Penetration Area Research Articles

Comparative study of SAW and ASAW process on ASTM A709 Grade 36 steel welds

Welding is a versatile fabrication process used in manufacturing industries for joining structural components. The welded structure's capacity to carrying loads is affected by bead characteristics and process parameters. In this research work, the influnce of the Submerged Arc Welding and Advanced Submerged Arc Welding process on heat input, area of penetration, reinforcement, and heat affected zone, electrode melting rate, electrode and plate melting efficiencies, flux consumption, metal deposition rate, the microhardness of weld metal and HAZ, the microstructure of weld metal zone and power consumption have been studied. The experiments were carried out with the bead on plate (BOP) technique in ASTM A709 Grade 36 steel. The Advanced Submerged Arc Welding process reduces the heat input and area of heat affected zone. At the same time, it increases the area of reinforcement height, electrode melting rate, electrode melting efficiency, metal deposition rate and flux consumption. The microhardness of both zones of the Advanced Submerged Arc Welding process is higher than the Submerged Arc Welding process. Moreover, the microhardness of the heat affected zone is higher than the weld metal zone. The microstructures show the ferritic structure with columnar grains, whereas the column size reduces in the Advanced Submerged Arc Welding process. The Advanced Submerged Arc Welding process reduces the power consumption by 20.59% compared to the Submerged Arc Welding process.

АНАЛИЗ СИЛОВОГО ВЗАИМОДЕЙСТВИЯ ДИСКОВОГО НОЖА С ДРЕВЕСИНОЙ ПРИ БЕССТРУЖЕЧНОМ ДЕЛЕНИИ

The interaction of a circular knife with wood is a simple but interesting topic. The article will analyze the interaction of a knife with wood. A program is described that allows determining the preliminary deformation force for various disk shapes: rings, prisms, spheres, according to a given penetration area. Two periods of pressing are considered, both continuous and hollow, with sharply different pressure changes. Talk about the process of deformation of wood during compression along the fibers. Conclusions are drawn to reduce the cutting force. To establish the relationship between the degree of pressing and the axial stress (division force), a series of experiments were carried out on a testing machine using standard samples of pine and poplar wood. An experimental curve is constructed in a system of rectangular coordinates. With the help of a mechanical dynamometer, the total force of the division of softwood was determined. Theoretical substantiation of the obtained force of cutting with a disk knife is carried out. It has been established that the total effort of cutting soft wood is on average less than when sawing with round saws by 20-30%. It was also found that the smallest contact spot of the cutting disc with wood up to a contact angle with wood of 90 ° changes insignificantly and the total cutting force decreases with a decrease in the contact angle.

Development of an Immunoassay Detection System for Koi Herpesvirus Using Recombinant Single-Chain Variable Fragments

Koi herpesvirus (KHV) is a highly contagious virus that causes high mortality in koi and common carp, leading to a reduction in production worldwide. Recent diagnostic tests based on molecular methods alone (nucleic acid amplification) and indirect immunoassay methods (antibody detection) can be confirmed over KHV infections or prior exposure and latent infections. Unfortunately, there is no established method to detect KHV virus particles, especially when virus titers are low. Therefore, we propose an alternative, direct immunoassay method for viral detection using a single-chain variable fragment (scFv), a specific region of IgG antibodies that binds specifically to KHV particles. The results of functional analyses indicated that four putative scFv candidates, C5, F8, F6, and E4, were specific to KHV, but only F6 and C5 had a high binding affinity. The binding characteristics were confirmed by indirect competitive and sandwich enzyme-linked immunosorbent assays, which indicated that F6 and C5 have a broad penetration area to the binding region and share a similar epitope with commercial KHV monoclonal antibodies. These characteristics were further confirmed by their interactions with purified KHV coat protein by indirect ELISA and Western blot analyses. In conclusion, the F6 and C5 scFvs have adequate binding affinity to KHV particles to permit their use in immunoassays.

