing to their lower cost and prolonged durability compared to conventional electrochemical CGMs. Here, we report a computational CGM system, which integrates a biocompatible phosphorescence-based insertable biosensor and a custom-designed phosphorescence lifetime imager (PLI). This compact and cost-effective PLI is designed to capture phosphorescence lifetime images of an insertable sensor through the skin, where the lifetime of the emitted phosphorescence signal is modulated by the local concentration of glucose. Because this phosphorescence signal has a very long lifetime compared to tissue autofluorescence or excitation leakage processes, it completely bypasses these noise sources by measuring the sensor emission over several tens of microseconds after the excitation light is turned off. The lifetime images acquired through the skin are processed by neural network-based models for misalignment-tolerant inference of glucose levels, accurately revealing normal, low (hypoglycemia) and high (hyperglycemia) concentration ranges. Using a 1 mm thick skin phantom mimicking the optical properties of human skin, we performed in vitro testing of the PLI using glucose-spiked samples, yielding 88.8% inference accuracy, also showing resilience to random and unknown misalignments within a lateral distance of ∼4.7 mm with respect to the position of the insertable sensor underneath the skin phantom. Furthermore, the PLI accurately identified larger lateral misalignments beyond 5 mm, prompting user intervention for realignment. The misalignment-resilient glucose concentration inference capability of this compact and cost-effective PLI makes it an appealing wearable diagnostics tool for real-time tracking of glucose and other biomarkers.

By-product hazelnut seed skin characteristics and properties in terms of use in food processing and human nutrition

The hazelnut seed skins (HSS) are by-products from roasting or blanching hazelnuts without direct second utilization. The generation of HSS creates an economic and environmental problem. The object of the study was a comprehensive analysis of the properties for reuse of HSS. Water extraction of industrial HSS was applied (water with sonication of the HSS for 10 min at 90 ℃). The extracts obtained were freeze-dried to facilitate analysis and future application. The HSS and their extracts were analysed. Polyphenols, antioxidants, allergens, antimicrobial properties and instrumental sensory analysis were examined. The total polyphenol content in the samples was 37.8–44.0 mg gallic acid equivalent g−1. Gallic acid was the major phenolic compound. The antioxidant capacity of the samples was 198.9–250.6 mg VCEAC g−1 (vitamin C equivalent) according to the ABTS method and 98.4–106.8 mg VCEAC g−1 in the DPPH method. The extracts inhibited all tested strains of pathogenic bacteria. Allergen content was reduced in HSS and the extracts. Instrumental sensory analysis showed differences between taste parameters and odour profile samples. HSS can be reused in food production as a bacteriostatic, antioxidant additive and sensory-creating factor due to various chemical compounds corresponding with taste and odour.

Characterising Skin Electrical Impedance Using Tape Stripping Methods: A Bioelectrical Study of a Porcine Model.

Background Recent advancements in ultra-low power electronics and wireless devices have facilitated the widespread adoption of wearable technology for fitness and health monitoring, paving the way for personalized medicine. Microneedle-based devices, comprising small epidermal patches that penetrate the skin's stratum corneum to potentially access biomarkers in the extracellular fluid of the viable epidermis, represent a promising innovation in this field. Objectives This project aimed to develop and validate a novel method to evaluate microneedle engagement in the skin in real-time. To our knowledge, there are no studies published to date that have characterized the electrical impedance of stratum corneum and epidermis using the tape stripping method to selectively remove cell layers. Additionally, no studies have been published comparing the electrical impedance of fresh to frozen-thawed porcine skin. The objective of this study was to develop and validate a novel method to evaluate microneedle engagement in skin, in real-time, that does not require processing of the tissue. Methods A tape stripping technique was employed to selectively remove the stratum corneum from fresh and frozen-thawed porcine skin samples which were then electrically characterized using an excitation frequency of 5 kHz with a peak Voltage of 1 V. Results This study demonstrated a mean impedance reduction of 97.08 ± 1.3 % for fresh porcine skin, and 98.04 ± 0.3 % for frozen-thawed porcine skin when transitioning from the surface stratum corneum to the viable epidermis. The correlation between the reduction of impedance and the number of tape strips across all 18 test sites was significant (r = 0.98, p < 0.00001). However, comparing the skin impedance of the fresh and frozen-thawed specimens showed poor equivalence, with the frozen-thawed sites approximately 5.5 times the impedance of the fresh sites before any tape stripping, and 4.19 times greater after 30 tape strips. Conclusions These findings suggest that monitoring for an interelectrode impedance decrease of greater than 95% between two projections of a microneedle device could provide a rapid and effective evaluation of skin engagement, crucial for advancing the development and clinical application of microneedle-based technologies in personalized medicine. The study also underscores the impact of the freeze-thaw process on the mechanical and electrical properties of skin, which is crucial for standardizing testing protocols.