Hydroxyethylcellulose Gel Research Articles

The Wound-Healing Effect of a Novel Fibroblasts-Impregnated Hydroxyethylcellulose Gel in a Rat Full-Thickness Burn Model: A Preclinical Study.

Background/Objectives: The objective of this study was to assess the efficacy of a cell-containing wound dressing based on fibroblasts in hydroxyethylcellulose (HEC) gel for the local treatment of deep partial-thickness and/or full-thickness skin burns in an animal model. Methods: The rats (male Wistar, n = 100) were subjected to a full-thickness thermal burn (16 cm2). Radical necrectomy was performed one day after the burn. Three days later, the rats were randomly assigned to one of four groups: group 1 (no treatment), group 2 (chloramphenicol and methyluracil ointment, a routine clinical treatment), group 3 (a gel without cells, mock treatment), and group 4 (a dermal fibroblast-impregnated HEC gel). The treatment lasted for five days. The wound-healing process was evaluated by planimetric, cytologic, histologic, and immunohistochemical methods. Results: The differences in the rate of wound healing and the characteristics of wound cytology were identified. In the group 4, a regenerative type of cytogram was revealed, characterized by a significantly increased number of fibroblastic cells in comparison to samples from non-treated and mock-treated animals. Biopsy samples of burn wounds from animals in the group 4l demonstrated the presence of mature granulation tissue and a large number of microvessels. The repair process was stimulated, as evidenced by the increased thickness of newly formed granulation tissue and epidermis in the wound zone, elevated cellularity, and enhanced re-epithelialization activity. The number of Ki-67-positive proliferating cells was significantly higher in group 4 than in the control groups). A small number of non-proliferating donor fibroblasts was observed in the wound area 3 days after the end of treatment. Conclusions: The cell product is an effective agent for promoting wound healing during the regenerative phase. The experiments demonstrated that a gel populated by dermal fibroblasts can stimulate reparative regeneration processes in deep partial- and full-thickness burn wounds.

Burn Wound Healing Activity of Hydroxyethylcellulose Gels with Different Water Extracts Obtained from Various Medicinal Plants in Pseudomonas aeruginosa-Infected Rabbits.

Burn injuries represent a significant problem in clinical practice due to the high risk of infection and the prolonged healing process. Recently, more attention has been given to natural remedies such as water extracts of various medicinal plants, which possess anti-inflammatory and wound healing properties. The aim of this study is to evaluate the efficacy and safety of Satureja montana L. and other water extracts in a burn wound model. The study involved male Californian rabbits (n = 52) divided into eight groups. Burn wounds were modeled on the animals and subsequently treated with gels based on Satureja montana L. and other water extracts. The reparative potential of the epidermis (assessed by Ki-67 expression), the state of local immunity (measured by the number of CD-45 cells), and the anti-inflammatory role of mast cells (measured by tryptase levels) were evaluated. Bacteriological and morphological studies were conducted. The most pronounced bactericidal, reparative, and immunostimulatory effects were observed after the treatment using a gel mixture of water extracts from Satureja montana L., Salvia sclarea, Coriandrum sativum L., and Lavandula angustifolia in equal proportions (1:1:1:1). The other gels also demonstrated high efficacy in treating burn wounds, especially when using a strain of Pseudomonas aeruginosa resistant to several antibiotics. Immunohistochemical studies showed a significant increase in the number of Ki-67-positive cells in the basal layer of the epidermis and a decrease in the number of CD-45-positive cells, indicating improved proliferative activity and reduced inflammation. This study confirms the hypothesis that the use of water extract mixtures significantly enhances the reparative potential, improves the immune response in the treatment of burns, and promotes wound healing. These findings pave the way for further research and the application of complex phytotherapeutic agents, specifically water extracts of medicinal plants containing phenols and antioxidants in burn wound therapy.