AM60-AlN Nanocomposite and AM60 Alloy Corrosion Activity in Simulated Marine-Coastal Ambience

The initial stages of AM60-AlN nanocomposite and AM60 corrosion behaviors were compared over 30 days of exposure to solution (NaCl, Na2SO4 and NaHCO3), simulating the marine-coastal environment (SME). The incorporation of AlN nanoparticles (1.0 wt.%) in the AM60 alloy matrix favored the lower roughness of the AM60-AlN, associated with the grain refinement in the matrix. During the immersion of the alloys, pH of the SME solution shifted to alkaline values >9, and therefore, the solubility of AlN aluminum hydroxide phases were raised, followed by a slightly higher release of Mg-ions and corrosion rate increase. The chloride ions attributed to the unstability of the Al-Mn phase and Al(OH)3 corrosion product was formed in a low content. The composite AM60-AlN presented lower value of the electrochemical noise resistance (Rn), suggesting that the corrosion process occurs with less difficulty. The localized corrosion near the Al-Mn cathodes seems to be stronger on the composite surface, in area and depth of penetration. The corrosion current fluctuations suggested that the corrosion is a weakly persistent process, dominated by the fractional Gaussian noise (fGn).

Effect of Fuel Physicochemical Properties on Spray and Particulate Emissions.

To investigate the effect of fuel physicochemical properties on spray and particulate emissions, fuel spray characteristics were tested on a constant volume chamber (CVC) test rig using a high-speed camera method to investigate the effect of different injection and ambient pressures on spray characteristics. In the engine bench tests, the effects of particulate emissions from five different diesel fuels with different physicochemical properties were analyzed under low-, medium-, and high-load steady-state conditions and 5 s transient loading conditions. The test results showed that the spray tip penetration of different CNs results from the combined effect of the fuel properties. The spray cone angle of the five fuels increased with the increase of injection and ambient pressure, and the impact of ambient pressure on the spray cone angle was more prominent. Spray tip penetration and spray projection area increase with increased injection pressure and decrease with increased ambient pressure; compared with spray tip penetration, the spray cone angle has more influence on spray projection area, especially near-field spray cone angle as the primary influence factor. Fuels with different ignition characteristics have other effects on particulates at different loads. At low loads, choosing CN = 55.3 fuel improved the number and mass of particulates; at medium and high loads, choosing CN = 51 fuel reduced the number of particulate emissions. Fuels with different volatilities have different effects on particulates at other loads. At low loads, CN = 54.9 fuel was chosen with moderate volatility and aromatic content. At medium and high loads, the volatility of the fuel had a lower weight on particulates, and the aromatic content had a higher weight. Under the transient loading condition of 5 s, using fuel with a higher CN, good volatility, and lower aromatic content can appropriately reduce the number of particulate emissions.

Investigating the Effect of Cooling Air Passage on the Temperature Distribution in Turbine Blades

This paper was carried out to study the effect of the velocity ratio of cooling air on the temperature distribution in the turbine blade passage0The experimental and computation method gives a clear picture of the penetration area and the temperature distribution in the passage. All the calibration of the instrument and the laws of the five hole probe may be notes in the section test rig. Several cases have been studied in this research by using three-velocity ratio (VR=0.5, 1and 2), and three different locations (99% ,90% and 75%) from the end wall with the jets angle θ= 450.the hole diameter (d= 0.1 cm). The procedure solves the governing equation numerically by using the finite volume method semi implicit method for pressure-linked equation. Therefore the present results show an accepted agreement if compared with experimental work. The maximum temperature occurred of VR=0.5 and the jet location (99%) from the end wall .Therefore the temperatures are fluctuated at the core, and decreased gradually from the jet core to outside. The temperatures are increase with decrease the velocity ratio at the same the jut location from the axial chored.

