Gelatin Surface Research Articles

Micro-fluidic covalent immobilization of multi-gradient RGD peptides on a gelatin surface for studying endothelial cell migration.

Collective endothelial migration is a hallmark of wound healing, which is regulated by spatial concentration gradients of extracellular biochemical factors. Arginine-glycine-aspartate (RGD) peptides play a vital role in regulating cell migration through specific binding to integrins. In this study, a micro-fluidic technology combined with a photopolymerization technique is developed to create gelatin methacryloyl (GelMA)-based substrates with various concentration gradients of RGD peptides. The capability of generating linear and nonlinear RGD concentration gradients was quantitatively verified through numerical simulation and immunohistochemical quantitative experiments. The results of the concentration gradients show a strong concurrence between the immunohistochemical quantification experiments and numerical simulations. Furthermore, endothelial migration experiments were conducted with various concentration gradients of RGD peptides. We have observed that endothelial cells on the surface of gels with a linear concentration gradient exhibit a larger cell area, a longer cell perimeter, and more stress fiber density. Furthermore, the cells demonstrate directional alignment and migration towards regions with a higher RGD concentration. High concentration gradients significantly enhance endothelial cell migration, consistent with observations on surfaces of gels with nonlinear concentration gradients. In brief, we proposed a simple and effective micro-fluidic photopolymerization technique capable of generating diverse concentration gradients of RGD and probing their effects on cell migration. The results suggest that regulating the RGD peptide concentration gradients can alter the migration of endothelial cells, showing potential for promoting wound healing.

PH-shifting treatment improved the emulsifying ability of gelatin under low-energy emulsification

The effects of pH-shifting treatments (pH 3, 5, 7, 9, and 11) on the stability of gelatin emulsions made by low-energy stirring were investigated. pH-shifting treatments significantly enhanced the ESI and EAI of the emulsion (P < 0.05) and reduced its particle size (P < 0.05) under low-energy emulsifying conditions. The pH11–7 shifting treatment significantly increased the degree of depolymerization and the level of ordered structure of gelatin (P < 0.05). These transformations resulted in a significant increase in the exposure of hydrophobic and negatively charged residues (P < 0.05) on the surface of gelatin, facilitating a faster adsorption rate of gelatin onto the oil-water interface as well as an increase in the amount of gelatin adsorbed at the interface. Moreover, the alkali-shifting treatment promoted the formation of a thin viscoelastic interfacial film, which contributed to the enhanced stability of the emulsion.

Fabrication of stable hydrogel microspheres with hydrophobic shell using water-in-water (W/W) Pickering emulsion template

Hydrogel microspheres are promising for food applications. The water-in-oil (W/O) emulsion template is commonly used to prepare the hydrogel microspheres. However, this method often involves synthetic surfactants and toxic organic solvents to remove the oil phase. The swelling problem of the resultant microspheres is another obstacle. In this study the water-in-water (W/W) emulsion template of gelatin-in-dextran was used to prepare the hydrogel microspheres, without the addition of surfactants, toxic reagents and high energy input. To prevent swelling, zein particles modified with alginate were served as a hydrophobic shell of the gelatin core. The formation evolution of these core–shell microspheres and its relevant factors including phase behavior of the immiscible gelatin/dextran, the binding of zein/alginate and the addition of the modified zein particles were investigated. It was found that small amount of alginate could induce zein particles to absorb on the gelatin surface, whereas the excess led to absorption competition. When using 0.6 wt% particles with zein/alginate ratio of 1:0.5, the ideal core–shell microspheres which were fully covered by the particles and with a self-supporting architecture in uniform size (18.8 ± 0.1 μm) and spherical shape were obtained. These microspheres showed remarkable stability under the conditions of heat treatment, varied pHs and salt concentrations and long-term storage either in refrigerator or room environment. Their sizes were easily manipulated by adjusting the concentration and molar mass of the biopolymers. It is believed that the desired stability and tunable sizes of these edible core–shell microspheres could contribute the development of their applications in foods.