Development of novel antimicrobials with engineered endolysin LysECD7-SMAP to combat Gram-negative bacterial infections

BackgroundAmong the non-traditional antibacterial agents in development, only a few targets critical Gram-negative bacteria such as carbapenem-resistant Pseudomonas aeruginosa, Acinetobacter baumannii or cephalosporin-resistant Enterobacteriaceae. Endolysins and their genetically modified versions meet the World Health Organization criteria for innovation, have a novel mode of antibacterial action, no known bacterial cross-resistance, and are being intensively studied for application against Gram-negative pathogens.MethodsThe study presents a multidisciplinary approach, including genetic engineering of LysECD7-SMAP and production of recombinant endolysin, its analysis by crystal structure solution following molecular dynamics simulations and evaluation of antibacterial properties. Two types of antimicrobial dosage forms were formulated, resulting in lyophilized powder for injection and hydroxyethylcellulose gel for topical administration. Their efficacy was estimated in the treatment of sepsis, and pneumonia models in BALB/c mice, diabetes-associated wound infection in the leptin receptor-deficient db/db mice and infected burn wounds in rats.ResultsIn this work, we investigate the application strategies of the engineered endolysin LysECD7-SMAP and its dosage forms evaluated in preclinical studies. The catalytic domain of the enzyme shares the conserved structure of endopeptidases containing a putative antimicrobial peptide at the C-terminus of polypeptide chain. The activity of endolysins has been demonstrated against a range of pathogens, such as Klebsiella pneumoniae, A. baumannii, P. aeruginosa, Staphylococcus haemolyticus, Achromobacter spp, Burkholderia cepacia complex and Haemophylus influenzae, including those with multidrug resistance. The efficacy of candidate dosage forms has been confirmed in in vivo studies. Some aspects of the interaction of LysECD7-SMAP with cell wall molecular targets are also discussed.ConclusionsOur studies demonstrate the potential of LysECD7-SMAP therapeutics for the systemic or topical treatment of infectious diseases caused by susceptible Gram-negative bacterial species and are critical to proceed LysECD7-SMAP-based antimicrobials trials to advanced stages.

Investigating Bioactive-Glass-Infused Gels for Enamel Remineralization: An In Vitro Study.

Dental hypersensitivity remains widespread, underscoring the need for materials that can effectively seal dental tubules. This study evaluated the potential of bioactive-glass-infused hydroxyethyl cellulose gels in this context. Five gels were synthesized, each containing 20% bioactive glass (specifically, 45S5, S53P4, Biomin F, and Biomin C), with an additional blank gel serving as a control. Subjected to two months of accelerated aging at 37 ± 2 °C, these gels were assessed for key properties: viscosity, water disintegration time, pH level, consistency, adhesion to glass, and element release capability. Across the board, the gels facilitated the release of calcium, phosphate, and silicon ions, raising the pH from 9.00 ± 0.10 to 9.7 ± 0.0-a range conducive to remineralization. Dissolution in water occurred within 30-50 min post-application. Viscosity readings showed variability, with 45S5 reaching 6337 ± 24 mPa/s and Biomin F at 3269 ± 18 mPa/s after two months. Initial adhesion for the blank gel was measured at 0.27 ± 0.04 Pa, increasing to 0.73 ± 0.06 Pa for the others over time. Gels can release elements upon contact with water (Ca- Biomin C 104.8 ± 15.7 mg/L; Na- Biomin F 76.30 ± 11.44 mg/L; P- Biomin C 2.623 ± 0.393 mg/L; Si- 45S5-45.15 ± 6.77mg/L, F- Biomin F- 3.256 ± 0.651mg/L; Cl- Biomin C 135.5 ± 20.3 mg/L after 45 min). These findings highlight the gels' capacity to kickstart the remineralization process by delivering critical ions needed for enamel layer reconstruction. Further exploration in more dynamic, real-world conditions is recommended to fully ascertain their practical utility.

Preparation and efficacy verification of three-dimensional printed partitioned multi-effect precision-care gel facial mask.

