Physico-chemical characterization of formulations containing endomorphin-2 derivatives

Acrylated adhesive proteinic microneedle patch for local drug delivery and stable device implantation

Microneedle patches have been developed as favorable platforms for delivery systems, such as the locoregional application of therapeutic drugs, and implantation systems, such as electronic devices on visceral tissue surfaces. However, the challenge lies in finding materials that can achieve both biocompatibility and stable fixation on the target tissue. To address this issue, utilizing a biocompatible adhesive biomaterial allows the flat part of the patch to adhere as well, enabling double-sided adhesion for greater versatility. In this work, we propose an adhesive microneedle patch based on mussel adhesive protein (MAP) with enhanced mechanical strength via ultraviolet-induced polyacrylate crosslinking and Coomassie brilliant blue molecules. The strong wet tissue adhesive and biocompatible nature of engineered acrylated-MAP resulted in the development of a versatile wet adhesive microneedle patch system for in vivo usage. In a mouse tumor model, this microneedle patch effectively delivered anticancer drugs while simultaneously sealing the skin wound. Additionally, in an application of rat subcutaneous implantation, an electronic circuit was stably anchored using a double-sided wet adhesive microneedle patch, and its signal location underneath the skin did not change over time. Thus, the proposed acrylated-MAP-based wet adhesive microneedle patch system holds great promise for biomedical applications, paving the way for advancements in drug delivery therapeutics, tissue engineering, and implantable electronic medical devices.

Lignin-cellulose complexes derived from agricultural wastes for combined antibacterial and tissue engineering scaffolds for cutaneous leishmaniasis wounds

Bacterial infections in wounds significantly impair the healing process. The use of natural antibacterial products over synthetic antibiotics has emerged as a new trend to address antimicrobial resistance. An ideal tissue engineering scaffold to treat infected wounds should possess antibacterial properties, while simultaneously promoting tissue regrowth. Synthesis of hydrogel scaffolds with antibacterial properties using hemp shive (HT1/HT2) lignin, sugarcane bagasse (SCB) lignin and cellulose was carried out. All lignin samples had low molecular weights and were constituted of G-type β-5 dimers, linked by β-O-4 bonds, as determined by MALDI-TOF-MS. Hemp lignin was more cytotoxic to mouse fibroblasts (L929) compared to SCB lignin. All lignin samples demonstrated antibacterial properties against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis, with greater efficiency against Gram-negative strains. 3D hydrogels were engineered by crosslinking SCB lignin with SCB cellulose in varying weight ratios in the presence of epichlorohydrin. The stiffness of the hydrogels could be tailored by varying the lignin concentration. All hydrogels were biocompatible; however, better fibroblast adhesion was observed on the blended hydrogels compared to the 100% cellulose hydrogel, with the cellulose : lignin 70 : 30 hydrogel showing the highest L929 proliferation and best antibacterial properties with a 24-hour bacterial growth reduction ranging from 30.8 to 57.3%.

Brain-targeted delivery of Valsartan using solid lipid nanoparticles labeled with Rhodamine B; a promising technique for mitigating the negative effects of stroke

The brain is a vital organ that is protected from the general circulation and is distinguished by the presence of a relatively impermeable blood brain barrier (BBB). Blood brain barrier prevents the entry of foreign molecules. The current research aims to transport valsartan (Val) across BBB utilizing solid lipid nanoparticles (SLNs) approach to mitigate the adverse effects of stroke. Using a 3²-factorial design, we could investigate and optimize the effect of several variables in order to improve brain permeability of valsartan in a target-specific and sustained-release manner, which led to alleviation of ischemia-induced brain damage. The impact of each of the following independent variables was investigated: lipid concentration (% w/v), surfactant concentration (% w/v), and homogenization speed (RPM) on particle size, zeta potential (ZP), entrapment efficiency (EE) %, and cumulative drug release percentage (CDR) %. TEM images revealed a spherical form of the optimized nanoparticles, with particle size (215.76 ± 7.63 nm), PDI (0.311 ± 0.02), ZP (-15.26 ± 0.58 mV), EE (59.45 ± 0.88%), and CDR (87.59 ± 1.67%) for 72 hours. SLNs formulations showed sustained drug release, which could effectively reduce the dose frequency and improve patient compliance. DSC and X-ray emphasize that Val was encapsulated in the amorphous form. The in-vivo results revealed that the optimized formula successfully delivered Val to the brain through intranasal rout as compared to a pure Val solution and evidenced by the photon imaging and florescence intensity quantification. In a conclusion, the optimized SLN formula (F9) could be a promising therapy for delivering Val to brain, alleviating the negative consequences associated with stroke.