Experiments on the Novel Chord-Edge Cutter to Break Rock with Higher Efficiency and Its Field Application

Summary Aiming at the difficulty of penetration in hard-plasticity formation represented by the Mahu oil field, a new type of chord-edge cutter is proposed. Through theoretical derivation and quantitative analysis of specific unit pressure (SUP) and breaking area, the penetration and rock-breaking area of the chord-edge cutter are studied, which clarifies that the rock-breaking efficiency of the chord-edge cutter is higher than that of the conventional cutter. The first part of the laboratory experiment investigated the drilling efficiency of two mini-bits on a special sample. The results show that the chord-edge cutter mini-bit has higher efficiency than a conventional mini-bit. The second part of the laboratory experiment investigated the influence of rate of penetration (ROP), revolutions per minute (RPM), and rock types on the drilling performance of chord-edge cutter mini-bit. The data show that the chord-edge cutter is more suitable for drilling hard-plastic rocks. It also reveals that the higher the RPM, the lower the stick/slip vibration, but the RPM above a certain value will lead to an increase in lateral vibration. ROP and weight on bit (WOB) are positively correlated. And the higher the drilling speed, the higher the stick/slip vibration and lateral vibration. To verify these conclusions, a field test is carried out in the hard-plastic formation of a well in the Mahu. In this test, compared with a conventional polycrystalline diamond compact (PDC) bit, a roller-cone bit, and a hybrid bit, the chord-edge cutter bit has the best drilling effect. Further, it is found that when using the chord-edge cutter bit, the high RPM and proper control of WOB can achieve a better drilling efficiency. This rule is mutually confirmed with the conclusion of the laboratory experiment. After the above research and its implementation, it can be concluded that the novel chord-edge cutter bit can achieve the research goal of higher efficiency, which provides a new idea to overcome challenges in the hard-plastic strata.

Microstructure as a key parameter for understanding chloride ingress in alkali-activated mortars

This study aims to evaluate the influence of microstructural properties on the chloride diffusion resistance of alkali-activated materials (AAMs) based on blast furnace slag and/or fly ash, with variable activator doses (represented as Na2O%). Resistance to chloride penetration was tested using accelerated chloride penetration (NT BUILD 443) and chloride migration (NT BUILD 492) tests. Addition of slag to alkali-activated mortars mainly based on fly ash reduced porosity and chloride permeability. Chloride penetration decreased with increasing Na2O%, but porosity and pore structure did not follow the same trend. The pore threshold (dth) and critical pore radius (rcrit) determined by mercury intrusion porosimetry had a good correlation with the chloride diffusion coefficient. Both the quantification of reaction products and the correlation between chloride penetration and pore surface area indicated that physical chloride adsorption on the C-A-S-H/N-A-S-H gel surfaces predominated over chemical chloride binding.

Biodiesel derived from waste cooking oil in blends with ultra-low sulphur diesel and its spray macroscopic properties under split injection strategy

There is a significant interest to evaluate alternative injection strategies in order to improve the performance of biofuels and its blends in internal combustion engines as a way to decarbonize the transport sector, particularly in high potence demand niche. Biodiesel is the renewable analogue for petroleum diesel but the performance assessment of its blends from related to their spray macroscopical properties is scarce in the literature. This article evaluates the effect of Waste Cooking Oil Biodiesel (WCO) produced at semi-industrial scale in blends (B05, B10, B20) with commercial Ultra Low Sulphur Diesel (ULSD) on the fuel spray macroscopic properties such as penetration, angle, and area when a split injection strategy is used in a constant volume chamber under non-reactive and evaporative conditions using an injection and back pressure of 120 MPa and 5 MPa, respectively. These results were analysed in conjunction with relevant physicochemical properties of the fuels to identify the optimum diesel-WCO biodiesel blend, that could be implemented in a conventional diesel engine. It was observed that the increase of density and viscosity directly influences spray tip penetration, whereas surface tension affects spray angle. The values of spray penetration and spray area of all fuels during the second injection were higher than those of the first injection. Accordingly, the first injection event provokes an improvement mixing process of the second injection event in all cases. The values of spray penetration and area corresponding to B10 and B20 were higher than those of B5 and ULSD in both injection events at all times. Therefore, the split injection could be an effective strategy to improve the mixing process of biodiesel blends as well as the efficiency and emission performance in conventional diesel engines.