A partition multi-effect precision-care gel facial mask conforming to facial skin characteristics was prepared using three-dimensional (3D) printing technology. First, the hydrogel matrix and humectant of a 3D-printed gel for facial masks were screened, and three 3D-printed gels of arbutin, hexapeptide, and salicylic acid were prepared with whitening, wrinkle removal, and oil control functions, respectively. Skin irritation tests were performed on the gels. Physicochemical properties such as pH, heat and cold tolerance were evaluated. The efficacy of three 3D-printed gels was assessed by measuring melanin value, wrinkle depression score, and oil secretion. Finally, the facial mask model design and printing parameters were studied, and a partition multi-effect precision-care gel facial mask was printed in line with facial skin characteristics. For the 3D-printed facial mask, the gel prescription with 2% hydroxyethyl cellulose gel as matrix and 7% glycerol as humectant was the best. The prepared 3D-printed gel did not irritate the human skin, and its physicochemical properties met the Chinese facial mask industry standard (QB/T2872-2017). We showed that three types of 3D-printed gels containing arbutin, hexapeptide, and salicylic acid could be applied to the corresponding parts of the face to solve different problems, such as facial skin dullness, wrinkles, and oil secretion. Therefore, according to facial physiological characteristics, the facial mask model was designed for the forehead and nasolabial fold, which needs to be anti-wrinkled; the cheek, which needs to be whitened; and the nose and chin, which need oil control. The optimal printing parameters were 0.26 mm nozzle diameter, 90 mm/s printing speed, 30% filling density, 140% wire extrusion ratio, and 0.25 mm layer height. Different skin care effects can be achieved using a three-nozzle printer to print arbutin, hexapeptide, or salicylic acid gel on the mask's forehead and nasolabial fold, cheek, and nose and chin, respectively. The 3D-printed partition multi-effect care gel facial mask prepared according to the skin features of different parts of the face can overcome the problem of the single skincare effect of the mass-produced facial masks.

A workflow for predicting radiofrequency-induced heating around bilateral deep brain stimulation electrodes in MRI.

Heating around deep brain stimulation (DBS) in magnetic resonance imaging (MRI) occurs when the time-varying electromagnetic (EM) fields induce currents in the electrodes which can generate heat and potentially cause tissue damage. Predicting the heating around the electrode contacts is important to ensure the safety of patients with DBS implants undergoing an MRI scan. We previously proposed a workflow to predict heating around DBS contacts and introduced a parameter, equivalent transimpedance, that is independent of electrode trajectories, termination, and radiofrequency (RF) excitations. The workflow performance was validated in a unilateral DBS system. To predict RF heating around the contacts of bilateral (DBS) electrodes during an MRI scan in an anthropomorphic head phantom. Bilateral electrodes were fixed in a skull phantom filled with hydroxyethyl cellulose (HEC) gel. The electrode shafts were suspended extracranially, in a head and torso phantom filled with the same gel material. The current induced on the electrode shaft was experimentally measured using an MR-based technique 3cm above the tip. A transimpedance value determined in a previous offline calibration was used to scale the shaft current and calculate the contact voltage. The voltage was assigned as a boundary condition on the electrical contacts of the electrode in a quasi-static (EM) simulation. The resulting specific absorption rate (SAR) distribution became the input for a transient thermal simulation and was used to predict the heating around the contacts. RF heating experiments were performed for eight different lead trajectories using circularly polarized (CP) excitation and two linear excitations for one trajectory. The measured temperatures for all experiments were compared with the simulated temperatures and the root-mean-squared errors (RMSE) were calculated. The RF heating around the contacts of both bilateral electrodes was predicted with ≤ 0.29°C of RMSE for 20 heating scenarios. The workflow successfully predicted the heating for different bilateral DBS trajectories and excitation patterns in an anthropomorphic head phantom.