Porous Deproteinized Natural Rubber Film Loaded with Silver Nanoparticles for Topical Drug Delivery

The work demonstrated the use of natural rubber for topical drug delivery. The first objective was to fabricate a porous deproteinized natural rubber film loaded with silver nanoparticles. Characterizing and assessing its formulation was the second objective. Surface pH, mechanical properties, swelling ratio, erosion, moisture vapor transmission rate, scanning electron microscopy/energy dispersive X-ray analysis, and X-ray diffraction were evaluated. In vitro studies and antibacterial activity were assessed. It was discovered that silver nanoparticles could enter the film and that their concentrations ranged between 7.25 and 21.03 µg/cm2. The pH of the film's surface was 7.00. The mechanical properties of the film with silver nanoparticle loading differed from the blank film. After adding silver nanoparticles, the film eroded faster than before, but the swelling ratio was not affected significantly. Increased time utilization had an impact on the moisture vapor transmission rate of the film. Silver nanoparticles released easily from the film while there was less permeability. The dead pig-ear skin had significant silver nanoparticle accumulation. Potent antibacterial activity was seen in the film containing silver nanoparticles. The silver nanoparticle-loaded film may be used as a wound dressing for a topical film that promotes wound healing while also protecting the area from infection.

Development and Evaluation of a Novel Anti-Ageing Cream Based on Hyaluronic Acid and Other Innovative Cosmetic Actives

The importance of incorporating hyaluronic acid (HA) as a cosmetic ingredient in skin care formulations emerged lately because the amount of HA naturally found in the epidermis decreases with age, and when applied to the skin through cosmetic products, it confers hydration and reduces the appearance of wrinkles. Currently, the diversity of cosmetic products for mature skin and the use of various and innovative active ingredients supporting their anti-ageing effect represent ample proof that the cosmetic industry is currently relying on these actives. The main objective of this study was the development of an anti-ageing formulation, incorporating HA and different other active ingredients. The developed formulation contains a novel complex of natural waxes, with an essential role in the restoration of the skin's hydro-lipid barrier, in combination with innovative active ingredients-like low-molecular hyaluronic acid (LMW-HA), sodium hyaluronate (NaHA), ectoin, gold, and an anti-ageing botanical complex-contributing to optimal skin hydration specifically designed to reduce the visible signs of ageing. An important objective was represented by the skin compatibility and topography assessment after 28 days (D28) of regular application of the developed cream. Stability testing, physicochemical characteristics, and microbiological control, including efficacy testing of the used preservative (challenge test) were performed for the cosmetic formulation. In silico approaches were applied to demonstrate the safety of cosmetic-related substances and the risk assessment of the cosmetic formulation. Safety and instrumental evaluation were performed to demonstrate the skin tolerance-the compatibility and the efficacy, respectively-of the developed anti-ageing cream. As result, quality control of the developed cosmetic formulation evidenced an appropriate cosmetic preparation with desirable aspect and adequate physicochemical characteristics. The concentrations of restricted ingredients like preservatives and UV filters were in accordance with those recommended by the Regulation (EC) No. 1223/2009 and so were considered to be safe. Additionally, according to the margin of safety (MoS) calculation, cosmetic ingredients incorporated in the developed formulation could be considered safe. The developed formulation was very well tolerated, and wrinkle depth and length in the periorbital area were significantly reduced after 28-day cosmetic treatment. Subjects' assessment questionnaires revealed self-perceived benefits referring to the cosmetic qualities and efficacy of the anti-ageing cream. This study confirmed the skin tolerance and efficacy of the new complex anti-ageing cream incorporating HA, microencapsulated sodium hyaluronate, ectoin, and a botanical extract. The formulated cosmetic product could serve as a daily care for mature skin to alleviate the effects of skin ageing.

Nanocomposite Hydrogel Films Based on Sequential Interpenetrating Polymeric Networks as Drug Delivery Platforms

In this study, novel materials have been obtained via a dual covalent and ionic crosslinking strategies, leading to the formation of a fully interpenetrated polymeric network with remarkable mechanical performances as drug delivery platforms for dermal patches. The polymeric network was obtained by the free-radical photopolymerization of N-vinylpyrrolidone using tri(ethylene glycol) divinyl ether as crosslinker in the presence of sodium alginate (1%, weight%). The ionic crosslinking was achieved by the addition of Zn2+, ions which were coordinated by the alginate chains. Bentonite nanoclay was incorporated in hydrogel formulations to capitalize on its mechanical reinforcement and adsorptive capacity. TiO2 and ZnO nanoparticles were also included in two of the samples to evaluate their influence on the morphology, mechanical properties and/or the antimicrobial activity of the hydrogels. The double-crosslinked nanocomposite hydrogels presented a good tensile resistance (1.5 MPa at 70% strain) and compression resistance (12.5 MPa at a strain of 70%). Nafcillin was loaded into nanocomposite hydrogel films with a loading efficiency of up to 30%. The drug release characteristics were evaluated, and the profile was fitted by mathematical models that describe the physical processes taking place during the drug transfer from the polymer to a PBS (phosphate-buffered saline) solution. Depending on the design of the polymeric network and the nanofillers included, it was demonstrated that the nafcillin loaded into the nanocomposite hydrogel films ensured a high to moderate activity against S. aureus and S. pyogenes and no activity against E. coli. Furthermore, it was demonstrated that the presence of zinc ions in these polymeric matrices can be correlated with the inactivation of E. coli.