Effect of cold plasma treatment on physicochemical and functional properties of gelatin extracted from buffalo bone

The present investigation was carried out to evaluate the impact of cold plasma at various power levels (170, 200, and 230V) and for different times (5, 10, and 15 min) on gelatin extracted from buffalo bone to ascertain the difference in physicochemical and functional parameters of untreated and cold plasma treated gelatin. An increase in porosity and angle of repose, and decrease in flow characteristics were observed. The etching phenomenon of cold plasma enhanced surface area, and hence increased viscosity. An increase in the elastic behaviour of gelatin was detected from G' (Storage Modulus) and G" (Loss Modulus). The relative crystallinity dropped to 39.45% in the control sample and 36.9% in the treated samples on XRD as an effect of active plasma species. FTIR revealed minor differences in peak intensity, without a new chemical group. Gelatin's microstructure and surface topography were revealed via SEM investigation. The DSC analysis demonstrated an increase in glass transition (Tg) temperature of gelatin molecules due to alteration in chain dynamics and intermolecular interactions. Moreover, gelatin films prepared from cold plasma treated gelatin showed significant improvement in their tensile strength and mechanical properties suitable for development of packaging films.

Osteogenic potency of dental stem cell-composite scaffolds in an animal cleft palate model

ObjectiveTo evaluate the osteogenic potency of stem cells isolated from human exfoliated deciduous teeth (SHED) in polycaprolactone with gelatin surface modification (PCL-GE) and poly (lactic-co-glycolic acid)-bioactive glass composite (PLGA-bioactive glass (BG)) scaffolds after implantation in a rat cleft model. MethodsCleft palate-like lesions were induced in Sprague-Dawley rats by extracting the right maxillary first molars and drilling the intact alveolar bone. Rats were then divided into five groups: Control, PCL-GE, PCL-GE-SHED, PLGA-BG, and PLGA-BG-SHED, and received corresponding composite scaffolds with/without SHED at the extraction site. Tissue samples were collected at 2, 3, and 6 months post-implantation (4 rats per group). Gross and histological analyses were conducted to assess osteoid or bone formation. Immunohistochemistry for osteocalcin and human mitochondria was performed to evaluate bone components and human stem cell viability in the tissue. ResultsBone tissue formation was observed in the PCL-GE and PLGA-BG groups compared to the control, where no bone formation occurred. PLGA-BG scaffolds demonstrated greater bone regeneration potential than PCL-GE over 2–6 months. Additionally, scaffolds with SHED accelerated bone formation compared to scaffolds alone. Osteocalcin expression was detected in all rats, and positive immunoreactivity for human mitochondria was observed in the regenerated bone tissue with PCL-GE-SHED and PLGA-BG-SHED. ConclusionPCL-GE and PLGA-BG composite scaffolds effectively repaired and regenerated bone tissue in rat cleft palate defects. Moreover, scaffolds supplemented with SHED exhibited enhanced osteogenic potency. Clinical significancePCL-GE and PLGA-BG scaffolds, augmented with SHED, emerge as promising biomaterial candidates for addressing cleft repair and advancing bone tissue engineering endeavors.

Gelatin and lipidoid integrate to create gelasomes to enhance siRNA delivery with low toxicity

RNAi therapeutics possess the potential to cure many uncurable human diseases. For instance, RNAi therapeutics using liposomes showed remarkable survival benefits in patients with liver diseases. However, the extension of liposomes to deliver RNA to cure other ailments has largely been unsuccessful. Therefore, researchers are focusing on designing and testing different combinations of materials for versatile RNA delivery applications. Yet, an efficient and safe RNA delivery platform has not been identified. In this work, we have developed a new class of RNA-delivery vehicle called “Gelasomes,” using an incongruous combination of gelatin and lipidoid to exploit each material's unique properties while overcoming their inherent limitations. The low in vivo toxicity of Gelasomes is attributed to the exterior gelatin layers that shield the exposure of cationic lipidoid-siRNA clusters and yet present a biocompatible surface. Indeed, toxicity studies in mice indicate that repeated administration of Gelasomes (up to 48 mg/kg BW) is well-tolerated with no notable changes in body weight, hematology, or serum chemistry. Interestingly, the gelatin outer layer efficiently protects siRNA from serum degradation (48 h), preserving its functionality beyond two months of storage. Notably, Gelasomes possess dual siRNA conjugation modes, i.e., electrostatic binding with lipidoid core and covalent attachment to gelatin surface. The bivalency coupled with lipidoids' high transfection efficiency rendered Gelasomes with remarkably high gene silencing efficiency (>90 %) at very low treatment doses in vitro (40 μg/mL). In vivo studies further confirmed the high gene silencing ability of Gelasomes in non-small cell lung tumor mouse models. This new platform is tunable on all fronts: size, degree of surface coating, and biomolecule functionalization. Truncating the lipidoid C14-tail to a C8-tail yielded Gelasomes of reduced size. As lipidoids with different carbon lengths are synthesizable, we can develop a library of Gelasomes with different sizes. The surface coating with less gelatin resulted in high transfection efficiency at low doses of Gelasomes. The structure of Gelasomes offers chemical handles to couple target-specific molecules like antibodies to tune their properties for efficient biological application.

