Reduced Skin Irritation Research Articles

Infection Prevention Mask Consisting of Nanofiber Filter and Habutae Silk Fabrics.

To reduce skin irritation and allergic symptoms caused by long-term mask use, we produced a mask with a filter effect by laminating nanofibers on habutae silk fabric, a specialty of Japan’s Fukui Prefecture, using the electrospinning method. We investigated the filter characteristics of silk fabrics with different weave structures (habutae, flat crepe, and twill). We found that woven fabrics alone could not sufficiently block particles finer than 1 μm, even when the fabric layers were overlapped. Therefore, we had a nanofiber filter layer fabricated on the surface of habutae fabric by the electrospinning method at a weight of 1 g/m2. The nanofibers removed more than 94% of 0.3 μm-particles, which are similar to the size of virus particles. However, the nanofiber layer was so dense that it caused an increase in pressure drop, so we made the nanofiber layer thinner and fabricated the filter on the surface of the habutae fabric at 0.5 g/m2. A three-dimensional mask consisting of two woven fabrics, one with a nanofiber layer on the inside and the other with a normal woven fabric without a nanofiber layer on the outside, was fabricated and tested on 95 subjects. The subjects reported that the nanofiber habutae masks were more comfortable than nonwoven masks. Moreover, the silk woven masks did not cause allergic symptoms such as skin irritation.

Biocompatible All-in-One Adhesive Needle-Free Cup Patch for Enhancing Transdermal Drug Delivery.

Patch-type drug delivery has garnered increased attention as an attractive alternative to the existing drug delivery techniques. Thus far, needle phobia and efficient drug delivery remain huge challenges. To address the issue of needle phobia and enhance drug delivery, we developed a needle-free and self-adhesive microcup patch that can be loaded with an ultrathin salmon DNA (SDNA) drug carrier film. This physically integrated system can facilitate efficient skin penetration of drugs loaded into the microcup patch. The system consists of three main components, namely, a cup that acts as a drug reservoir, an adhesive system that attaches the patch to the skin, and physical stimulants that can be used to increase the efficiency of drug delivery. In addition, an ultrathin SDNA/drug film allows the retention of the drug in the cup and its efficient release by dissolution in the presence of moisture. This latter feature has been validated using gelatin as a skin mimic. The cup design itself has been validated by comparing its deformation and displacement with those of a cylindrical structure. Integration of the self-adhesive microcup patch with both ultrasonic waves and an electric current allows the model drug to penetrate the stratum corneum of the skin barrier and the whole epidermis, thereby enhancing transdermal drug delivery and reducing skin irritation. This system can be used as a wearable biomedical device for efficient transdermal and needle-free drug delivery.

Amino acid complex (AAComplex) benefits in cosmetic products: In vitro and in vivo clinical studies.

BackgroundAmino acids are major components of skin's natural moisturizing factors and play a role in regulating skin hydration and skin pH.ObjectiveThis research examines a proprietary amino acid complex technology (AAComplex) designed to help reduce skin irritation and repair skin damage.Methods In‐ vitro Scratch Assay HaCaT cells are scratched, and the wounds are imaged at different time points until the closure of the scratch wound is detected. In‐vitro 3D Reconstructed Human Tissue Evaluation The concentration of heat shock protein 27 (HSP‐27) extracted from 3D reconstructed human skin equivalent tissues and IL‐1a released to the media was determined using enzyme‐linked immunosorbent assays. In Vivo Clinical Study 37 subjects were enrolled in a split‐face study design. On test days 1, 2, 4, and 8, subjects visited the test facility to have their face assessed by facial swabbing and bio‐instrumentation measurements.Results In‐ vitro Scratch Assay The AAComplex demonstrated a strong cell renewal benefit in the HaCaT (human) cells scratch assay. In Vitro 3D Reconstructed Human Tissue Evaluation AAComplex demonstrated a significant skin repair benefit by quantifying Heat Shock Protein, HSP‐27. Induced skin irritation was significantly reduced by quantifying interleukin‐1 alpha biomarker, IL‐1a. In Vivo Clinical Study The test products delivered skin benefits by reducing visual redness and skin irritation while increasing moisturization.ConclusionThe in vitro and in vivo clinical studies demonstrated that the AAComplex technology formulated in the commercially available Skin Recovery System effectively reduced skin irritation and redness as well as accelerating the skin repair process.