Cutaneous Polymeric-Micelles-Based Hydrogel Containing Origanum vulgare L. Essential Oil: In Vitro Release and Permeation, Angiogenesis, and Safety Profile In Ovo

Origanum vulgare var. vulgare essential oil (OEO) is known as a natural product with multiple beneficial effects with application in dermatology. Oregano essential oil represents a potential natural therapeutic alternative for fibroepithelial polyps (FPs), commonly known as skin tags. Innovative formulations have been developed to improve the bioavailability and stability of essential oils. In this study, we aimed to evaluate the morphology of a polymeric-micelles-based hydrogel (OEO-PbH), the release and permeation profile of oregano essential oil, as well as to assess in vivo the potential effects on the degree of biocompatibility and the impact on angiogenesis in ovo, using a chick chorioallantoic membrane (CAM). Scanning electron microscopy (SEM) analysis indicated a regular aspect after the encapsulation process, while in vitro release studies showed a sustained release of the essential oil. None of the tested samples induced any irritation on the CAM and the limitation of the angiogenic process was noted. OEO-PbH, with a sustained release of OEO, potentially enhances the anti-angiogenic effect while being well tolerated and non-irritative by the vascularized CAM, especially on the blood vessels (BVs) in the presence of leptin treatment. This is the first evidence of in vivo antiangiogenic effects of a polymeric-micelle-loaded oregano essential oil, with further mechanistic insights for OEO-PbH formulation, involving leptin as a possible target. The findings suggest that the OEO-containing polymeric micelle hydrogel represents a potential future approach in the pathology of cutaneous FP and other angiogenesis-related conditions.

Nafcillin-Loaded Photocrosslinkable Nanocomposite Hydrogels for Biomedical Applications

Skin infections are frequently treated via intravenous or oral administration of antibiotics, which can lead to serious adverse effects and may sometimes contribute to the proliferation of resistant bacterial strains. Skin represents a convenient pathway for delivering therapeutic compounds, ensured by the high number of blood vessels and amount of lymphatic fluids in the cutaneous tissues, which are systematically connected to the rest of the body. This study provides a novel, straightforward method to obtain nafcillin-loaded photocrosslinkable nanocomposite hydrogels and demonstrates their performance as drug carriers and antimicrobial efficacy against Gram-positive bacteria. The novel formulations obtained, based on polyvinylpyrrolidone, tri(ethylene glycol) divinyl ether crosslinker, hydrophilic bentonite nanoclay, and/or two types of photoactive (TiO₂ and ZnO) nanofillers, were characterized using various analytical methods (transmission electron microscopy (TEM), scanning electron microscopy-energy-dispersive X-ray analysis (SEM-EDX), mechanical tests (tension, compression, and shear), ultraviolet-visible spectroscopy (UV-Vis), swelling investigations, and via specific microbiological assays ("agar disc diffusion method" and "time-kill test"). The results reveal that the nanocomposite hydrogel possessed high mechanical resistance, good swelling abilities, and good antimicrobial activity, demonstrating a decrease in the bacteria growth between 3log₁₀ and 2log₁₀ after one hour of direct contact with S. aureus.

Development and cytotoxicity evaluation of multiple nanoemulsions for oral co-delivery of 5-fluorouracil and short chain triglycerides for colorectal cancer

Colorectal cancer (CRC) is the third most common cancer in the world, but current chemotherapy options are limited due to adverse effects and low oral bioavailability of drugs. In this study, we investigated the obtainment parameters and composition of new multiple nanoemulsions (MN) based on microemulsions for oral co-delivery of 5-fluorouracil (5FU) and short-chain triglycerides (SCT, either tributyrin or tripropionin). The area of microemulsion formation was increased from 14% to 38% when monocaprylin was mixed with tricaprylin as oil phase. Addition of SCT reduced this value to 24-26%. Using sodium alginate aqueous dispersion as internal aqueous phase (to avoid phase inversion) did not further affected the area but increased microemulsion viscosity by 1.5-fold. To obtain the MN, selected microemulsions were diluted in an external aqueous phase; droplet size was 500 nm and stability improved using polyoxyethylene (den Besten et al., 2013) oleyl ether at 1-2.5% as surfactant in the external phase and a dilution ratio of 1:1 (v/v). 5FU in vitro release could be better described by the Korsmeyer-Peppas model. No pronounced changes in droplet size were observed when selected MNs were incubated in buffers mimicking gastrointestinal fluids. The 5FU cytotoxicity in monolayer cell lines presenting various mutations was influenced by its incorporation in the nanocarrier, presence of SCT and cell mutation status. The MNs selected reduced the viability of tumor spheroids (employed as 3D tumor models) by 2.2-fold compared to 5FU solution and did not affect the survival of the G. mellonella, suggesting effectiveness and safety.