Eco-friendly triboelectric nanogenerator for self-powering stacked In2O3 nanosheets/PPy nanoparticles-based NO2 gas sensor

As atmospheric issues and energy crises worsen, developing environmentally friendly, low-cost, high-performance self-powered gas sensing systems for gas pollutant monitoring is crucial for the development of ecological civilization. In this work, an eco-friendly self-powered nitrogen dioxide (NO2) sensor (EFNS) system based on an eco-friendly triboelectric nanogenerator (EF-TENG) is reported. The system comprises a power supply unit (EF-TENG) and a sensing unit (In2O3/PPy sensor), connected through a signal stabilization circuit. EF-TENG utilizes eco-friendly and biodegradable gelatin and PLA/PBAT as the friction layer. By introducing leaf structures on the gelatin surface using a template method, the output voltage and current of EF-TENG were increased by 1.44 and 1.67 times, respectively. The peak power density and root mean square power density of EF-TENG reached 1386 mW m−2 and 185.35 mW m−2, respectively. Additionally, EF-TENG exhibited excellent long-term stability, maintaining a stable output voltage (∼24 V) after rectification and voltage stabilization treatment under conditions of 15–55°C and 40–80 % RH. Additionally, an In2O3/PPy heterostructure sensor was prepared, and the EFNS system was constructed through impedance matching effects, revealing the NO2 response mechanism of the In2O3/PPy heterostructure. This achieved a wide detection range and highly sensitive (Vg/Va = 355 %@30 ppm) detection of NO2. This work provides insights into eco-friendly self-powered gas sensors and sensing mechanisms, offering ideas for the development of environmental monitoring sensors and clean energy harvesting devices.

Development of Hybrid Electrospun Nanofibers: Improving Effects of Cellulose Nanofibers (CNFs) on Electrospinnability of Gelatin.

Cellulose nanofibers (CNFs) were used to improve the electrospinnability of the gelatin protein in a water/ethanol/acetic acid (3:2:3, v/v) solution. The effects of different concentrations of CNFs (0.5-4%) on the important physical properties of the gelatin solution (15%), including rheology, conductivity, and surface tension, were investigated. The apparent viscosity and shear-thinning behavior were increased by increasing the CNF concentration from 0 to 4% at a low shear rate (<10 s-1). CNFs also increased the electrical conductivity and surface tension of the gelatin solution. Scanning electron microscopy (SEM) images revealed uniformly ordered structures with good continuity without fracture or bead formation in all hybrid nanofibers. They also showed that the average diameters of fibers decreased from 216 nm in the pure gelatin nanofibers to 175.39 nm in the hybrid gelatin/CNF (4%) ones. Differential scanning calorimetry (DSC) results showed that CNFs increased Tg, and X-ray diffraction (XRD) analysis showed that the electrospinning process caused the formation of more amorphous structures in the gelatin/CNF hybrid nanofibers. The tensile test indicated that by adding 2% CNFs, the ultimate tensile strength (UTS) and strain at break (SB) of nanofiber mats increased from 4.26 to 10.5 MPa and 3.3% to 6.25%, respectively. The current study indicated that incorporating CNFs at the optimal concentration into a gelatin solution can improve the resulting hybrid nanofibers' morphology, average diameter, and mechanical properties.