Research by choice of excipients ingredients of the gel for the therapy of radiation lesions of the skin based on rheological studies

The aim of this work is to conduct a research analysis of changes in the structural and mechanical properties of the gel from the addition of active substances and surfactants.
 Materials and methods. In the presented work, model samples of the gel with active substances were studied: freshly obtained stonecrop juice, sea buckthorn oil, rosehip oil, St. John's wort oil and quercetin. As substances for the manufacture of bases hydrocolloids of cellulose derivatives were used: sodium carboxymethylcellulose (NaCMC) and hydroxyethylcellulose (HEC) with a surfactant Lanette SX.
 A study of the rheological properties of the samples was performed using a rheoviscometer Rheolab QC (Anton Paar, Austria) using a system of coaxial cylinders C-CC27 / SS. The Rheolab QC rheometer is equipped with RheoPlus software, which allows you to set the necessary experimental conditions (shear rate gradient range, number of measuring points and measurement time of one point).
 Results. The rheological properties of model samples of NaCMC and HEC gels, depending on the used concentration, were studied. With increasing concentrations of both NaCMC and HEC thixotropy of dispersed systems decreases. The change of structural and mechanical parameters of hydrogels from the addition of active ingredients and surfactant is analyzed, and established that adding them into the hydrogels increases the structural and mechanical parameters of model samples.
 A study of gels with a constant concentration of sodium carboxymethylcellulose and hydroxyethylcellulose and different content of surfactant Lanette SX established that as the surfactant concentration increases, the area of the hysteresis loop and the resistance of the dispersed system to the applied mechanical fracture increase.
 Conclusions. According to the results of the obtained structural and mechanical parameters and rheograms of the studied model samples of gels, it is rational to use in further studies of sodium carboxymethyl-cellulose (1.5 %) and hydroxyethylcellulose (1.25 %) stabilized Lannete SX in concentrations of 4-5 % and 3-5 % respectively

The effectiveness of obstetric gel application in shortening labor duration and preserving vaginal perineal integrity: prospective observational study

Aim: The aim of this study to determine the effects of obstetric gel application on labor outcomes.
 Materials and Method: This nonrandomized controlled study was carried out between January 2019 and June 2019 in a tertiary-care hospital. Nulliparous pregnant women with low risk, vertex position, between the ages of 16-40 years, with an estimated fetal weight of 2500-4000 grams and a gestational week between 37-41 weeks were included in the study. Using an applicator, 3-5 ml of a hydroxyethyl cellulose gel was applied to the vaginal canal of the study group (n=142) at the first stage of labor (before 5 cm cervical opening). The procedure was repeated every two hours until the birth of the baby. The control group (n=191) received standard antenatal care. 
 Results: The need for episiotomy was significantly lower in the study group compared to the control group (n=72 (50.7%) vs. n=175 (91.6%)) (Z=18.902, p

The Effect of Local Melatonin Application Following the Removal of an Impacted Mandibular Third Molar

Pain, swelling, limitation of the mouth opening, development of intra-bony defects, and bone loss are common side effects of removing the impacted third molar. The purpose of this study was to measure the association of applying melatonin in the socket of an impacted mandibular third molar with osteogenic activity and the anti-inflammatory effects. This prospective, randomized, blinded trial comprised of patients who required removal of the impacted mandibular third molar. The patients were divided into two groups (n=19) as follows: melatonin group (3mg of melatonin into 2ml of 2% hydroxyethyl cellulose gel was packed into the socket) and placebo group (2ml of 2% hydroxyethyl cellulose gel was placed in the socket). The primary outcome was bone density, measured using Hounsfield unit immediately after surgery and 6months later. Secondary outcome variables included serum osteoprotegerin level (Ng/ml) that measured immediately, 4weeks and 6months postoperatively. Other clinical outcome measures were pain by visual analog scale, maximum mouth opening (MMO) (millimeter), and swelling (millimeter) that were evaluated immediately, 1, 3, and 7days postoperatively. The data were analyzed by independent t-test of Wilcoxon's rank-sum, analysis of variance, and generalized estimating equation (P≤.05). Thirty-eight patients (25 female and 13 males) with a median age of 27years were enrolled in the study. There was no statistical significance in bone density observed in both groups [melatonin group: 978.5(951.3-1015.8), control group: 965.8 (924.6-998.7), P=.1]. Alternatively, there were statistically significant improvements in osteoprotegerin levels (on week 4), MMO (on day1), and swelling (on day 3) in the melatonin group compared to those in the placebo group [1.9(1.4-2.4), 39.68±1.35, and 14.36±0.80 versus 1.5(1.2-1.4); 38.33±1.20, and 14.88±0.59; P=.02, .003, 0.031, respectively]. The pain values showed statistically significant improvement throughout the follow-up period in the melatonin group compared to the placebo group [5(3-8), 2(1-5), and 0(0-2) versus 7(6-8), 5(4-6), and 2(1-3); P<.001, respectively]. The results support the anti-inflammatory effect of melatonin in reducing the pain scale and swelling. Furthermore, it plays a role in the improvement of MMO. On the other hand, the osteogenic activity of melatonin could not be detected.

