The advent of biocompatible and biodegradable scaffolds has opened up a plethora of possibilities in neural tissue engineering. An emerging approach to overcome some existing drawbacks of neural scaffold design and functioning is a natural conductive polymeric scaffold. It is analogous to the extracellular matrix and provides an environment conducive to neural growth. This study focuses on the fabrication of soft polymeric neural scaffold, reinforced with multi-walled carbon nanotubes (MWCNTs) in a chitosan matrix, for directional neuronal growth. The scaffolds were fabricated by varying the nanofiller content as 0.5, 1.0 and 2.0. wt%, which were aligned in the chitosan matrix by an alternating bias electric field and compared with their random counterpart. The uniform distribution of the nanofillers in the matrix, good combinatorial bonding, and the directional alignment of the MWCNTs resulted in enhancement of mechanical properties and electrical conductivity in comparison to scaffolds with randomly arranged reinforcements. Additionally, the degradation kinetics of the fabricated scaffolds was tuned to the regeneration regime of peripheral nerves. After physical characterization, the biocompatibility of the designed scaffolds was evaluated by culturing HT-22 neuronal cells on the scaffolds. Along with biocompatibility, the suitability of anisotropic conductivity of the scaffolds was evaluated by the directional growth of cells cultured on aligned MWCNT–chitosan scaffold. The preferential direction of neurite growth achieved on chitosan-aligned MWCNT films and the improved mechanical and electrical properties in the MWCNT alignment direction are very encouraging for their potential use in neural tissue engineering.
Pancreatic cancer is the fourth leading cause of cancer-related deaths in the West and has a 5-year survival rate of only 2%–9%. Pancreatic cystic lesions are precursors of pancreatic cancers and a prime target for early diagnosis. Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) enables collection of cystic fluid aiming for the diagnosis of malign and premalign cysts. However, this fluid is acellular or paucicellular in 20% of cases, hampering a proper diagnosis. Here, we introduce a minimally invasive Nitinol brush that can be operated through the 413 µm lumen of a 22G FNA needle. During operation, the brush is rotated against the inner wall of the cyst, removing cells and dispersing them in the cystic fluid, where they can be aspirated through the needle. We demonstrate the brush function using three models. An in vitro cyst model was used to visualize the brushing procedure and the mechanical interaction between the brush and the wall of a spherical cavity. Ex vivo porcine intestine and bovine ovary cyst models were used to demonstrate how brushing increases the number of harvested cells with more than one order of magnitude. These results indicate the potential of cystic brushing for the minimally invasive early diagnosis of pancreatic adenocarcinoma.
A broader revelation of the mechanisms which contribute to the formation, growth, healing and remodelling of bone tissue is essential for advancing the design and development of biomaterials and devices which directly enhance bone health. Hydroxyapatite and associated calcium phosphate-based minerals play an essential role in bone tissue formation. Further insights into how biomineral crystals form, grow and integrate within bone tissue will provide key information to direct efforts in more comprehensive bone tissue engineering products and therapies. While previous studies proposed the aggregation of amorphous calcium phosphate clusters as a precursor to biological hydroxyapatite, the exact formation mechanism of the plate-like biological hydroxyapatite is still unclear. Here we report the analysis of high-resolution electron microscopy images of bone biomineral precipitated in a biological environment. We propose that 3 nm primary biologically synthesized (biosynthesized) hydroxyapatite (BHAp) single crystal units assemble and coalesce via an oriented aggregation mechanism to form larger (approximately 46 nm × 25 nm) plate-like biological hydroxyapatite mesocrystals. A better understanding of the biomineralization process can provide insights to improve the in vitro precipitation of bone biominerals with tailored properties and unique functionality. This will help to usher in the next generation of biobased biomaterials and devices to enhance the healing and remodelling of bone at the tissue, cell and subcellular level.