Implantable Wet‐Adhesive Flexible Electronics with Ultrathin Gelatin Film

AbstractImplantable flexible electronic has attracted significant research interest in various fields. However, it still faces the challenge of simultaneously achieving tight adhesion to tissues in a mildly wet environment and possessing excellent biocompatibility to reduce immune rejection reactions after implantation. Here, a degradable wet‐adhesive flexible electronic device based on liquid metal and ultrathin gelatin film is developed. The ultrathin gelatin film forms numerous hydrogen bonds with tissue in a slightly humid environment, rapidly constructing a wet‐adhesive interface without damaging tissue structure. Inkjet printing is utilized to pattern the mixture of liquid metal and PVP on the surface of the ultrathin gelatin to create flexible patch. With the excellent conductivity of liquid metal, low toxicity, and similarity to natural tissue components of gelatin, flexible patch exhibits outstanding biocompatibility and fatigue resistance. It can be implanted in the body for up to 6 weeks, retaining monitoring capabilities and resisting 1 000 000 cycles of bending fatigue. This study provides a novel strategy for the future development of implantable flexible electronics.

Evaluation of Gelatin/Hyaluronic Acid-Generated Bridging in a 3D-Printed Titanium Cage for Bone Regeneration.

3D-printed titanium (Ti) cages present an attractive alternative for addressing issues related to osteoporosis-induced fractures, accidental fractures, and spinal fusion surgery due to disc herniation. These Ti-based bone implants possess superior strength compared to other metals, allowing for versatile applications in orthopedic scenarios. However, when used as standalone solutions, certain considerations may arise, such as interaction with soft tissues. Therefore, to overcome these issues, the combination with hydrogel has been considered. In this study, to impart Ti with regenerative abilities a 3D-printed Ti cage was loaded with gelatin and hyaluronic acid (G-H) to improve the cell attachment ability of the Ti-based bone implants. The void spaces within the mesh structure of the 3D Ti cage were filled with G-H, creating a network of micro-sized pores. The filled G-H acted as the bridge for the cells to migrate toward the large inner pores of the 3D Ti cage. Due to the microporous surface and slow release of gelatin and hyaluronic acid, the biocompatibility of the coated Ti cage was increased with an elevation in osteoconduction as depicted by the up-regulation of bone-related gene expressions. The in vivo implantation in the rabbit femur model showed enhanced bone regeneration due to the coated G-H on the Ti cage compared to the pristine hollow Ti cage. The G-H filled the large holes of the 3D Ti cage that acted as a bridge for the cells to travel inside the implant and aided in the fast regeneration of bone.

Flagellin is essential for initial attachment to mucosal surfaces by Clostridioides difficile.

Mucins are glycoproteins which can be found in host cell membranes and as a gelatinous surface formed from secreted mucins. Mucosal surfaces in mammals form a barrier to invasive microbes, particularly bacteria, but are a point of attachment for others. Clostridioides difficile is an anaerobic bacterium, which colonizes the mammalian gastrointestinal (GI) tract and is a common cause of acute GI inflammation leading to a variety of negative outcomes. Although C. difficile toxicity stems from secreted toxins, colonization is a prerequisite for C. difficile disease. While C. difficile is known to associate with the mucous layer and underlying epithelium, the mechanisms underlying these interactions that facilitate colonization are less well understood. To understand the molecular mechanisms by which C. difficile interacts with mucins, we used ex vivo mucosal surfaces to test the ability of C. difficile to bind to mucins from different mammalian tissues. We found significant differences in C. difficile adhesion based upon the source of mucins, with highest levels of binding observed to mucins purified from the human colonic adenocarcinoma line LS174T and lowest levels of binding to porcine gastric mucin. We also observed defects in adhesion by mutants deficient in flagella but not type IV pili. These results imply that interactions between host mucins and C. difficile flagella facilitate the initial host attachment of C. difficile to host cells and secreted mucus. Importance Clostridioides difficile is one of the leading causes of hospital-acquired infections worldwide and presents challenges in treatment due to recurrent gastrointestinal disease after treatment with antimicrobials. The mechanisms by which C. difficile colonizes the gut represent a key gap in knowledge, including its association with host cells and mucosa. Our results show the importance of flagellin for specific adhesion to mucosal hydrogels and can help to explain prior observations of adhesive defects in flagellin and pilin mutants.

A Novel Robust Method Mimicking Human Substratum To Dissect the Heterogeneity of Candida auris Biofilm Formation.