A thermal activated and differential self-calibrated flexible epidermal biomicrofluidic device for wearable accurate blood glucose monitoring.

This paper reports a flexible electronics-based epidermal biomicrofluidics technique for clinical continuous blood glucose monitoring, overcoming the drawback of the present wearables, unreliable measurements. A thermal activation method is proposed to improve the efficiency of transdermal interstitial fluid (ISF) extraction, enabling extraction with a low current density to notably reduce skin irritation. An Na+ sensor and a correction model are proposed to eliminate the effect of individual differences, which leads to fluctuations in the amount of ISF extraction. An electrochemical sensor with a 3D nanostructured working electrode surface is designed to enable precise in situ glucose measurement. A differential structure is proposed to eliminate the effect of passive perspiration, which leads to inaccurate blood glucose prediction. Fabrications of the epidermal biomicrofluidic device including formation of flexible electrodes, nanomaterial modification, and enzyme immobilization are fully realized by inkjet printing to enable facile manufacturing with low cost, which benefits practical production.

Microsponge: An advanced drug delivery system

Microsponge drug delivery system (MDS) was developed to deliver the pharmaceutical ingredients efficiently at the site of administration at a limited dose. MDS is based on pore size of sponges. The action of microsponges lasts up to 12 hours. MDS is also dependent on the physicochemical properties of the drug. These are used in bone tissue engineering, for reducing skin irritation and have a self-sterilisation property. This review provides an overview regarding the characteristics, methods of preparation, properties, evaluation, applications and limitations of MDS.

Hand sanitizers: is over usage harmful ?

Sanitizers are the substances or the fluid designated to kill germs on skin and objects. As hand hygiene plays an important role in pandemic situations like COVID-19, people mostly rely on hand sanitizers than soap and water. The sanitizing effect of sanitizer depends on the ingredients such as 60-95% v/v alcohol, antiseptics, etc. The alcohol usually damages the skin by denaturation of stratum corneum proteins. The repeated or frequent use of hand sanitizers can cause skin reactions- Irritant contact dermatitis and Allergic contact dermatitis with symptoms such as burning, irritation, itching, etc. These effects can be reduced by using selected less irritating products, reducing skin irritation, use of moisturizing skin products. As microbial flora also plays an important role in human health, sanitizer overuse creates an imbalance between the good and bad bacteria in the digestive system which leads to inflammatory bowel diseases, obesity, autism, etc. As a researcher reported that sanitizer also gives an unpleasant side effect of using hand sanitizer every day and also mentioned that ‘we have to balance the benefit of sanitizer for preventing disease transmission and their potential misuse remains a challenge’.

Novel use of lip balm under tracheostomy ties to prevent skin irritation in the pediatric patient

ObjectivesTo study the effectiveness of lip balm in reducing skin irritation and preventing pressure induced injury in tracheostomy dependent children. MethodsThe skin of tracheostomy patients presenting to a pediatric otolaryngology clinic over a 12 month period from 2018 to 2019 was assessed and categorized as hyperemic blanchable (abnormal pre-pressure injury), hyperemic non-blanchable, partial thickness skin loss, or full thickness skin loss. Caregivers were instructed to apply lip balm to the skin under soft ties three times per day and with tracheostomy tie changes. Patients were followed prospectively by a tracheostomy care nurse. Results24 patients enrolled and reported daily adherence with lip balm use. Median age was 7.3 years (interquartile range, IQR, = 1.3–12.4) with 10 females and 14 males. The majority of patients (n = 20) were identified as having hyperemic blanchable skin. 96% (23/24) of caregivers reported a subjective benefit. 79.2% (95% CI: 57.8%–92.9%) of patients with hyperemic skin (n = 24) demonstrated complete resolution with continued application, and was found to be significant: all patients had skin hyperemia before application, while 20.8% (5/24) continued to have hyperemia after application (P < .001). Infants and ventilation dependent patients demonstrated recovery rates of 88.9% and 75% respectively. Median duration of follow-up was 6.3 months (IQR = 3.4–11.3). There were no documented allergic reactions, accidental decannulations, or skin deterioration in the cohort. ConclusionsLip balm appears to be a low cost, hydrophobic, and friction-reducing agent that is potentially useful in preventing at risk pressure injuries in tracheostomy dependent pediatric patients.