It should be noted that there is an absence of satisfactory medical devices for children with many types of medical conditions due to the relatively small size of the paediatric medical service market as compared with the adult medical service market, which does not incentivize many companies to focus on the particular characteristics and needs of children (Field et al., (2006). Five to six per cent of healthcare spending is for children despite the fact the children constitute 25 per cent of the overall population (Barbella, 2014). In addition, “the reality of (the medical device companies’) business structures don't allow them to (work on paediatric products) because it's not going to be something that will help their bottom line, and they have to answer to their shareholders” according to Don Lombardi (former Chief Intellectual Property Officer, Boston Children's Hospital, and founder of the Institute for Pediatric Innovation) (Barbella, 2014). The return on investment for a paediatric medical device falls below the profit goals of many medical device manufacturers (Crosse2011). In addition, medical devices are now being used with younger patients than in earlier years. Kurt Vedder (CEO, Fixes 4 Kids Inc.) noted that ‘surgeons are operating earlier in a child's life and because of that there's a need for technology, tools and devices (Barbella, 2014)'. Another limitation to the development of paediatric medical devices is that each child exhibits a different activity level, chemical composition, height, heart rate and blood pressure from his or her peers; in addition, these values will vary in a given child over time (Barbella, 2014). This limitation hinders the development of ‘generic’ medical devices for use over a wide paediatric population. Furthermore, medical device companies may not be able to readily obtain parental consent for a study; such ethical issues are considered a significant challenge to paediatric medical device development. Finally, there is also a perception of higher liability levels associated with paediatric medical devices (Barbella, 2014). Paediatricians and patient advocates have noted the possibility of adverse outcomes associated with the unavailability of paediatric medical devices (Food & Drug Administration, 2004). Many efforts at this time involve ‘working around’ the absence of an appropriate medical device for children with a repurposed adult medical device. For example, stents for use in the bile duct are repurposed for use in paediatric heart catheterization since no paediatric heart stents are available. Although FDA regulations permit ‘off-label’ or unlabelled uses of medical devices, many such devices do not precisely fit patient needs; for example, bile duct stents are associated with risk of either perforating or blocking the blood vessel undergoing treatment (Shaffer et al., 1998). A new paediatric-specific medical device may be necessary if the workaround is insufficient (e.g. a medical device scaled for paediatric use is unavailable). Additive manufacturing is a technology that was developed approximately thirty years ago for fabrication of machine tool prototypes (Boland et al., 2007). The term additive manufacturing is used to describe fabrication of three-dimensional structures via selective joining of materials in an additive layer-by-layer manner. Additive manufacturing techniques have recently been used to create patient-specific medical devices with small-scale features. For example, data obtained from magnetic resonance imaging, computed tomography or other imaging techniques may be utilized to create patient-specific implants, prostheses and medical devices. These customized medical devices may possess suitable features, including geometry, size and weight, for diagnosis and/or treatment of a given medical condition. Unlike conventional machining-based processes, medical devices with complex internal geometries (e.g. catheters with interlocking tips) may be generated via additive manufacturing processes (Azari & Nikzad, 2002; Pham & Gault, 1998; Sun et al., 2004; Webb, 2000). It is important to note that additive manufacturing processes can create structures with fewer steps and more quickly than conventional machining-based processes; the product development cycle may be lowered to 10-20% that of traditional methods per Hou and coworkers (Hou et al., 2010; Peltola et al., 2008). Additive manufacturing can overcome the limitations associated the conventional paediatric medical device manufacturing approaches since it allows for rapid processing of medical devices with patient-specific features and complex geometries at low cost and in low volumes (Field et al., 2006). The prices for many types of additive manufacturing machines have decreased in recent months, and the trend is expected to continue as additive manufacturing patents expire (Arrowsmith, 2013). A company has demonstrated processing of a prosthetic hand for a child with symbrachydactyly for between $3.80 and $5.00 (Arrowsmith, 2013). Additive manufacturing has been recently used to create an implantable customized tracheal splints out of a degradable polycaprolactone powder (Barbella, 2014). Prof. Glenn Green and Prof. Scott Hollister at the University of Michigan obtained computed tomography scans of the respiratory tracts of two paediatric patients and used this information to create splints that matched the patients’ anatomical features (Barbella, 2014). Additive manufacturing is also being widely used to manufacture prosthetic limbs due to the advantages of customization, low cost and distributed manufacturing (Zuniga et al., 2015). It is anticipated that additive manufacturing will play a growing role in manufacturing of medical devices over the coming years.