Influence of the magnetic field on the melting and solidification behavior of narrow-gap laser welding with filler wire

This study analyzed the influence of magnetic induction intensity on the plasma electron temperature distribution and the molten pool flow behavior by high-speed imaging and spectral analysis. With the increase in magnetic induction intensity, the plasma high-temperature center region gradually increased, and the plasma electron temperature increased from the bottom of the groove to the edge of the groove. The magnetic field showed a stirring effect on the molten pool. Certain magnetic field intensities can make the molten pool more uniform and flow more stable. Compared with the penetration depth and penetration area size of the weld with or without a magnetic field, the penetration depth and penetration area of the weld under the magnetic field increased. A certain range of magnetic induction intensity can be coupled with other process parameters to achieve an ideal effect and form a weld.

Gap volume and sealer penetration of C-shaped root canals obturated with cold hydraulic technique and calcium silicate sealer.

This study compared the gap volume and sealer penetration in C-shaped root canals prepared with adaptive core rotary files and obturated with cold hydraulic compaction using calcium-silicate sealer, warm vertical hybrid compaction, or lateral compaction using epoxy-resin sealer. Thirty-six extracted mandibular molars with pulpal floor configuration Types I and III were used. The teeth were prepared using XP-Shaper and XP-Finisher and obturated with: group 1: cold hydraulic compaction/calcium silicate, group 2: warm vertical hybrid compaction/epoxy resin, or group 3: lateral compaction/epoxy resin. The gap volume was evaluated using μ-CT. The sealer penetration depth and area were evaluated using confocal laser scanning microscopy. The gap volume in groups 1, 2, and 3 was 0.82%, 0.24%, 0.80%, respectively, which were not significantly different (p> 0.05). The gap volumes in the obturated C-shaped canals were not significantly different among the CHC/CSBS, WHC/ERS, or LC/ERS groups. CHC/CSBS was the most convenient technique.

Effect of different activation methods on the intratubular penetration of CaOH2 paste: Ex-vivo analysis by confocal laser scanning microscopy.

The aim of this study was to evaluate the maximum penetration depth (MPD) and penetration area (PA) of CaOH2 paste agitated by different methods and to measure the pH after performing these methods. Fifty-five mandibular premolars were divided into control, GL and 4 experimental groups, GEC, GXP, GEDDY and GI (n= 11), where the paste was agitated with Easy Clean, XP-endo Finisher, EDDY and Irrisonic, respectively. The canals were instrumented and irrigated with NaOCl. The paste was manipulated with propylene glycol and rhodamine B dye. Root sections were examined using confocal laser scanning microscopy. There was no difference between groups regarding PA (p> 0.05). At 5 mm, MPD was greater in GEC than in GL or GEDDY, and greater in GI than in GL (p< 0.05). At 2 mm, MPD was greater in GEC than in the other groups (p< 0.05). In conclusion, both Easy Clean and Irrisonic promoted deeper paste penetration and were associated with higher pH levels.