Weibull β value for the discernment of drug release mechanism of PLGA particles

Mathematical models are used to characterize and optimize drug release in drug delivery systems (DDS). One of the most widely used DDS is the poly(lactic-co-glycolic acid) (PLGA)-based polymeric matrix owing to its biodegradability, biocompatibility, and easy manipulation of its properties through the manipulation of synthesis processes. Over the years, the Korsmeyer-Peppas model has been the most widely used model for characterizing the release profiles of PLGA DDS. However, owing to the limitations of the Korsmeyer-Peppas model, the Weibull model has emerged as an alternative for the characterization of the release profiles of PLGA polymeric matrices. The purpose of this study was to establish a correlation between the n and β parameters of the Korsmeyer-Peppas and Weibull models and to use the Weibull model to discern the drug release mechanism. A total of 451 datasets describing the overtime drug release of PLGA-based formulations from 173 scientific articles were fitted to both models. The Korsmeyer-Peppas model had a mean Akaike Information Criteria (AIC) value of 54.52 and an n value of 0.42, while the Weibull model had a mean AIC of 51.99 and a β value of 0.55, and by using reduced major axis regression values, a high correlation was found between the n and β values. These results demonstrate the ability of the Weibull model to characterize the release profiles of PLGA-based matrices and the usefulness of the β parameter for determining the drug release mechanism.

Effect of Ionic Liquid on Silver-Nanoparticle-Complexed Ganoderma applanatum and Its Topical Film Formulation

Imidazolium-based ionic liquids have been widely utilized as versatile solvents for metal nanoparticle preparation. Silver nanoparticles and Ganoderma applanatum have displayed potent antimicrobial activities. This work aimed to study the effect of 1-butyl-3-methylimidazolium bromide-based ionic liquid on the silver-nanoparticle-complexed G. applanatum and its topical film. The ratio and conditions for preparation were optimized by the design of the experiments. The optimal ratio was silver nanoparticles: G. applanatum extract: ionic liquid at 97:1:2, and the conditions were 80 °C for 1 h. The prediction was corrected with a low percentage error. The optimized formula was loaded into a topical film made of polyvinyl alcohol and Eudragit^®, and its properties were evaluated. The topical film was uniform, smooth, and compact and had other desired characteristics. The topical film was able to control the release of silver-nanoparticle-complexed G. applanatum from the matrix layer. Higuchi's model was used to fit the kinetic of the release. The skin permeability of the silver-nanoparticle-complexed G. applanatum was improved by about 1.7 times by the ionic liquid, which might increase solubility. The produced film is suitable for topical applications and may be utilized in the development of potential future therapeutic agents for the treatment of diseases.

Transport of hydrocortisone in targeted layers of the skin by multi-lamellar liposomes

Hydrocortisone (HyC), a hydrophobic pharmaceutical active, was encapsulated in multi-lamellar liposomes (MLLs) composed of P100, a mixture of phospholipids, and Tween®80. Three different HyC-loaded formulations were designed to target the stratum corneum, the living epidermis and the hypodermis. The impact of encapsulation on their size, elasticity and zeta potential, the three key factors controlling MLLs skin penetration, was studied. Raman mapping of phospholipids and HyC allowed the localisation of both components inside an artificial skin, Strat-M®, demonstrating the efficiency of the targeting. Percutaneous permeation profiles through excised human skin were performed over 48 h, supporting results on artificial skin. Their modelling revealed that HyC encapsulated in MLLs, designed to target the stratum corneum and living epidermis, exhibited a non-Fickian diffusion process. In contrast, a Fickian diffusion was found for HyC administered in solution, in a pharmaceutical cream and in transdermal MLLs. These results allowed us to propose a mechanism of interaction between HyC-containing MLLs and the skin.

Improving the Dispersibility of TiO2 in the Colloidal System Using Trifunctional Spherosilicates

Titanium dioxide is a commonly used ingredient in cosmetics acting as a thickening agent and inorganic UV filter. However, TiO₂ is difficult to disperse, which causes problems in spreading the formulations. The solution to this problem is to modify the titanium dioxide surface to change its properties by creation of the new type of hybrid inorganic-organic UV filter. Therefore, this study aimed to functionalize titanium dioxide with organosilicon compounds and determine how this modification will affect the dispersibility of TiO₂ in the colloidal system and the stability of emulsions. First, the functionalized octaspherosilicates were obtained and characterized. Next, the synthesized compounds were applied as modifiers for titanium dioxide and were analyzed by FT-IR, UV-Vis, and laser diffraction. Furthermore, the hydrophilic-hydrophobic character was assessed by measuring the contact angle. The new materials were introduced into emulsions and the formulations were analyzed in terms of particle size distribution and stability by multiple light scattering. It was found that the modification of titanium dioxide with spherosilicates significantly improved both the stability of emulsion and the dispersibility of novel materials in the colloidal system compared to nonmodified TiO₂. The covalent binding of the modifier with the titanium dioxide had an impact on the stability of the emulsion.