AbstractExhaled breath test is a typical disease monitoring method for replacing blood and urine samples that may create discomfort for patients. To monitor exhaled breath markers, gas biomedical sensors have undergone rapid progress for non‐invasive and point‐of‐care diagnostic devices. Among gas sensors, metal oxide‐based biomedical gas sensors have received remarkable attention owing to their unique properties, such as high sensitivity, simple fabrication, miniaturization, portability and real‐time monitoring. Herein, we reviewed the recent advances in chemoresistive metal oxide‐based gas sensors with ZnO, SnO2 and In2O3 as sensing materials for monitoring a range of exhaled breath markers (i.e., NO, H2, H2S, acetone, isoprene and formaldehyde). We focused on the strategies that improve the sensitivity and selectivity of metal oxide‐based gas sensors. The challenges to fabricate a functional gas sensor with high sensing performance along with suggestions are outlined.
The main clinical characteristics of COVID-19 are respiratory symptoms that can lead to serious cardiovascular damages and severe worsening of other medical conditions. One of the major strategies in preparedness and response to COVID 19 is effective utilization of personal protective equipment (PPE) among which the masks of different kinds are on the top of the list especially for activities in the public places. However, the underlying mechanisms of masks in preventing virus transmission have not been well identified and the current experimental data still show inconsistent outcomes that may mislead the public. For instance, the early understanding of the mask functions was limited especially in the escalating phase of the COVID 19 pandemic, resulting in quite controversial remarks on masks. Although extensive studies in mask functions have been carried out ever since the COVID-19 outbreaks, most of the investigations appear to have focused on exhalation isolation of individuals who may have been infected with the disease. Less emphasis was laid on inhalation protection from virus transmission, an important aspect that undergirds the public health policies and protective strategies. This review provides the most up-to-date information on the transmission modes of COVID-19 virus in terms of droplets and aerosols. The roles of masks in disease prevention and transmission reduction are evaluated on various types, structures and functions. More important, both aspects of exhalation isolation and inhalation protection are discussed based on virus transmission modes and the effectiveness of different types of masks under varied environmental conditions.
The modified Clinical Test of Sensory Integration and Balance (mCTSIB) is a popular protocol used to assess key sources of sensory feedback utilized during upright standing. The present study aimed to expand the age range of a previous normative sample of only young adult mCTSIB reference data collected using the Balance Tracking System (BTrackS). In total, 1,276 adults between ages 20 and 59 years old completed the BTrackS mCTSIB protocol in this study. The protocol consisted of four, 20-s trials that systematically manipulated the relative contributions of vision, proprioception and vestibular sensory systems. Total Center of Pressure Path Length results showed that females generally outperformed males in all age groups and sensory conditions. Both sexes showed reduced balance with age that started at age 50–59 years in Standard and Proprioception conditions. In the Vestibular condition, both sexes had reduced balance starting at age 30–39 years. In contrast, the pattern of reduction was different between females and males in the Vision condition. In this case, females showed a decline in balance at age 30–39 years compared to 40–49 years in males. These results provide important information demonstrating sensory feedback processing for balance can decline at differential rates based on age and sex characteristics. Percentile ranking look-up tables were also calculated as a practical tool for researchers and clinicians who regularly perform mCTSIB testing.
In this study, a triple-layered hybrid coating with self-organized microporous polymer film was developed on pure magnesium for biodegradable implant applications. Firstly, plasma electrolytic oxidation (PEO) technique was used to form a highly adherent but porous coating on magnesium metal. Secondly, the pores in the PEO coating were sealed by electrochemically depositing calcium phosphate (CaP). Finally, a self-organized microporous biodegradable polymer, poly( l -lactide acid) PLLA, was formed as a top coat on the material using spin coating method. The degradation resistance of the triple-layer coated magnesium was evaluated using electrochemical techniques in simulated body fluid (SBF). The triple-layered hybrid coating reduced the corrosion current density ( i corr ) of pure magnesium from 28.79 to 0.24 μA/cm 2 . Similarly, the electrochemical impedance spectroscopy (EIS) results showed that the triple-layered hybrid coating increased the polarization resistance ( R p ) of pure magnesium more than three orders of magnitude after 2 hr exposure to SBF (pure Mg: 4.76 × 10 +2 Ω cm 2 ; triple-layer coating: 8.67 × 10 +5 Ω cm 2 ). Although the R p of the triple-layer coated magnesium decreased with increase of immersion time in SBF (8 hr = 4.27 × 10 +5 Ω cm 2 ; 24 hr = 1.57 × 10 +5 Ω cm 2 ; 48 hr = 6.5 × 10 +4 Ω cm 2 ; 72 hr = 3.5 × 10 +4 Ω cm 2 ), it was noted that the R p of the triple-layer coated magnesium was two orders of magnitude greater than pure magnesium even after 72 hr exposure to SBF, which shows the robust nature of the coating. Further, the architecture and the dissolution mechanism of the triple-layer coating suggest that the coating has a great potential for tailoring the degradation rate of magnesium for targeted implant applications.