Ion Pair Strategy in Solid Lipid Nanoparticles: a Targeted Approach to Improve Epidermal Targeting with Controlled Adapalene Release, Resulting Reduced Skin Irritation.

Adapalene (AD) is one of the main retinoids used in the topical therapy of acne, an extremely common skin disease usually associated with psychological morbidity. However, like other retinoids, AD is frequently associated with skin irritation. To overcome the skin irritation, we proposed the encapsulation of AD in solid lipid nanoparticles (SLNs) using the ion pair strategy. The developed SLN-AD was characterized by high-performance liquid chromatography, differential scanning calorimetry, X-ray diffraction, synchrotron small-angle X-ray scattering, and transmission electron microscopy. In vitro permeation tests using porcine skin and in vivo mice skin irritation test were performed to evaluate, respectively, the drug's skin distribution and the skin irritation. The characterization studies were able to demonstrate that the proposed strategy effectively provided high AD encapsulation in SLNs and its incorporation into a hydrophilic gel. Sustained release, epidermal targeting, and less skin irritation were observed for SLN-AD gel in comparison to the marketed AD gel. The studies demonstrated that the encapsulation of AD in SLNs through the formation of an ion pair is a valuable alternative to diminish the adverse skin reactions caused by AD and can optimize patient adherence to treatment.

Investigating the Impact of the User Interface for a Powered Hip Orthosis on Metabolic Cost and User Comfort: A Preliminary Study

ABSTRACT Introduction Powered orthoses have the potential to benefit pathologic or geriatric populations by increasing the quality of their mobility, reducing metabolic cost, and helping restore functional status. However, user interface design of powered orthoses is rarely considered, and may limit their clinical impact. The aim of this study was to design and evaluate a novel user interface for a powered hip orthosis. We hypothesized that our interface design would reduce metabolic costs, reduce skin irritation, increase user comfort, and reduce pain during ambulation when compared with an off-the-shelf (OTS) interface. Methods A novel, custom-fit torso user interface was designed to have extended trimlines and load the iliac crests. This allows for improved purchase over anatomic structures and potentially improves weight distribution of the powered hip orthosis. The design was compared with an OTS user interface. Subjects ambulated in three conditions: without a powered orthosis, with an OTS interface, and with the novel interface. Five healthy subjects (23.6 ± 2.2 years) with no neuromuscular limitations ambulated on a treadmill for 6 minutes at 0.8 m/s while measuring metabolic cost for three levels of torque assistance. Subjects repeated this procedure for all three conditions. After ambulating in each interface, skin was inspected at t = 0, 10, and 30 minutes. They completed the OPUS (Orthotics and Prosthetics User’s Survey) Satisfaction with Device survey and reported pain on a 1-to-10 scale (0 = no pain). Results The novel interface reduced metabolic cost for all conditions when compared with OTS componentry. Maximal difference was at the 13% torque assistance level where the difference was 0.18 W/kg ± 0.11 (SEM) (9.48%). The novel design generally reduced pain scale and skin irritation. The average pain rating decreased from a 3/10 ± 1.17 (SEM) in the OTS condition to 2/10 ± 0.84 (SEM). The novel design generally increased OPUS Satisfaction with Device score when compared with the OTS condition; the OPUS score increased from an average of 32/45 ± 2.56 (SEM) for the OTS condition to 36/45 ± 2.1 (SEM). Discussion The novel design tended to reduce metabolic cost for all tested powered orthotic conditions. This may be explained by the novel design's more proximal trimlines and increased loading of anatomic structures. These features may be due to maximized biomechanical leverage and minimized compensatory motions during ambulation. Conclusions The user interface may impact metabolic cost of walking and user comfort. Moving forward, it should be considered an essential element of powered orthosis design. It is critical to optimize the user interface in future powered hip orthotic designs due to minimal surface area available for weight-bearing and reduced number of actuated joints. Therefore, those interested in optimizing powered hip orthotic user interface designs should focus on loading anatomic structures, including the shoulders and iliac crests, and on supporting the curvature of the lumbar spine.