Electrospun Mucoadhesive Zein/PVP Fibroporous Membrane for Transepithelial Delivery of Propranolol Hydrochloride

Mucoadhesive drug delivery systems have been extensively studied to effectively reduce the limitations of conventional drug delivery systems. Zein and polyvinyl pyrrolidone (PVP) are appraised for mucoadhesive properties. This study focuses on developing a mechanically stable zein/PVP electrospun membrane for propranolol hydrochloride (PL) transport. Fourier transform infrared, Raman spectra, and swelling studies gave evidence for PVP crosslinking, whereas circular dichroism spectroscopy revealed crosslinking of zein owing to the conformational change from α-helix to β-sheet. A 10 h thermal treatment of zein/PVP imparted 3.92 ± 0.13 MPa tensile strength to the matrix. Thermally crosslinked electrospun zein/PVP matrix showed 22.1 ± 0.1 g mm work of adhesion in porcine buccal mucosa tissue. Qualitative and quantitative evaluation of cytotoxicity in RPMI 2650 has been carried out. The in vitro drug release profile of PL from thermally crosslinked zein/PVP best fitted with the Korsmeyer-Peppas model. Immunostaining of β-catenin adherens junctional protein confirmed the absence of paracellular transport through the junctional opening. Still, drug permeation was observed through the porcine buccal mucosa, attributed to the transcellular transport of PL owing to its lipophilicity. The ex vivo permeation of PL through porcine buccal mucosa was also evaluated.

Ion-Triggered In Situ Gelling Intranasal Spray of Dronedarone Hydrochloride Nanocarriers: In Vitro Optimization and In Vivo Pharmacokinetic Appraisal

The current study aims to develop niosomal nanocarriers for intranasal delivery of dronedarone hydrochloride to ameliorate its limited bioavailability. Niosomes were prepared by ethanol injection method and optimized using 3² full factorial experimental design. Both Span® type (X1) and Span®: cholesterol ratio (X2) were set as independent variables. Vesicle size (Y1), polydispersity index (Y2), zeta potential (Y3), and entrapment efficiency (Y4) were set as responses. The optimal formula was further incorporated into an ion-sensitive in situ gelling polymer for intranasal delivery. Optimal formula (N7), which is composed of Span® 80: cholesterol (1:1), was of the least vesicle size (121.27 ± 13.31 nm), least polydispersity index (0.43 ± 0.073), highest zeta potential (-22.23 ± 2.84 mV) and highest entrapment efficiency (73.44 ± 2.8%). About 75.86% and 60.29% of dronedarone hydrochloride were released from N7 dispersion and in situ gel, respectively, within 12 h, compared to only 13.3% released from a drug-free suspension. In vivo pharmacokinetic study on male New Zealand rabbits resulted in significantly higher Cmax, AUC0-72, and AUC0-∞ of intranasal niosomal in situ gel compared to oral suspension. Almost twofold amplification of relative bioavailability was obtained after intranasal administration of niosomal in situ gel (195.7%) compared to oral suspension.

Development of Vaginal Carriers Based on Chitosan-Grafted-PNIPAAm for Progesterone Administration

Chitosan-based hydrogels possess numerous advantages, such as biocompatibility and non-toxicity, and it is considered a proper material to be used in biomedical and pharmaceutical applications. Vaginal administration of progesterone represents a viable alternative for maintaining pregnancy and reducing the risk of miscarriage and in supporting the corpus luteum during fertilization cycles. This study aimed to develop new formulations for vaginal administration of progesterone (PGT). A previously synthesized responsive chitosan-grafted-poly (N-isopropylacrylamide) (CS-g-PNIPAAm) was formulated in various compositions with polyvinyl alcohol (PVA) as external crosslinking agent to obtain pH- and temperature-dependent hydrogels; the hydrogels had the capacity to withstand shear forces encountered in the vagina due to its mechanism of swelling once in contact with vaginal fluids. Three different hydrogels based on grafted chitosan were analyzed via Fourier-transform infrared spectroscopy (FTIR), swelling tests, in vitro drug release, and bioadhesion properties by TA.XTplus texture analysis. A higher amount of PVA decreased the swelling and the bioadhesion capacities of the hydrogel. All hydrogels showed sensitivity to temperature and pH in terms of swelling and in vitro delivery characteristics. By loading progesterone, the studied hydrogels seemed to possess even higher sensitivity than drug-free matrices. The release profile of the active substance and the bioadhesion characteristics recommended the CS-g-PNIPAAm/PVA 80/20 +PGT (P1) hydrogel as a proper constituent for the vaginal formulation for progesterone administration.