Health monitoring and screening have entered a period of rapid change. Popular terminology refers to this as mobile health (mHealth), which is a direct evolution of eHealth, but is really data-driven technology—sensors oriented for health care. Medical decision support through this technology is the first step towards more personalized and preventative medicine. Pressure is one of the easiest and most interesting physiological parameters to assess whether organs or biological systems are healthy in the body. Pressure recordings are commonly used for clinical diagnosis and monitoring; however, the invasiveness of current technologies and associated risks of infection limit the windows in which data can be gathered. This review discusses the importance of pressure in the body and how monitoring is performed. It also describes newer and commercially available sensors, as well as how they can be im-proved to become minimally invasive, fully wireless pressure sensors for continuous monitoring.
The development of optical biosensors based on silicon dioxide or silicon nitride transducers requires the chemical activation of their surface to achieve stable, repeatable and homogeneous binding of biomolecules. In the present study, the chemical activation of silicon dioxide and silicon nitride surfaces with 3-aminopropyl-triethoxysilane (APTES) was optimized so as to enable the immobilization of biomolecules by adsorption or covalent bonding. Chemical activation was performed with either aqueous or organic solution of APTES, and the surfaces were used to immobilize directly protein molecules by physical adsorption or further modified with glutaraldehyde to allow covalent binding of protein molecules. The protein immobilization capacity of the chemically activated silicon dioxide and silicon nitride surfaces was evaluated through incubation with mouse γ-globulins and reaction with a fluorescently labelled goat antimouse IgG antibody. By determining the surface fluorescence signal intensity, it was found that modification with 5% (v/v) APTES solution in ethanol followed by modification with glutaraldehyde provided 30% higher fluorescence signals than all the other protocols tested. In addition, this method provided the lower signal variation between different chips. To test the possible advantages of the chemical activation protocols for optical biosensing applications, they were also applied to a label-free white light interference spectroscopy sensor and evaluated through (a) real-time monitoring of the reaction between immobilized on the sensor surface mouse γ-globulins with an unlabelled goat antimouse IgG antibody and (b) a non-competitive immunoassay for the determination of C-reactive protein. The results showed that in case of antibody, physical absorption provided marginally higher binding capacity to covalent bonding.
Malaria elimination programmes are dependent on a rapid, cost-effective and portable diagnostic tool to detect and quantify malaria parasites in human blood. Herein, we report a cost-effective and portable nuclear magnetic resonance (pNMR) for malaria diagnosis. In this present study, we have developed and characterized a sensitive and low-cost novel on-chip NMR probe. This NMR probe has improved mismatching problem between radiofrequency (RF) coil and transmission line that results in en-hancement in NMR sensitivity. Developed pNMR represents a rapid, cost-effective and highly sensitive method to detect very low parasitaemia plasmodium falciparum (0.0001%) in infected human blood in comparison with other available malaria diagnosis techniques. The experimental results show that very low parasitic load can be detected rapidly by the change in the transverse relaxation rate ( T 2 ) of NMR, suggest-ing a good sensitivity. A good linear relationship with a correlation coefficient of 0.94 between the change in transverse relaxation rate ( Δ T 2 ) and the different parasitaemia ( % ) has been observed, indicating that pNMR is a potential tool for real-time, reusable and high-sensitivity analysis of malaria parasite in human blood.
Additive manufacturing (AM) represents a promising healthcare innovation. Clinicians need ready-to-use devices in short time, which means high as-built quality and low uncertainty. Medical devices need to respect stringent quality requirements ensuring safety and effectiveness. The medical practitioners often outsource the manufacturing to hub services. This study aims to assess the as-built quality of AM mandibular plate prototypes manufactured by direct metal laser sintering technology using Ti6Al4V alloy and highlights several challenges that emerge from using the commercial printing services where user does not have control over the actual manufacturing process. Verification of dimensions, morphology, surface finish and mechanical properties is conducted. Finite element analysis on computer-aided design (CAD) models was performed for stress analysis. Non-destructive analysis by micro-computed tomography (micro-CT) allowed measurement of the dimensions, ascertaining the dimensional accuracy in reference to the CAD models, and the presence of pores and internal defects, while destructive analysis allowed determination of the mechanical properties. Although no large internal defects were detected, some regions of micro-porosity and incomplete fusion of feed particles were observed. Accurate production of fine details was also a concern in the printed parts. The proposed framework estab-lishes a structured assessment scheme, which could be useful for other AM medical designs and for stakeholders involved in AM for biomedical applications.