Making wearable electronics sweat resistant

Wearable electronics face a constant foe: sweat. To help sweat escape and reduce skin irritation caused by wearing devices for long periods, researchers have designed electrodes from porous materia...

Enhanced Transdermal Delivery of Concentrated Capsaicin from Chili Extract-Loaded Lipid Nanoparticles with Reduced Skin Irritation.

The aim of this study was to develop lipid-based nanoparticles that entrapped a high concentration of capsaicin (0.25%) from a capsicum oleoresin extract. The solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) were strategically fabricated to entrap capsaicin without a hazardous solvent. Optimized nanosize lipid particles with high capsaicin entrapment and loading capacity were achieved from pair-wise comparison of the solid lipid mixtures consisting of fatty esters and fatty alcohols, representing small and large crystal-structure molecules combined with a compatible liquid lipid and surfactants (crystallinity index = 3%). This report was focused on selectively captured capsaicin from oleoresin in amorphous chili extract-loaded NLCs with 85.27% ± 0.12% entrapment efficiency (EE) and 8.53% ± 0.01% loading capacity (LC). The particle size, polydispersity index, and zeta potential of chili extract-loaded NLCs were 148.50 ± 2.94 nm, 0.12 ± 0.03, and −29.58 ± 1.37 mV, respectively. The favorable zero-order kinetics that prolonged capsaicin release and the significantly faster transdermal penetration of the NLC attributed to the reduction in skin irritation of the concentrated capsaicin NLCs, as illustrated by the in vitro EpiDermTM three-dimensional human skin irritation test and hen’s egg test chorioallantoic membrane assay (HET-CAM).

Improved antibacterial activity of topical gel-based on nanosponge carrier of cinnamon oil.

Introduction: Cinnamon essential oil (CEO) is a volatile oil, obtained from Cinnamomum zeylanicum has become one of the most important natural oil due to its antimicrobial activity. CEO suffers from various limitations such as instability and skin irritation. This problem has been overcome by formulating CEO-loaded nanosponges incorporated in carbopol gel with increased antimicrobial property and reduced skin irritation. Methods: The nanosponges were fabricated by solvent emulsion diffusion method and evaluated for Fourier transform infrared spectroscopy (FTIR) studies, particle size, field emission scanning electron microscopy studies (FE-SEM), in vitro dissolution studies, in vitro antibacterial studies, using agar diffusion method, in vivo antibacterial activity and skin irritation studies and stability studies. Results: Nanosponge NS1 batch was found to be in the nanosize range. FTIR studies confirmed the absence of drug-polymer interaction. NS1 confirmed a porous structure with a uniform spherical shape using FE-SEM studies. In vitro dissolution studies of optimized NS1 revealed 80% drug release in 5 h whereas, incorporating the formulation into carbopol gel showed 100% release in 5h from G1 formulation. In vitro antibacterial study of the nanosponge (NS1 and NS3) showed remarkable antibacterial activity as seen from the zone of inhibition and gel formulation G1 also showed the highest zone of inhibition with 50±1.2 mm. NS1 and G1 were stable for 2 months under accelerated conditions and 3 months under room temperature conditions. Furthermore, the in vivo and skin irritation studies were performed with selected formulation against Staphylococcus aureus , where the results confirmed the significant antimicrobial activity with no skin irritation. Conclusion: Nanosponge carriers can be more therapeutically effective for essential oils which can further be incorporated into topical gels for convenient application.