Vesicles of yeast cell wall-sitagliptin to alleviate neuroinflammation in Alzheimer's disease

A cell-based drug delivery system based on yeast-cell wall loaded with sitagliptin, a drug with an anti-inflammatory effect, was developed to control neuroinflammation associated with Alzheimer's disease. The optimized nanoparticles had a spherical shape with a negative surface charge, and were shown to be less toxic than the carrier and sitagliptin. Moreover, the nanoparticles caused anti-inflammatory effects against tumor necrosis factor-alpha in mice model of neuroinflammation. The pharmacokinetics study showed the brain concentration of drug in the nanoparticles group was much higher than in the control group. To evaluate the effect of P-glycoprotein on brain entry of sitagliptin, the experiment was repeated with verapamil, as a P-glycoprotein inhibitor. Brain concentration of the nanoparticles group remained approximately unchanged, proving the "Trojan Horse" effect of the developed nanocarriers. The results are promising for using yeast-cell wall as a carrier for targeted delivery to immune cells for the management of inflammation.

Potential Enhancement of Metformin Hydrochloride in Solidified Reverse Micellar Solution-Based PEGylated Lipid Nanoparticles Targeting Therapeutic Efficacy in Diabetes Treatment

Metformin hydrochloride (MH) is a widely used oral biguanide antihyperglycemic (antidiabetic) drug with poor bioavailability which necessitates the development of novel drug delivery systems such as PEGylated solid lipid nanoparticles for improving its therapeutic activity. The aim of this study was to formulate, characterize and evaluate in vitro and in vivo pharmacodynamic properties of metformin–loaded PEGylated solid lipid nanoparticles (PEG-SLN) for improved delivery of MH. The lipid matrices (non-PEGylated lipid matrix and PEGylated lipid matrices) used in the formulation of both non-PEGylated (J₀) and PEGylated SLNs (J₁₀, J₂₀, J₄₀) were prepared by fusion using beeswax and Phospholipon ® 90H at 7:3 ratio with or without polyethylene glycol (PEG) 4000 (0, 10, 20 and 40% w/w), respectively. Representative lipid matrices (LM and PEG-LM) were loaded with MH by fusion and then characterized by differential scanning calorimetry (DSC) and Fourier transform infrared (FT-IR) spectroscopy. The PEG-SLNs were prepared by high shear hot homogenization using the lipid matrices (5% w/w), drug (MH) (1.0% w/w), sorbitol (4% w/w) (cryoprotectant), Tween ® 80 (2% w/w) (surfactant) and distilled water (q.s to 100% w/w) (vehicle). The non-PEGylated and PEGylated SLNs (J₀, J₁₀, J₂₀, J₄₀)) were characterized with respect to encapsulation efficiency (EE%), loading capacity (LC), morphology by scanning electron microscopy (SEM), mean particle size (Z_av) and polydispersity indices (PDI) by photon correlation spectroscopy (PCS), compatibility by FT-IR spectroscopy and in vitro drug release in biorelevant medium. Thereafter, in vivo antidiabetic study was carried out in alloxanized rats’ model and compared with controls (pure sample of MH and commercial MH- Glucophage®)). Solid state characterizations indicated the amorphous nature of MH in the drug loaded-lipid matrices. The PEG-SLNs were mostly smooth and spherical nanoformulations with Z_av and PDI of 350.00 nm and 0.54, respectively, for non-PEGylated SLNs, and in the range of 386.80–783.10 nm and 0.592 to 0.752, respectively, for PEGylated SLNs. The highest EE% and LC were noted in batch J₂₀ and were 99.28% and 16.57, respectively. There was no strong chemical interaction between the drug and excipients used in the preparation of the formulations. The PEGylated SLN (batch J₄₀) exhibited the highest percentage drug released (60%) at 8 h. The PEGylated SLNs showed greater hyperglycemic control than the marketed formulation (Glucophage ®) after 24 h. This study has shown that metformin–loaded PEGylated solid lipid nanoparticles could be employed as a potential approach to improve the delivery of MH in oral diabetic management, thus encouraging further development of the formulations.