The present work reports an enhancement in early diagnosis of DNA of prostate cancer by a rapid and sensitive biosensor. The genosensor platform was designed and fabricated using cost-effective and disposable paper-based electrodes. Herein, the bio-nano-interface was developed by immobilization of probe DNA of prostate cancer on the zinc oxide tetrapods modified paper electrode. The genosensor was characterized by scanning electron microscopy, transmission electron microscopy, synchrotron X-ray photoelectron spectroscopy, cyclic voltammetry and impedance spectroscopy. The nano-engineered genosensor was tested and found to be selective to prostate cancer. The sensor could detect as low as 1 pM of prostate cancer DNA with the linear detection range from 50 µM to 1 pM. The paper-based genosensor also proved to be advantageous in terms of easy preparation, low specimen volume, homogenous distribution of nanostructures onto the surface and cost-effectiveness. The present work demonstrates the enormous potential of DNA biosensor as a rapid and specific diagnostic tool to be used for the detection of prostate cancer DNA.
Recent advancements in sensors, device manufacturing and big data technologies have enabled the design and manufacturing of smart wearables for a wide array of applications in health care. These devices can be used to remotely monitor and diagnose various diseases and aid in the rehabilitation of patients. Smart wearables are an unobtrusive and affordable alternative to costly and time-consuming healthcare efforts such as hospitalization and late diagnosis. Developments in micro- and nanotechnologies have led to the miniaturization of sensors, hybrid 3D printing of flexible plastics, embedded electronics and intelligent fabrics, as well as wireless communication mediums that permit the processing, storage and communication of data between patients and healthcare facilities. Due to these complex component architectures that comprise smart wearables, manufacturers have faced a number of problems, including minimum sensor configuration, data security, battery life, appropriate user interfaces, user acceptance, proper diagnosis and many more. There has been a significant increase in interest from both the academic and industrial communities in research and innovation related to smart wearables. However, as smart wearables integrate several different aspects such as design, manufacturing and analytics, the existing literature is quite widespread, making it less accessible for researchers and practitioners. The purpose of this study was to narrow this gap by providing a state-of-the-art review of the extant design, manufacturing and analytics literature on smart wearables—all in one place—thereby facilitating future work in this rapidly growing field of research and application. Lastly, it also provides an in-depth discussion on two very important challenges facing the smart wearable devices, which include barriers to user adoption and the manufacturing technologies of the wearable devices.
The skin is the most exposed organ and, therefore, vulnerable to injury and wounds (Nguyen & Soulika, 2019). Wound healing is a complex tissue repair process, and failing to manage it could result in the formation of scars (Landén et al., 2016; Takeo et al., 2015). Tissue repair involves the partial tissue regeneration involving restitution of tissue components during the wound healing process (Atkin et al., 2019; Gonzalez et al.., 2016). Wound healing is a dynamic process consisting of four phases: inflammation, proliferation, DOI: 10.1002/mds3.10144
We report a flexible redox responsive polymer-based sensor for detection of reactive oxygen species (ROS). The sensor comprises multilayers of silver nanoparticles (AgNPs), carbon nanotube/cellulose nanocrystal (CNT/CNC) and a redox responsive poly (glycidyl methacrylate- co -ethylene glycol dimethacrylate- co -vinyl ferrocene), herewith called poly (GMA- co -EGDMA- co Fc) nanoferrogels. These sensor layers were printed on a micropillared polydimethylsiloxane (PDMS) substrate. The nanoferrogel sensor versatility has been demonstrated in its effective detection of ROS species, specifically H 2 O 2 , peroxylipids, and oxidative deriving species such as cholesterol and unsaturated triglycerides. The nanoferrogel ROS sensor rapidly (~1 min) responds to both H 2 O 2 and peroxylipids with a limit of detection (LOD) of ~0.060 ± 0.001 µg/ml) and 0.012 ± 0.001 µg/ml, respectively. The cholesterol oxidase and lipoxygenase-based nanoferrogel sensor were successfully evaluated for the detection of cholesterol (LOD of 0.12 ± 0.02 µg/ml) and glyceryltrilinoeate (LOD of 1.8 ± 0.2 ng/ml) standards, respectively. These enzyme-loaded ROS nanoferrogel sensors were also evaluated for quantification of cholesterol and glyceryltrilinoeate in bacon lard and olive oils. The fabricated flexible ROS sensors are versatile for quantitation of oxidative stress biomarkers, useful in myriad applications including clinical, environmental, food, and plant physiology.