A novel composite of micelles and hydrogel for improving skin delivery of hydrocortisone and application in atopic dermatitis therapy

Transdermal drug delivery is an attractive and potentially more effective method of localized and systemic treatment with minimal side effects and greater safety than current techniques. However, a limitation of drug delivery through the skin is the presence of the stratum corneum, which inhibits the development of clinical applications. Furthermore, in order to achieve better therapeutic outcomes, a number of traditional topically-applied preparations have high drug concentrations which can lead to skin irritation and formation of lesions. The use of safer and milder hydrocortisone (HC) cream for the treatment of moderate to severe atopic dermatitis (AD) is not considered due to its low potency and poor absorption through the skin, even at a dose of 1%. Therefore, in the present study, a composite of HC-loaded micelles and carbomer hydrogel was designed to enhance transdermal HC transport to improve topical therapy of AD. Franz diffusion cell experiments indicated that this composite significantly increased the skin permeation rate and cumulative quantity of HC transferred, which were greater than a 9-fold and 50-fold increase relative to HC cream, respectively. In addition, the composite system was demonstrated to rapidly and effectively ameliorate inflammatory symptoms on an AD-like mouse model and greatly reduce skin irritation and adverse systemic effects compared to HC cream. As described above, the novel HC formulation was a feasible strategy to provide safe and effective treatment in AD therapy.

Microsponges: A Novel Strategy to Control the Delivery Rate of Active Agents with Reduced Skin Irritancy

Microsponges are particulate system which is composed by porous polymeric material. As compare to Conventional topical formulations, microsponge provide controlled release of the drug in the epidermis, it is to ensure that the drug is mainly localized and does not unduly entering the systemic circulation, it is a new area of research. The active ingredient needs to maximize the time to stay on the skin, while reducing transdermal penetration. Apart from this, there is a problem of unethical vehicles that can be viscous sticky deformation and skin irritation. One of the biggest challenges of now a days is to control irritability for a predetermined site of active agents in the human body. Microsponges delivery system is a unique technique for controlled release with low irritant involving many triggers of Mechanism for the release of drugs. The Microsponge Delivery system is a polymeric porous microspheres, which can trap a wide range of effective elements such as anti-fungus, anti-infected, anti- inflammatory agent, fragrance and essential agent. This review includes different techniques used to prepare microsponges, formulation consideration, safety consideration, drug release mechanism, and challenges with microsponge drug delivery system along with their advantages, disadvantages and applications. In the current review, we summarize the updated application and capacity of Microsponge as an effective drug-delivery system to reduce skin irritation.&#x0D; Keywords: Microsponges; quasi-emulsion solvent diffusion; Porous microspheres; Controlled release.

Microsponges enriched gel for enhanced topical delivery of 5-fluorouracil

This study aimed to develop microsponges based topical gel formulation of 5-Fluorouracil (5-FU) for the treatment of skin cancer with enhanced skin deposition and reduced skin irritation potential. Microsponges were prepared by Quasi-emulsion solvent diffusion method using ethyl cellulose and Eudragit RL 30 D; and was optimised through detailed in vitro characterisation. Brunauer–Emmett–Teller (BET) analysis demonstrated higher surface area (2.4393 m2/g) and pore volume of developed microsponges formulation. Optimised formulation showed better thixotropic and texture properties compared to commercial cream formulation, used as control for comparison purpose. Further, the optimised formulation demonstrated 5.5-fold increase in skin deposition documented via in-vivo local bioavailability study, with significant reduction in skin irritation compared to the commercial formulation. Hence, the developed microsponges based formulation seems to be a viable alternative with enhanced topical delivery of 5-FU as compared to the commercial formulation.