Candida auris is a pathogen of urgent threat level as marked by the CDC. The formation of biofilms is an essential property of this fungus to establish infection and escape drug treatment. However, our understanding of pathogenesis through biofilm is hampered by heterogeneity in C. auris biofilms observed in different studies. It is imperative to replicate in vivo conditions for studying C. auris biofilm formation in vitro. Different methods are standardized, but the surface used to form biofilms lacks consistency as well as the architecture of a typical biofilm. Here, we report an in vitro technique to grow C. auris biofilms on gelatin-coated coverslips. Interestingly, C. auris cells grown on gelatin-coated coverslips either on modified synthetic sweat media or RPMI 1640 resulted in similar multilayer biofilm formation with extracellular polymeric substances (EPS). This method is also consistent with the biofilm formation of other Candida species, such as Candida glabrata and Candida albicans. Biofilms of C. glabrata developed through this method show pseudohyphae and EPS. This method can be used to understand the molecular basis of biofilm formation, associated pathogenesis, and drug tolerance. The technique is cost-effective and would thus serve in rightful screening and repurposing drug libraries for designing new therapeutics against the less-studied high-alarm pathogen C. auris. IMPORTANCE Heterogeneity is seen when multidrug-resistant C. auris biofilm is cultured using different reported methods. Biofilm formed on the gelatin surface mimics the condition of a host environment that has multilayers and EPS. This method has feasibility for drug screening and analyzing biofilms through three-dimensional (3D) reconstruction. This in vitro biofilm formation technique is also exploited to study the formation of biofilm of other Candida species. The biofilms of C. glabrata and C. albicans can also be correctly mimicked using gelatin in the biofilm-forming environment. Thus, the novel in vitro method for biofilm formation reported here can be widely used to understand the mechanism of biofilm formation, related virulence properties, and drug tolerance of C. auris and other Candida species. This simple and low-cost technique is highly suitable for screening novel inhibitors and repurposed libraries and to design new therapeutics against Candida species.

A composite hydrogel membrane with shape and water retention for corneal tissue engineering

Tissue engineering (TE) cornea is one of the most potential alternatives to the shortage of corneal donors in cornea transplantation. Sodium alginate (SA) hydrogel is commonly used as scaffold in TE. Herein, we present an approach to construct a composite hydrogel, which with SA fiber skeleton structure for shape retention and gelatin surface modification for water retention. The light transmittance, water retention rate, and swelling rate of hydrogels were characterized, and the tensile mechanical properties were also investigated. Keratinocytes were treated with material extract liquor and the results showed that the gelatin modified SA hydrogel has good cytocompatibility. Furthermore, human corneal stromal fibroblasts (HCSFs) from the lenticules were implanted on the surface of gels, and the SA-gelatin hydrogel significantly improved the adhesion and spreading of HCSFs. Finally, we discussed the improvement and application prospect of the composite hydrogel as cornea equivalents.

Effect of different types of nanocellulose on the structure and properties of gelatin films

The use of nanocellulose to enhance the performance of biopolymer films is a recent trend in food packaging. This current study aims to investigate the impact of incorporating different morphologies of nanocellulose, namely cellulose nanofibrils (CNFs), cellulose nanospheres (CNSs), and cellulose nanocrystals (CNCs), on the structures and properties of gelatin film. The FTIR confirmed the formation of triple helix structures among CNF and CNC groups due to more hydrogen bonds generated between cellulose and gelatin molecules compared to CNSs. SEM analysis revealed a uniform distribution of CNCs in gelatin but aggregated with an increase in CNC contents, while CNF and CNS groups exhibited aggregation of cellulose upon the surface of gelatin because the vast surface area of nanospheres along with the nanofibrils structure led to irregular dispersion of cellulose (especially CNSs). In comparison to the CNF5% and CNS groups, CNC and CNF2% (w/w) groups greatly improved the mechanical characteristics of the gelatin films to 131.27% EAB and 20.71 MPa TS due to strong hydrogen bond interaction, more triple helix structures, and the relatively thorough dispersion of cellulose in the gelatin film. The incorporation of nanocellulose reduced the solubility and transparency of the gelatin films. Of all the films, CNC2% film exhibited a significant reduction of water vapor permeability due to the facile and even dispersion of CNCs in the gelatin network structure. Adding nanocellulose had little impact on the gelatin films’ heat stability. Therefore, the current work may be a new viable strategy for the construction of a novel molecular network system for enhancing the effectiveness of gelatin film containing lower content of CNCs.