Surface properties play a key role in how biomaterials interact with the environment. Surface topography has also been reported to be influential in some research, although its effect is still not well elucidated. In this study, nano-roughened polydimethylsiloxane (PDMS) substrates were developed through a chemically etched intermediate surface. Additionally, PDMS substrates containing 10–30 μm diameter micropillars were functionalized with multilayers of chitosan (CHI) and hyaluronic acid (HA) via layer-by-layer. Such substrates were submitted to cell adhesion assays with PC3 tumour cells. The characterization of these substrates was carried out using an atomic force microscopy (AFM), and some roughness parameters were estimated. Through a statistical description of the topography, we investigated the effects of these surface parameters on PC3 cell adhesion. AFM results indicated a significant modification in the PDMS surface topography and the cell adhesion assays suggest that smoother surfaces induce the PC3 cell adhesion, especially the ones with a high Hurst exponent value. In addition to the AFM analysis, the surface modification of the LbL-functionalized substrates was monitored by contact angle and UV-visible measurements. The improved wettability and the significant Alcian Blue absorbance of the functionalized substrates suggest that the HA/CHI film deposition was successfully accomplished. The LbL functionalization increased the cell capture potential of the PDMS substrates, in which lower diameter micropillars favour the cell adhesion mechanism. Although much work is still needed, the findings advance progress towards the fundamental understanding of the role of nanoscale fractal roughness in cell adhesion and can contribute to the development of new biomaterials with applications in biomedical systems, such as biosensors.
The flow behaviour and injectability of calcium phosphate cements are outcomes of the complex interplay between time-dependent processes of dissolution, nucleation and crystal growth. Their dependence on shear strains, frequencies and rates has been revealed by rheological investigation of the setting processes of a brushite cement under torsional flow. Various oscillatory torsional strain amplitudes and frequencies were seen to promote dissolution or delay crystal intergrowth compared to quiescently set cement samples. Oscillatory torsional strain amplitudes higher than the linear viscoelastic strain limit resulted in a pronounced lag in crystal intergrowth. Dissolution was enhanced and setting was promoted with increasing frequency and strain amplitude within the linear viscoelastic strain range. Changing the preshearing mode to steady torsion increased energy spent to microstructural deformation, counteracting the beneficial vibratory effect on cement setting kinetics, and produced a net retardation by the disruption of the crystal network structure. Such deformation history can be created in the cement suspension prior to injection during clinical practice by precise adjustment of the preshearing modes and parameters to enable the orthopaedic surgeon tailor the setting time, flow behaviour and injectability of calcium phosphate cements in situ without altering the cement chemistry, hence bioactivity.
Ostomies are digestive and excretory surgeries where waste is redirected to the outside of the abdomen, requiring a bag to catch excretion. Current methods use adhesives to create adhesion for 24-h usage of the ostomy bag. However, current adhesives are weak and unstable, and often lead to leakages of ostomy effluents resulting in various clinical complications including irritant dermatitis and infection. Due to these challenges, no commercially available product provides strong enough adhesion nor mechanical softness to prevent skin damage from ostomy leaks. In this work, we introduce a hydrogel ostomy adhesive (HOA) made from a tough double-network hydrogel based on polyacrylamide and sodium alginate that strongly adheres onto the skin for over 24 h and prevents leaks by maintaining fluid-tight sealing against regular bodily movements. The adhesion of HOA to abdominal skin is achieved by the topological adhesion formed by a biopolymer chitosan solution. The HOA’s robust adhesion of an ostomy bag is demonstrated on ex vivo porcine skin and in vivo human skin and is compared with existing commercially available ostomy bag adhesives.