Dermal Delivery of Korean Red Ginseng Extract: Impact on Storage Stability of Different Carrier Systems and Evaluation of Rg1 and Rb1 Skin Permeation Ex Vivo.

The root extract of Panax ginseng C.A. Meyer (Korean red ginseng/KRG extract) is a traditional Asian remedy introduced to dermal products for its antioxidative potential. However, little is known about technological aspects or skin penetration of main ginsenosides. Thus, stable oil-in-water nanoemulsions (NEs) and hydrogels for dermal delivery of KRG extract were developed and characterised using light scattering methods, analysis of flow properties and pH measurements. In addition, Rg1 and Rb1 contents were monitored by UHPLC/MS. Different surfactants (phosphatidylcholine, monoacylphosphatidylcholine and polysorbate 80) and polymers (polyacrylic acid and hydroxyethylcellulose) were tested and compared for their compatibility with KRG extract. The results showed that incorporation of KRG extract led to a significantly reduced formulation pH in hydroxyethylcellulose gels (-22%), NEs (-15%) and carbomer gels (-4-5%). The dynamic viscosity was in the range of 24-28 Pas at 10 s-1 for carbomer gels. The highest storage stability and skin permeation were observed for a hydroalcoholic gel with carbomer 50,000 and TRIS buffer (each of 1% w/w), containing ethanol (20% w/w) and KRG extract (2% w/w). Ex vivo diffusion cell studies confirmed skin permeation of the moderately lipophilic Rg1, but not the more hydrophilic Rb1 with a larger molecular weight.

Rheological analysis of a novel phenylboronic acid-closomer gel

This study aims to characterize the rheological behavior of a novel phenylboronic acid (PBA)-based closomer nanoconjugate (Closogel) with potential application in pharmaceutical formulation. PBA was used as a cross-linking agent and model (antiviral) drug. The PBA loaded Closogel chemical structure was analyzed by boron (11B) NMR and Fourier transform infrared (FTIR) spectroscopy. The Closogel and control hydroxyethyl cellulose (HEC) gel were analyzed under oscillatory and continuous shear rheometry followed by mathematical modeling to characterize the gel flow behavior. The chemical analysis confirmed the existence of characteristic borate esters peaks and Boron chemical shifts within Closogel spectra. Due to its more flexible molecular structure, undiluted Closogel exhibited lower, yield stress, viscosity and relaxation time (30 Pa &163 Pa.s & 0.21 s vs 45 Pa &301 Pa.s & 0.39 s for HEC). Both Closogel and HEC gels exhibited a thixotropic behavior. The plastic undiluted and pseudoplastic 2.5 % w/v aqueous Closogels were more viscous than elastic (tan (δ) > 1) in the linear viscoelastic range. The Herschel-Bulkley model showed a significant fitting to all experimental data (R2 > 0.95). The 0.25 % w/v aqueous Closogel nearly exhibited a Newtonian behavior with a flow index of 0.93. These data suggest that PBA loaded Closomer-based gels have similar rheological behavior, with lower complex modulus than that of HEC gels, and they can be a promising platform used for delivery of topical antiviral or other bioactive agents.