Foaming with scCO2 and Impregnation with Cinnamaldehyde of PLA Nanocomposites for Food Packaging

Microcellular nanocomposite foams functionalized with cinnamaldehyde (Ci) were obtained through two-step supercritical foaming and impregnation processing. PLA nanocomposite foams with different C30B concentrations (1, 2, and 3 wt.%) were obtained by foaming with scCO2 at 25 MPa and 135 °C and impregnated with Ci at 12 MPa and 40 °C. The effect of the C30B content and Ci incorporation on the morphological, structural, thermal, and release properties of the developed foams were investigated. The incorporation of Ci was not influenced by C30B’s addition. The presence of C30B and Ci incorporation reduced the average pore diameter slightly and the crystallinity degree of the foams extensively. Simultaneously, the experimental and theoretical characterization of the Ci release from the PLA nanocomposite foams in EtOH 50% was analyzed. The mechanism of Ci release from the foams was defined as a quasi-Fickian diffusion process that could be successfully described using the Korsmeyer–Peppas model. The active PLA foams presented a higher potential of migration and faster release when compared with that reported in commonly used PLA films, showing that biopolymeric foams could be potentially used as active food packaging to improve the migration of active compounds with low migration potentials in order to improve their biological activity in foods.

Investigating the influence of excipient batch variation on the structure, consistency and physical stability of polysorbate 60-based topical vehicles

Fatty alcohol-polysorbate 60-water ternary systems were used as models to represent the continuous phases of the respective semisolid oil-in-water emulsions for topical delivery of cosmetic and medicinal agents. The influence of batch variation of polysorbate 60 and fatty alcohol on structure and consistency of these systems was investigated using microscopy, rheology, differential scanning calorimetry and X-ray scattering techniques. The polysorbate 60 : cetostearyl alcohol mixed emulsifying wax showed swelling in water, that is, the lamellar repeat distance continually augmented from 93 to 125 Å with water percentage 20-90%. Cetostearyl alcohol ternary systems were thicker than cetyl alcohol ones independently of polysorbate 60 batches used. All the ternary systems showed an initial increase in consistency over the first 2 weeks of storage, which was followed by slight changes in consistency (cetostearyl alcohol systems) due to the re-allocation of polysorbate 60 molecules in the gel network or significant breakdown of structure (cetyl alcohol systems) due to the transformation of swollen α-lamellar gel phase into β, γ crystals on 25°C storage. With all fatty alcohols, the consistency of polysorbate 60 ternary system was directly dependent upon interlamellar water thickness as governed by the length and distribution of polyoxyethylene groups within polysorbate 60 molecules. In relation with the composition of polysorbate 60 batches used, the consistency of ternary systems was higher when prepared with the polysorbate 60 batch containing a greater amount of sorbitan polyoxyethylene monoesters. It was proposed that the swollen α-crystalline gel phase could be better formed by sorbitan polyoxyethylene monoesters rather than sorbitan polyoxyethylene diesters.

Design of 3-aminophenol-grafted polymer-modified zinc sulphide nanoparticles as drug delivery system

Zinc sulphide (ZnS) nanoparticles were synthesized by the coprecipitation method. The ZnS nanoparticle surface was polymerized with allyl glycidyl ether (AGE), and 3-aminophenol was then deposited as a ligand on nanosorbent. The modified nanosorbent was investigated with Fourier transform infrared spectroscopy and thermogravimetric analysis. The particle size of the modified nanosorbent was studied with scanning electron microscopy. Some characteristic factors of the adsorption process such as pH and time were investigated for famotidine using the modified nanosorbent. The equilibrium adsorption study of famotidine by 3-aminophenol-grafted AGE/ZnS was analysed by adsorption isotherms of the Langmuir, Freundlich, and Temkin models. The famotidine-releasing process was investigated in simulated biological fluids (intestinal fluid at pH of 7.4 and gastric fluid at pH of 1.2) and demonstrated 65% and 73% famotidine release during periods of 30 h (pH = 7.4) and 60 min (pH = 1.2), respectively. These results reveal the optimal performance of 3-aminophenol-grafted AGE/ZnS for sustained drug delivery.

Mathematical Modeling of Water-Soluble Astaxanthin Release from Binary Polysaccharide/Gelatin Blend Matrices

Water-soluble AstaSana astaxanthin (AST) was loaded into 75/25 blend films made of polysaccharides (carboxymethyl cellulose (CMC), gum Arabic (GAR), starch sodium octenyl succinate (OSA), water-soluble soy polysaccharides (WSSP)) and gelatin (GEL) at levels of 0.25, 0.5, and 1%, respectively. Due to the presence of starch granules in the AST formulation, the supplemented films exhibited increased surface roughness as compared to the AST-free films. Apart from the CMC/GEL carrier, the migration of AST to water (25 °C, 32 h) was incomplete. Excluding the CMC-based carrier, the gradual rise in the AST concentration decreased the release rate. The Hopfenberg with time lag model provided the best fit for all release series data. Based on the quarter-release times (t25%), the 0.25% AST-supplemented OSA/GEL film (t25% = 13.34 h) ensured a 1.9, 2.2, and 148.2 slower release compared to the GAR-, WSSP- and CMC-based carriers, respectively. According to the Korsmeyer–Peppas model, the CMC-based films offered a quasi-Fickian release of AST (n < 0.5) with the burst effect (t100% = 0.5–1 h). In general, the release of AST from the other films was multi-mechanistic (n > 0.5), i.e., controlled at least by Fickian diffusion and the polymer relaxation (erosion) mechanism. The 1% AST-added WSSP/GEL system provided the most linear release profile.