Nanoscale level gelatin-based scaffolds enhance colony formation of porcine testicular germ cells.

The extracellular matrix is important in cell growth, proliferation, and differentiation. Gelatin, a support for adhering cells, is used for coating culture plate surfaces of several primary and stem cells. However, gelatin characteristics on culture plates and its cell interactions are not understood. Here, we aimed to identify the effect of gelatin topography on culture plates on the proliferation and colony formation of porcine spermatogonial germ cells (pSGC). To generate different surface topographies, gelatin powder was dissolved in H2O at varying melting temperatures (40, 60, 80, and 120°C) and coated on the surface of the culture plates. At 40°C, the pores of the gelatin scaffold were regular ellipses 5-6μm in diameter and 10-30nm in thickness. However, at 120°C, irregular pores 20-30μm in diameter and 10-20nm in thickness were obtained. Additionally, the number of attached cells and pSGC colonies were significantly more at 40°C than at 120°C after a week of culture. Interestingly, the feeder cells did not settle properly at 120°C but detached easily from the culture dishes. PSGC colonies were 100μm in diameter at 40°C, with small and detached colonies observed at 120°C. Thus, optimal topography of gelatin was obtained at 40°C, which was sufficient for the proliferation of feeder cells and the formation of pSGC colonies. Thus, gelatin scaffold conditions at 40°C and 60°C were optimal for the derivation and culture of pSGC, and gelatin surface morphology is important for the maintenance of supportive feeder cells for pSGC proliferation and colony formation.

Gum, sap and canker-colloid carcinoma -pancreas

Colloid carcinoma pancreas is an infiltrative ductal epithelial neoplasm of the pancreas characteristically denominating a preponderant (&gt; 80%) component of enlarged pools of extracellular stromal mucin pervaded with suspended neoplastic cells. Colloid carcinoma pancreas is a microsatellite stable tumefaction and exhibits KRAS genetic mutation confined to codon 12. Tumefaction is posited to arise from the inverse polarization of cells with stromal mucin glycoproteins facing the intrinsic cellular surface. Cogent clinical symptoms such as abdominal or epigastric pain, pancreatitis, diarrhoea, hyperbilirubinemia or loss of weight are discerned. Tumefaction emerges as an enlarged, well-demarcated lesion with a mean diameter of 5 centimetres and a solid, firm, gelatinous cut surface. Neoplasm is predominantly comprised of enlarged, extracellular accumulates of stromal mucin with minimal carcinoma cells suspended within extra-cellular mucin pools. Cuboidal or columnar epithelial cells configure cribriform or stellate cellular clusters or miniature tubules and strips of columnar cells along with signet ring cells.

Fabrication, optimization and cytotoxicity assessment of Ganoderma lucidum Triterpenoid-loaded electrospun gelatin nanofiber membrane as potential skin patch

Ganoderma lucidum triterpenoids (GLT) have shown special anti-tumor effects, but due to low yields and their hydrophobic structure, they have not found much clinical application. Box Behnken Design (BBD) developed a formulation to optimize the effective parameters in encapsulating GLT. Then, Gelatin nanofibers were characterized by SEM, 1H-NMR, and FTIR. Finally, the GLT release kinetics and GLT nanofibers cytotoxicity was studied. BBD shows the best values obtained are the solvent ratio of 11.5%, gelatin concentration of 22%, and voltage of 20 kV which were validated by an experimental assay. The results showed that the positively charged ionic groups present on the surface of gelatin adsorbed the carboxyl groups in GLT and the magnetic fields created by their nucleus influenced each other. Finally, GLT nanofibers with an average size distribution of 75.4 nm were observed. The result showed an efficiency of 75% for drug entrapment. The release kinetics demonstrated a sustained release of GLT follows the Korsmeyer-Peppas model that suggests a combination of surface drug dissolution and quasi-Fickian diffusion. Also, GLT nanofibers showed a higher cytotoxic activity against MCF-7 cell lines than free GLT. The generated model suggests a new approach to prediction and experimental nanofibers.