Formulation and characterization of hydroxyethyl cellulose-based gel containing metronidazole-loaded solid lipid nanoparticles for buccal mucosal drug delivery

Local delivery of drug is a promising strategy to manage periodontitis characterized by chronic inflammation of the soft tissue surrounding the teeth. An optimized system should prolong the drug retention time and exhibit controlled drug permeation through the buccal mucosal layer. This study was aimed to develop hydroxyethyl cellulose (HEC)-based gel containing metronidazole (MTZ) loaded in solid lipid nanoparticles (SLNs), and to enhance the antimicrobial activity of MTZ. SLNs were prepared using a combination method of solvent evaporation and hot homogenization. The results showed that the fabricated SLNs, comprising of Precirol (2.93%, w/v), Tween 80 (1.8%, w/v), and the drug:lipid ratio of 19.3% (w/w), were approximately 200 nm in size, with a narrow distribution. The HEC (3%, w/w)-based gel formed a smooth, homogeneous structure and had preferable mechanical and rheological properties. Moreover, the MTZ-loaded SLNs-based HEC gel (equivalent to 1% of MTZ, w/w) exhibited a sustained in vitro drug release pattern, optimal ex vivo permeability, and enhanced in vitro antimicrobial activity after 24 h of treatment. These findings indicate the potential of the MTZ-loaded SLNs-based HEC formulation for local drug delivery at the buccal mucosa in managing periodontal disease.

Antifungal activity of peracetic acid against toxigenic fungal contaminants of maize and barley at the postharvest stage

Contamination of maize and barley grain during storage by the toxigenic fungi Aspergillus flavus (A. flavus) and Penicillium Verrucosum (P. verrucosum) is both an economic and a public health problem, especially in less industrialized countries. Peracetic acid (PA) is a compound used for the disinfection of food and food contact surfaces. Unlike other disinfectants, it leaves no toxic residues and its decomposition products (CH3COOH, O2 and H2O) are environmentally friendly. In order to apply PA to preserve maize and barley grain during storage, first, the Minimum Inhibitory Concentration (MIC) and Minimum Fungicidal Concentration (MFC) against both fungi were determined in a 96-well sterile microplates. Then, the antifungal activity of the volatile PA was determined by depositing it on filter paper and Hydroxyethylcellulose (HEC) gels, which were placed in airtight 1L flasks together with PDA and maize and barley grain inoculated with both fungi. The MFC in liquid medium of A. flavus and P. verrucosum was 93.8 and 187.5 mg/L respectively. However, PA doses of 300 and 200 mg/L on HEC gels were required in order to observe significant antifungal and antimycotoxigenic activity in maize and barley grain inoculated with these fungi.

Controlled release of iodine from cross-linked cyclodextrin metal-organic frameworks for prolonged periodontal pocket therapy

Effective therapeutic system to periodontitis was designed using cross-linked cyclodextrin metal-organic framework (COF) as carrier for iodine and further suspended in hydroxyethyl cellulose gel as I2@COF-HEC hydrogel. Inclusion of iodine within the COF was demonstrated by SR-FTIR spectral and characteristic DSC and TGA changes. Molecular modelling identified the interaction of iodine with both COF central cavity and individual cyclodextrin moieties of COF. In vitro results of study demonstrated that iodine release in artificial saliva from I2@COF-HEC hydrogel could be extended up to 5 days, which was slower than I2@COF particles. Using an in vivo rat model of periodontitis, micro-computed tomography of alveolar bone morphology demonstrated that I2@COF-HEC hydrogel showed similar effects in decreasing periodontal pocket depth and alveolar bone resorption to minocycline ointment, a periodontitis antibiotic. The I2@COF-HEC hydrogel is a novel local delivery device of iodine as a broad spectrum antimicrobial use for treatment of periodontitis.