Neurocosmetics in Skincare—The Fascinating World of Skin–Brain Connection: A Review to Explore Ingredients, Commercial Products for Skin Aging, and Cosmetic Regulation

The “modern” cosmetology industry is focusing on research devoted to discovering novel neurocosmetic functional ingredients that could improve the interactions between the skin and the nervous system. Many cosmetic companies have started to formulate neurocosmetic products that exhibit their activity on the cutaneous nervous system by affecting the skin’s neuromediators through different mechanisms of action. This review aims to clarify the definition of neurocosmetics, and to describe the features of some functional ingredients and products available on the market, with a look at the regulatory aspect. The attention is devoted to neurocosmetic ingredients for combating skin stress, explaining the stress pathways, which are also correlated with skin aging. “Neuro-relaxing” anti-aging ingredients derived from plant extracts and neurocosmetic strategies to combat inflammatory responses related to skin stress are presented. Afterwards, the molecular basis of sensitive skin and the suitable neurocosmetic ingredients to improve this problem are discussed. With the aim of presenting the major application of Botox-like ingredients as the first neurocosmetics on the market, skin aging is also introduced, and its theory is presented. To confirm the efficacy of the cosmetic products on the market, the concept of cosmetic claims is discussed.

Ocular microemulsion of brinzolamide: Formulation, physicochemical characterization, and in vitro irritation studies based on EpiOcular™ eye irritation assay

In recent years, the hydrophobic active substances have led researchers to develop new formulations to enhance bioavailability and dissolution rate; brinzolamide, a lipophilic drug belongs to carbonic anhydrase inhibitors, which cause reduction of intraocular pressure in patients suffering from glaucoma. Currently, the marketed product of brinzolamide is in the form of ocular drops; nonetheless, the conventional drops provide decreased therapeutic efficacy owing to their low bioavailability and pulsed drug release. Thus, the development of novel ocular formulations such as topical microemulsions is of high importance. In this work, the preparation of new microemulsions containing brinzolamide (0.2, 0.5 and 1% w/w) and comprised from isopropyl myristate, tween 80 and span 20 and Cremophor EL was performed. The obtained microemulsions were further characterized for their physicochemical properties. In addition, Fourier Transformed-Infrared spectroscopy was used touate the compatibility of active ingredients and components. In vitro release studies along with kinetic modeling were performed using the dialysis membrane method in simulated tear fluid. Bioadhesion studies were performed using Texture analysis. Finally, in vitro ocular irritation based on EpiOcular™ Eye Irritation Test and cytocompatibility studies was performed to examine any possible harm on ocular cells and predict in vivo safety profile.

Ethyl cellulose coated sustained release aspirin spherules for treating COVID-19: DOE led rapid optimization using arbitrary interface; applicable for emergency situations

This work attempts to resolve one of the key issues related to the design and development of sustained-release spherule of aspirin for oral formulations, tailored to treat COVID-19. For that, in the Design of Experiments (DOE) an arbitrary interface, "coating efficiency" (CE) is introduced and scaled the cumulative percentage coating (CPC) to get predictable control over drug release (DR). Subsequently, the granules containing ASP are converted to spherules and then to Ethyl cellulose (EC) Coated spherules (CS) by a novel bed coating during the rolling (BCDR) process. Among spherules, one with 0.35 mm than 0.71 mm shows required properties. The CS has a low 120⁰ angle by Optical Microscopy (OM), smooth surface without cracks by scanning electron microscopy (SEM), and better flow properties (Angle of repose 29.69 ± 0.78⁰, Carr's index 6.73 ± 2.24%, Hausner's Ratio 1.07 ± 0.03) than granules and spherules. Once certain structure-dependent control over release is attained (EC coated spherules shows 10% reduction in burst release (BR) than uncoated spherules showing a release of 80-91%) the predictability is achieved and Design of space (DOS) by DOE (CE-70.14%and CPC-200% and DR-61.54%) is established. The results of DOE to experimentally validated results were within 20% deviation. The aspirin is changing its crystal structure by powder X-ray diffraction (PXRD) and differential scanning calorimetry (DSC) from Form-I to Form-II showing polymorphism inside the drug reservoir with respect to the process. This CE and CPC approach in DOE can be used for delivery system design of other labile drugs similar to aspirin in emergency situations.

Endogenous opiates and behavior: 2017

This paper is the fortieth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2017 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).