Carrier-Based Obturation: Effect of Sonication Technique on Sealer Penetration in Dentinal Tubules: A Confocal Laser Scanning Microscope Study

(1) Background: In endodontics, anatomical complexities and irregularities in the root canal system may interfere with sealer penetration, increasing the risk of treatment failure. This work aimed to investigate the effects of sonicated Thermafil (Dentsply, Tulsa Dental Specialties, Johnson City, TN, USA) on sealer penetration into the dentinal tubules. (2) Methods: Thirty teeth with single round-shaped root canals were used to compare Sonicated Thermafil with sonication (ST—10 teeth), System B (EIE Analytical Technology, Orange, CE, USA) (SB—10 teeth), and Thermafil without sonication (T—10 teeth). A confocal laser scanning microscope (CLSM) was used to determine the depth, area, and percentage of sealer penetration into the dentinal tubules. (3) Results: ST showed the deepest average penetration at 6 mm from the apex compared to SB (p &lt; 0.01) and T (p &lt; 0.01) and at 3 mm compared to SB (p &lt; 0.01). In addition, it had the highest penetration values at both levels compared to SB (p &lt; 0.01) and T (p &lt; 0.05) and a higher penetration area at 6 mm compared to T (p &lt; 0.05) and SB (p &lt; 0.05). (4) Conclusion: Sonic activation can improve the carrier-based obturation technique thanks to deeper sealer penetration and thus better retention of materials.

Visualization and comparison of methane and hydrogen jet dynamics using schlieren imaging

In the present work, methane (CH4) and hydrogen (H2) jet dynamics from a hollow-cone piezoelectric injector are experimentally investigated. The jet characteristics are studied under the effect of (1) pressure ratio, which is the ratio of the injection pressure (Pi) to the chamber pressure (Pch), (2) needle lift, and (3) nozzle geometry (hollow-cone outwardly opening nozzle without any caps versus the same nozzle with a single-hole cap). Z-type schlieren imaging is applied in a constant volume chamber equipped with optical access. The main characteristics of CH4 and H2 jets, i.e., penetration and cross-sectional area, are compared via MATLAB-based image post-processing. The novelty originates from the comparison of H2 and CH4 jet characteristics in similar conditions, from two different nozzle geometries, and investigating the effect of pressure ratio by changing the injection pressure and chamber pressure, separately. The results show that a 20% increase in the pressure ratio leads to at least a 13% increase in the H2 jet penetration and a 20% increase in its cross-sectional area. For CH4, the same rise in the pressure ratio enhances the jet penetration by at least 17% and its cross-sectional area by at least 21%. Change of Pi or Pch at the same pressure ratio leads to at least 3% and 10% difference in H2 and CH4 jet penetration, respectively, and at least 4% difference in their cross-sectional area. Increasing the needle lift leads to a greater jet penetration and cross-sectional area because of a larger injected mass and thereby a larger jet momentum, as well. Moreover, placing a single-hole cap on the hollow-cone outwardly opening nozzle causes approximately 50% pressure loss. However, the single-hole jet can still provide deeper penetration and enough cross-sectional area for efficient mixing. Overall, the comparison of H2 and CH4 jet characteristics shows that despite the large differences between their physical properties, jet penetrations are almost similar whereas the H2 jet possesses at least a 3.5% larger cross-sectional area than CH4.

Intratubular penetration capacity of HiFlow bioceramic sealer used with warm obturation techniques and single cone: A confocal laser scanning microscopic study

ObjectiveThe aim of this paper was to evaluate the intratubular penetration area of a bioceramic sealer, using continuous wave (CW), vertical condensation (VC) with two different types of gutta-percha (conventional (NG) and bioceramic-coated (BG)) and single cone (SC) technique with BG gutta-percha, in different root thirds. MethodsA total of 150 mature single-root human teeth (including incisors, canines and premolars) were prepared and randomly divided into five groups (n = 30). Teeth were filled using a bioceramic sealer (TotalFill BC Sealer HiFlow ®) and two different types of gutta-percha, with CW and VC techniques, the teeth in the control group were filled with SC technique and BG gutta-percha. The teeth were sectioned and evaluated as one-third portions in each case under a confocal laser microscope. The penetration area measurements were carried out with the Autocad ® programme. Data was analyzed using the one-factor ANOVA test (p < 0.05) and Post Hoc Test (p < 0.05). ResultsThe ANOVA Test showed significant differences in the penetration areas of the five obturation techniques (P < 0.05). The Post Hoc Test exhibited significant differences in multiple comparisons (P < 0.05). There was more dentinal tubule penetration in the coronal third than in the apical third in all techniques. ConclusionsThe intratubular penetration of the bioceramic sealer was influenced by the obturation techniques tested, but not by the different gutta-percha tested. There was more penetration of sealer in the warm obturation techniques than the SC, regardless of the type of gutta-percha used.