Fat Grafting for Improved Ileostomy Ostomy Device Fit: A Case Report

The purpose of this case study was to report the outcome of fat grafting to augment peristomal soft tissue and improve appliance fit. A 57-year-old woman with a history of Crohn's disease presented with soft-tissue deficiency and uneven contour around her ileostomy site. She was unable to properly fit an ostomy appliance, which resulted in leakage, chronic skin irritation, and frequent appliance changes. The patient underwent 2 rounds of fat grafting using fat harvested from her medial thighs and knees infused with dilute lidocaine with epinephrine. The patient noted immediate improvement after 34 cc of processed fat was injected in the first round. Appliance change frequency decreased from daily to every 3 to 4 days. A second graft of 32 cc provided 3 months later further improved appliance fit, reducing appliance change frequency to every 5 to 7 days and obviating the need to use adjustment rings and glue. Pre- and postoperative computed tomography showed increased thickness of abdominal wall subcutaneous tissues. Fat grafting around an ostomy site presents a viable option to improve contour and appliance fit with reduced skin irritation and leakage.

Flexible nano-sized lipid vesicles for the transdermal delivery of colchicine; in vitro/in vivo investigation

Colchicine (CL) is the most effective treatment of acute gout, however, it is associated with side effects in 80% of the patients at therapeutic doses, in addition, it's a water-soluble strong base (pKa ∼12.8) which ionizes at physiological gastrointestinal pH resulting in low oral bioavailability of 44%. This work employed enhancing the bioavailability and reducing the side effects of CL through combining the benefits of the transdermal route together with those of elastic lipid nano-vesicles. Transfersomes (TRs) have been studied as vehicles for transdermal drug delivery, however, poor encapsulation of drugs and drug leaking of the vesicles required complexation of CL with β-cyclodextrin (β-CD) before formulation. The composition of the designed CL-β-CD-TR was studied to balance the flexibility of the vesicles to their entrapment ability. CL-β-CD-TR were characterized for their shape, size, entrapment efficiency, elasticity, release profile, ex vivo skin permeation, pharmacological efficacy, and histopathological effect. Encapsulation efficiency of CL-β-CD complex in the vesicular formulations ranged from 42.3% to 93.8%. Particle size ranged from 70.6 nm to 138.5 nm and zeta potential ranged from 16.1 mV to 23.4 mV. The in vitro release of CL from the selected CL-β-CD-TR formulation (F3) showed a controlled, biphasic profile. Ex vivo study reported the great potential of F3 (CL-β-CD-TR) for skin permeation. In vivo experiment demonstrated that F3 (CL-β-CD-TR) possessed high biological efficacy with reduced skin irritation.

Formulasi Masker Ekstrak Daun Pepaya (Carica Papaya L.) Sebagai Anti Jerawat

Abstract Background: Mask is one of the effective facial skin cleanser. Mask has merit as deep cleansing,it’s cleaning the dirt on the skin layer deeper, binds skin cells that have died, refine pores of the skin, clean the remnants of excess fat on the surface of the skin’s face, reduce skin irritation, smoothing layer outer skin and nourish the skin, so it looks bright. This study uses papaya leaf extract has a content of the enzyme papain, alkaloids, pseudokapain, glikosid, karposid and saponins. Alkaloid contained in papaya leaves is a kind karpain which has anti bacterial activity. The advantages of the mask is the method of production can be prepared in a simple way. Masks in this study is made in the form of powder to make it easier to use and storage. Method: This study have purpose to determine the results of mask powder formulation of papaya leaf extract as an anti acne that meet the test parameters include physical, organoleptic test, water content test, pH test, and flow rate of irritation test. Result: This research is experimental observation. The results of organoleptic test mask bone-white powder, scented roses and soft textured, the results of water content of 7.5%, a flow rate of over 9 seconds, pH of 6.35. Conclusion: The results of irritation test to the 20 olunteers did not show any reaction of irritation.