305 Enhancing Endothelialization of Flow Diverting Stents: An In Vitro Study

INTRODUCTION: Flow diverting (FD) stents revolutionized the management of broad neck aneurysms. Several FD stents surface modifications have been developed over the last decade to reduce thromboembolic complications or enhance aneurysmal occlusion rates. Promoting FD endothelization through surface coating has emerged as a novel modality to enhance stent coverage, thus improving aneurysmal occlusion, reducing aneurysmal progression and post-treatment failure. Herein, we report our in vitro experience with FD surface modification using gelatin. METHODS: PED Flex stents were incubated overnight with either PBS (unmodified) or gelatin, followed by a three-hour incubation with human microvascular endothelial cells. Endothelial cell attachment and proliferation were assessed at various time points. RESULTS: There was a significant increase(p &lt; 0.05) in endothelial cell attachment on gelatin(6.3 ± 2.1)surface modified stents compared to unmodified control stents. This increase in endothelial cells was maintained 14 days gelatin 6.3 ± 2.7, fold of control)following cell incubation but gradually decreased until it became insignificant by day 21. Next, we analyzed the temporal rate of endothelial stent coverage. Following cell incubation, 20% of surface-modified stents were coated by endothelial cells on day 5 compared to just 2% in unmodified stents. This difference in cell coverage remained significant (p &lt; 0.05), with surface-modified stents being entirely covered by 2 weeks while unmodified stents were only 50% covered. We also observed a significant increase (p &lt; 0.05, fold of unmodified) in endothelial cell migration onto (1.8 ± 0.2) and from (1.5 ± 0.033) gelatin-coated stents compared to unmodified controls. CONCLUSIONS: Our in vitro experience demonstrates that gelatin has the potential to enhance the endothelialization of FD, leading to increased aneurysm occlusion rates, thereby minimizing post-treatment failure. Further investigations are essential to fully evaluate this novel modality and compare it to the commercially available devices.

Gelatin-based anticancer drug delivery nanosystems: A mini review.

Drug delivery nanosystems (DDnS) is widely developed recently. Gelatin is a high-potential biomaterial originated from natural resources for anticancer DDnS, which can effectively improve the utilization of anticancer drugs and reduce side effects. The hydrophilic, amphoteric behavior and sol-gel transition of gelatin can be used to fulfill various requirements of anticancer DDnS. Additionally, the high number of multifunctional groups on the surface of gelatin provides the possibility of crosslinking and further modifications. In this review, we focus on the properties of gelatin and briefly elaborate the correlation between the properties and anticancer DDnS. Furthermore, we discuss the applications of gelatin-based DDnS in various cancer treatments. Overall, we have summarized the excellent properties of gelatin and correlated with DDnS to provide a manual for the design of gelatin-based materials for DDnS.

O/W/O multiple emulsions containing soluble collagen: in vitro and in vivo skin biophysical properties evaluation

The integrity of the stratum corneum is essential for skin hydration. In order to fulfill all of its functions, a balance of the water content in the stratum corneum is necessary, as well as maintaining the epidermis, an essential objective of cosmetic formulations. Cosmetic skin hydration can be achieved through the frequent application of cosmetic products that can act through basic mechanisms: occlusion, moisturization, and hydration or active moisturization. Therefore, when developing new cosmetic products, it is important to consider their positive effect on skin hydration and viscoelasticity, considering that the objective of a cosmetic product is to protect the skin and delay skin aging. Subsequently, multiple O/W/O emulsions were developed and skin hydration was evaluated in vitro and in vivo. The in vitro method for skin hydration employs gelatin whose composition mimics collagen and NMF of the skin, forming a surface (1 cm thick) through which internal water vapor can be released. The occlusion provided to this gelatin surface is evaluated, and the hydrating power of the applied products is determined. Due to the composition of the gelatin support cell and the evaporation of water inside it, it can simulate TEWL of the skin. The in vivo evaluation of hydration, pH, and sebum of the aqueous solution of proteins, simple O/W, and multiple O/W/O with collagen showed that O/W/O emulsions provided greater occlusive and oily content, maintaining the pH levels of the skin. Therefore, these O/W/O systems improve conditions for dry skin.