Spray evaporation characteristics of isopropanol-butanol-ethanol (IBE)/diesel blends in a constant volume chamber

As an intermediate fermentation product of butanol, isopropanol-butanol-ethanol (IBE) can be used as an alternative fuel for diesel directly to reduce the separation and purification costs during the butanol fermentation process. However, how the properties of IBE affect the spray evaporation characteristics of diesel is rarely studied. In this regard, IBE was blended into diesel at various volumetric ratios and then tested in a constant volume chamber using Mie scattering method. The experimental results show that after blending IBE into diesel, the spray evaporation characteristics improve noticeably. The more IBE blended into diesel, the shorter liquid spray penetration and smaller spray area are. However, the reduction of the liquid spray penetration and spray area are not linear, they exhibit a huge drop when the IBE to diesel ratio increases from 60% to 80% in volume. With more IBE blended into diesel, the time for the spray to reach the stable stage decreases. Results also show that the ambient temperature has great effects on both the spray evaporation of pure diesel and IBE/diesel blends. As the ambient temperature rises, their spray jets become smaller, and the corresponding liquid spray penetration become shorter. That means elevate the ambient temperature can further improve the spray evaporation of IBE/diesel blends.

Alterations to the synovial invaginations of the navicular bone are associated with pathology of both the navicular apparatus and distal interphalangeal joint when evaluated using high field MRI.

Limited information exists regarding associations between distal interphalangeal joint (DIPJ) abnormalities and synovial invagination changes in the distal sesamoid (navicular) bone. This retrospective, analytical study aimed to measure specific characteristics of the synovial invaginations of the navicular bone to determine whether any single characteristic was associated with abnormalities in the DIPJ or navicular apparatus (NA) using high field MRI and a sample of 200 horses' feet. The DIPJ and NA were graded independently by three scorers. The grades were averaged, creating a global pathology score for the DIPJ, NA, and synovial invaginations. Higher global scores represented more severe pathology. The number of invaginations, depth of penetration, invagination shape, and cross-sectional area (CSA) of the largest invagination were recorded. Interobserver agreement was measured using Cohen's Kappa. Associations of global scores of the DIPJ and NA with individual invagination characteristics were assessed using linear mixed modeling. A significant relationship was found between the number of invaginations and global DIPJ score, with higher invagination numbers associated with higher DIPJ scores. For invagination depth and CSA, a significant relationship was noted with global scores of both the DIPJ and NA. Reliable relationships between the shape of synovial invaginations and global scores of DIPJ and NA were not found, likely due to poor interobserver scoring (0.305). These findings suggest that primary DIPJ disease and NA pathology should be considered when noticing alterations to navicular synovial invaginations on MRI. This contrasts traditional views that synovial invagination abnormalities are indicative solely of NA pathology.

Development of Nanomaterials to Target Articular Cartilage for Osteoarthritis Therapy.