Etodolac nanosuspension based gel for enhanced dermal delivery: in vitro and in vivo evaluation

Aim The objective of this study was to develop dermal nanosuspension (NS) based gel formulation of etodolac (ETD). Methods Etodolac nanosuspension (ETD-NS) was prepared by wet milling method and dispersed in hydroxypropyl methylcellulose (NS-HPMC) or hydroxyethyl cellulose (NS-HEC) gels. Rheologic and mechanical properties were investigated. In vitro and ex vivo permeability studies were performed. Topical anti-inflammatory and analgesic activity were evaluated in regard to carrageenan-induced inflammatory paw oedema and radiant heat tail-flick method, respectively. Results The ETD-NS with approximately 190 nm particle size (PS), 0.16 polydispersity index (PDI), and −15 mV zeta potential (ZP) values were obtained. The work of bioadhesion values of NS-HEC and NS-HPMC gels were 0.229 mJ/cm2 for both gels. Dermal permeation of ETD from NS-HEC gel (7.18%) was found significantly higher than the NS-HPMC gel (4.56%). Enhanced anti-inflammatory and analgesic activity of NS-HEC gels were observed in comparison with micronised ETD. Conclusions ETD-NS based gel formulation is promising for topical delivery of ETD.

Newly isolated lytic bacteriophages for Staphylococcus intermedius, structurally and functionally stabilized in a hydroxyethylcellulose gel containing choline geranate: Potential for transdermal permeation in veterinary phage therapy

In the present research work, we propose a new antimicrobial treatment for pyoderma via cutaneous permeation of bacteriophage particles conveyed in a hydroxyethylcellulose (HEC) gel integrating ionic liquid as a permeation enhancer. Ionic liquids are highly viscous fluids constituted exclusively by ions, that are usually hydrolytically stable and promote solubilization of amphipathic molecules such as proteins, hence serving as green solvents and promoting the transdermal permeation of biomolecules. In the research effort entertained herein, the synthesis and use of choline geranate for integrating a HEC gel aiming at the structural and functional stabilization of a cocktail of isolated lytic bacteriophage particles was sought, aiming at transdermal permeation in the antimicrobial treatment of animal pyoderma. The results obtained showed a high ability of the ionic liquid in enhancing transdermal permeation of the bacteriophage particles, with concomitant high potential of the HEC gel formulation in the antimicrobial treatment of animal skin infections.

The Role of Volume in the Perceptibility of Topical Vaginal Formulations: User Sensory Perceptions and Experiences of Heterosexual Couples During Vaginal Sex.

Users' sensory perceptions and experiences (USPEs; perceptibility) of drug formulations can critically impact product adoption and adherence, especially when products rely on appropriate user behaviors (timing of administration, dosing measurement) for effectiveness. The use of topical gel formulations for effective antihuman immunodeficiency virus/sexually transmitted infection (HIV/STI) vaginal microbicides has been associated with messiness and other use-associated challenges, resulting in low adherence. Nonetheless, such formulations remain attractive due to good pharmacokinetics and resulting pharmacodynamics through their volume and surface contact for drug delivery into luminal fluids and mucosa. Consequently, advocates and scientists continue to pursue topical forms [semisolid (e.g., gel, suppository); solid (e.g., film)] to deliver select drugs and offer user choice in HIV/STI prevention. The current data build on previously validated USPE scales evaluating perceptibility of gels with various biophysical/rheological properties. Specifically, increased formulation parameter space adds a new set of properties inherent in quick-dissolving film. We compared film, a product adding no discernable volume to the vaginal environment, to 2 and 3.5 mL hydroxyethyl cellulose gel to consider the impact of volume on user experience. We also examined the USPE scales for evaluation of male sexual partners' experiences. The original USPE scales functioned as expected. Additionally, six new USPE scales were identified in this enhanced parameter space. Significant differences were noted between USPEs in pairwise comparisons, with largest differences between film and high-volume gel. Product developers and behavioral scientists can use these scales to design products, optimizing user experience and maximizing adherence and delivery of efficacious anti-HIV/STI pharmaceuticals. They can be extended to evaluation of additional formulations, devices, and compartments, as well as single- and multipurpose pharmaceuticals. In broader contexts, USPEs could be of value in evaluating formulations and devices to prevent/treat other diseases (e.g., ophthalmologic, dermatologic). Steadfast attention should be given to patient experience, and, where applicable, experiences of partners and/or caregivers.