Abstract 3204: Transducer array configuration optimization for treatment of pancreatic cancer using Tumor Treating Fields (TTFields)

Abstract Introduction: TTFields is an antimitotic cancer treatment that utilizes low intensity (1-3 V/cm) alternating electric fields in the intermediate frequency (100-300 kHz) that are delivered in two orthogonal directions using 2 pairs of transducer arrays. A phase II clinical trial (PANOVA, NCT01971281) showed that TTFields in combination with chemotherapy was safe in patients with locally advanced pancreatic cancer. Preclinical studies show that the effect of TTFields is intensity-dependent with a therapeutic threshold of 1 V/cm. The field distribution within the body is known to changes with array placement. Therefore, there is a need to develop principles for personalizing array placement to optimize TTFields delivery when treating pancreatic cancer. The aim of such guidelines should be to ensure delivery of maximal field intensities to the region of disease, whilst minimizing the size of the arrays placed on the body. Minimizing array size is important to enable periodic shifting of the arrays for potentially reducing skin irritation associated with TTFields therapy, as well as potentially improving overall patient comfort. Here we present a systematic study investigating how the location and size of the arrays on the abdomen influences the field distribution. Methods: To simulate delivery of TTFields to the abdomen, we used 3 realistic computerized models (from ZMT_Zurich) of: a male (DUKE 3.0); b) , a female (ELLA 3.0); and an obese male (FATS 3.0). For each model, 6-8 different layouts utilizing combinations of arrays with either 13 or 20 disks per-array were tested. The arrays were placed over the upper 6 standard abdominopelvic, and field intensity distributions within these regions were evaluated. In order to generate TTFields, an alternating voltage at a frequency of 150 KHz was imposed on the outer surfaces of the disks of each pair of arrays. The voltage was set to deliver a current of 200 mA peak to peak per-disk (total current 2.6 A for 13-disk arrays, 4.0 A for 20-disk arrays). The simulations were performed using ZMT's Sim4Life V3.0 electro-quasi-static solver. Results: In all simulations, the large arrays generated higher field intensities than the small arrays. However, On ELLA and DUKE, the large arrays covered most of the skin around the abdomen, leaving little to no room for shifting the arrays. FATs body surface is large enough so that even when large arrays are used, there is still ample space for shifting the arrays. On DUKE and ELLA, when using small arrays, the average field intensity in the abdominopelvic region over which the arrays were placed was above the therapeutic threshold of 1 V/cm. Conclusion: This work shows that TTFields array placement can be optimized to deliver therapeutic field intensities to specific abdominopelvic regions. Tailoring the size and position of the arrays based on disease site and patient size may help to improve overall treatment outcome. Citation Format: Ariel Naveh, Ze'ev Bomzon, Ori Farber, Noa Urman, Ofir Yesharim, Eilon Kirson, Uri Weinberg. Transducer array configuration optimization for treatment of pancreatic cancer using Tumor Treating Fields (TTFields) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3204.

Analysis of Consistency of Transthoracic Bioimpedance Measurements Acquired with Dry Carbon Black PDMS Electrodes, Adhesive Electrodes, and Wet Textile Electrodes.

The detection of intrathoracic volume retention could be crucial to the early detection of decompensated heart failure (HF). Transthoracic Bioimpedance (TBI) measurement is an indirect, promising approach to assessing intrathoracic fluid volume. Gel-based adhesive electrodes can produce skin irritation, as the patient needs to place them daily in the same spots. Textile electrodes can reduce skin irritation; however, they inconveniently require wetting before each use and provide poor adherence to the skin. Previously, we developed waterproof reusable dry carbon black polydimethylsiloxane (CB/PDMS) electrodes that exhibited a good response to motion artifacts. We examined whether these CB/PDMS electrodes were suitable sensing components to be embedded into a monitoring vest for measuring TBI and the electrocardiogram (ECG). We recruited N = 20 subjects to collect TBI and ECG data. The TBI parameters were different between the various types of electrodes. Inter-subject variability for copper-mesh CB/PDMS electrodes and Ag/AgCl electrodes was lower compared to textile electrodes, and the intra-subject variability was similar between the copper-mesh CB/PDMS and Ag/AgCl. We concluded that the copper mesh CB/PDMS (CM/CB/PDMS) electrodes are a suitable alternative for textile electrodes for TBI measurements, but with the benefit of better skin adherence and without the requirement of wetting the electrodes, which can often be forgotten by the stressed HF subjects.