Osteoarthritis (OA) is an obstinate, degradative, and complicated disease that has drawn much attention worldwide. Characterized by its stubborn symptoms and various sequela, OA causes much financial burden on both patients and the health system. What’s more, conventional systematic therapy is not effective enough and causes multiple side effects. There’s much evidence that nanoparticles have unique properties such as high penetration, biostability, and large specific surface area. Thus, it is urgent to exploit novel medications for OA. Nanomaterials have been sufficiently studied, exploiting diverse nano-drug delivery systems (DDSs) and targeted nano therapeutical molecules. The nanomaterials are primarily intra-articular injected under the advantages of high topical concentration and low dosage. After administration, the DDS and targeted nano therapeutical molecules can specifically react with the components, including cartilage and synovium of a joint in OA, furthermore attenuate the chondrocyte apoptosis, matrix degradation, and macrophage recruitment. Thus, arthritis would be alleviated. The DDSs could load with conventional anti-inflammatory drugs, antibodies, RNA, and so on, targeting chondrocytes, synovium, or extracellular matrix (ECM) and releasing the molecules sequentially. The targeted nano therapeutical molecules could directly get to the targeted tissue, alleviating the inflammation and promoting tissue healing. This review will comprehensively collect and evaluate the targeted nanomaterials to articular cartilage in OA.

The Impact of Laser-Activated and Conventional Irrigation Techniques on Sealer Penetration into Dentinal Tubules.

Objective: The present study was aimed at comparing the efficacy of 1-hydroxyethylidene-1, 1-diphosphonic acid (HEDP) and ethylenediaminetetraacetic acid (EDTA) by using various final irrigation techniques on penetration of sealer. Background: Traditional irrigation of root canals with a syringe limits the ability of sealer penetration. Various irrigants and activation techniques, including sonic and ultrasonic devices and various kinds of lasers, have been introduced to improve penetration of sealers into dentinal tubules. Methods: One hundred mandibular premolars were selected. Final irrigation was performed with HEDP or EDTA by conventional syringe irrigation (CI), EndoActivator (EA), passive ultrasonic irrigation (PUI), photon-induced photoacoustic streaming (PIPS), and shock wave-enhanced emission photoacoustic streaming (SWEEPS) methods (n = 10). After obturation of root canals with the EndoSequence BC Sealer, samples were evaluated using a confocal laser scanning microscope (CLSM), which enabled measurement of the maximum depth, percentage, and penetration area. Tests performed for analysis included the Kruskal-Wallis H and Mann-Whitney U tests. Results: In the EA method, the penetration percentage achieved using HEDP was significantly higher than EDTA at both sections (p < 0.05). Irrespective of the final irrigation solution employed, the PUI, PIPS, and SWEEPS techniques exhibited greater tubule penetration values compared with the CI and EA techniques (p < 0.05). Conclusions: HEDP and EDTA showed similar effects on the amount of penetrated sealer into the dentinal tubules, and the PUI, PIPS and SWEEPS methods provided enhanced EndoSequence BC Sealer penetration compared with the CI and EA methods. This study was approved by the Near East University institutional review board (#2020/86-1225).

LB951 Assessing penetration, delivery, and mode of action of dissolving microneedle patches for reducing under-eye wrinkles using reflectance confocal microscopy

The purpose of this study was to visualize penetrance of self dissolving microneedles into different layers of the epidermis, visualize subsurface anatomical changes and calculate distance between microneedles and visualize deposition of drugs in the dermis. We recruited 8 subjects of different age groups to better understand how the microneedling patches containing hyaluronic acid and botulinum polypeptide-1 work under the eye to reduce wrinkles. Clinical pictures were taken and reflectance confocal microscopy (RCM) was performed before application and after removal of the patch to view subsurface anatomical changes. Each under eye patch was left for at least 6 hours overnight before performing a confocal scan. In 1 subject, we performed confocal microscopy after 1 hour and 2 hours of patch application to better understand the mode of action of microneedle patches. We were able to visualize the area of penetration of microneedles into the epidermis. Distance between microneedles was calculated. We were clearly able to visualize deposition of drugs into the dermis in 3 subjects, as well as in the subject that was confocaled sequentially after 1 and 2 hours. Dissolving microneedle patches allow for targeted drug delivery and are available over the counter for various aesthetic reasons, including wrinkles. RCM can be a useful tool to study microneedle penetration and drug delivery. Furthermore, it can help visualize and determine which areas of the skin would be ideal for transdermal drug delivery.