Multilayer thin-film flake dispersion gel for surface-enhanced Raman spectroscopy

Ag nanorod arrays/dielectrics/mirror-structured multilayer thin-film are well known, highly sensitive surface-enhanced Raman scattering (SERS) substrates that enhance the Raman scattering cross-section by the interference of light. However, extracting biomarkers directly from human skin using these solid substrates is difficult. To overcome this problem, we propose a multilayer thin-film flake dispersion gel by centrifugal mixing of the multilayer thin-film and hydroxyethyl cellulose (HEC) gel. The multilayer thin-film was prepared by serial bideposition using the dynamic oblique angle deposition technique. The mixing process was optimized to obtain flakes of ~10 {\mu}m so that the optical properties of the multilayer film can be preserved, and there is no risk of adverse effects on humans. The SERS features of the flakes dispersion gel were tested using 4, 4'-bipyridine (BPY). The BPY molecules diffused through the highly porous gel within a few seconds, generating significant SERS signals. The multilayer film flakes dispersion gel showed a SERS signal about 20 times better than the gel-dispersed Ag nanorod arrays without a multilayer film structure. These SERS active flakes dispersion gel can be used directly on the skin surface to collect body fluids from sweat, for biomarker sensing.

Green Synthesis, Characterization and Antimicrobial Evaluation of Silver Nanoparticles for an Intracanal Dressing.

Green chemistry has been applied in different areas due to the growing demands for renewable processes and one of them is nanotechnology. The aim of this study was to characterize a formulation containing silver nanoparticles (AgNPs) produced by a green synthesis and to evaluate its antimicrobial activity. The formulation will be used as an intracanal dressing exploiting the AgNPs' antimicrobial properties, which are crucial to prevent infections and bacterial reinfections that can compromise endodontic treatments. In the green synthesis, silver nitrate was employed as the precursor salt, maltose as a reducing agent, and gelatin as a stabilizing agent. The formulation was prepared mixing 50 % of a liquid containing the AgNPs and 50 % of hydroxyethylcellulose gel at 1.5 % with proper evaluation of the process inherent parameters. Techniques such as molecular absorption spectrometry and dynamic light scattering were used in characterization step. The antimicrobial activity of the AgNPs against Escherichia coli ATCC 25922, Enterococcus faecalis NCTC 775, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 25923 and Streptococcus mutans ATCC 25175 was verified according to National Comittee for Clinical Laboratory Standards (NCCLS) by determining minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). The obtained results indicated the formulation containing AgNPs produced by a green synthesis was properly characterized by the selected techniques. Furthermore, the formulation assessment proved that it is suitable for the proposal as well as it has potential to be used as an intracanal dressing since presented antimicrobial activity against all bacterial strains evaluated.

Anti-α 4 β 7 monoclonal antibody–conjugated nanoparticles block integrin α 4 β 7 on intravaginal T cells in rhesus macaques

Intravenous administration of anti-α4β7 monoclonal antibody in macaques decreases simian immunodeficiency virus (SIV) vaginal infection and reduces gut SIV loads. Because of potential side effects of systemic administration, a prophylactic strategy based on mucosal administration of anti-α4β7 antibody may be safer and more effective. With this in mind, we developed a novel intravaginal formulation consisting of anti-α4β7 monoclonal antibody-conjugated nanoparticles (NPs) loaded in a 1% hydroxyethylcellulose (HEC) gel (NP-α4β7 gel). When intravaginally administered as a single dose in a rhesus macaque model, the formulation preferentially bound to CD4+ or CD3+ T cells expressing high levels of α4β7, and occupied ~40% of α4β7 expressed by these subsets and ~25% of all cells expressing α4β7 Blocking of the α4β7 was restricted to the vaginal tract without any changes detected systemically.