•Rheological and mechanical study of cellulose derivatives/HPMC; NaCMC poloxamer 407.•Cellulose derivatives content changed mechanical and rheological properties.•Formulations showed Tsol-gel to ...ensure easy administration and good retention.•Systems showed rheological synergism and softness dependent on polymer content.•17.5% poloxamer/3% HPMC or 1% NaCMC are useful for pharmaceutical-biomedical use.
Poloxamer 407 (polox407) is widely studied as thermogelling polymer, transitioning to a gel state when warmed Polox407 forms weak hydrogels with rapid dissolution in excess solvent. This study reports the development of binary systems composed of polox407 and hydroxypropyl methylcellulose (HPMC) or sodium carboxymethylcellulose (NaCMC) aiming to improve the rheological and mechanical properties of the hydrogel. The interaction between polox407 and cellulose derivatives was studied, and their interaction with biological surfaces predicted. The carbohydrates affected the mechanical and rheological behavior of polox407 in different ways, dependent on polymer type, concentration, and temperature. Tsol/gel and rheological interaction parameters were useful to select the most suitable formulations for topical or local application. Most of the binary systems exhibited plastic behavior, thixotropy and viscoelastic properties. Appropriate formulations were identified for local application, such as 17.5/3; 17.5/4; 20/3 and 20/4 (%, w/w) for polox407/HPMC; and 17.5/1; 17.5/1.5; 20/1 and 20/1.5 (%, w/w) for polox407/NaCMC.
The process of mucoadhesion has been widely studied using a wide variety of methods, which are influenced by instrumental variables and experiment design, making the comparison between the results of ...different studies difficult. The aim of this work was to standardize the conditions of the detachment test and the rheological methods of mucoadhesion assessment for semisolids, and introduce a texture profile analysis (TPA) method. A factorial design was developed to suggest standard conditions for performing the detachment force method. To evaluate the method, binary polymeric systems were prepared containing poloxamer 407 and Carbopol 971P
, Carbopol 974P
, or Noveon
Polycarbophil. The mucoadhesion of systems was evaluated, and the reproducibility of these measurements investigated. This detachment force method was demonstrated to be reproduceable, and gave different adhesion when mucin disk or ex vivo oral mucosa was used. The factorial design demonstrated that all evaluated parameters had an effect on measurements of mucoadhesive force, but the same was not observed for the work of adhesion. It was suggested that the work of adhesion is a more appropriate metric for evaluating mucoadhesion. Oscillatory rheology was more capable of investigating adhesive interactions than flow rheology. TPA method was demonstrated to be reproducible and can evaluate the adhesiveness interaction parameter. This investigation demonstrates the need for standardized methods to evaluate mucoadhesion and makes suggestions for a standard study design.
The intranasal administration of drugs using environmentally responsive formulations, employing a combination of hydroxypropyl methylcellulose (HPMC) and poloxamer 407 (P407), can result in release ...systems that may assist in the treatment of neurological diseases. Meloxicam, considered a potential adjuvant in the treatment of Alzheimer's disease, could be used in these platforms. The aim of this work was to develop a mucoadhesive, thermoresponsive, and nanostructured system containing HPMC for nose-to-brain administration of meloxicam. The initially selected systems were investigated for their rheological, mechanical, and micellar size characteristics. The systems were dilatant at 25 °C and pseudoplastic with a yield value at 37 °C, showing viscoelastic properties at both temperatures. The platform containing HPMC (0.1%, w/w) and P407 (17.5%, w/w) was selected and demonstrated good mucoadhesive properties, along with an appropriate in vitro release profile. HPMC could form a binary system with P407, displaying superior mucoadhesive and thermoresponsive properties for nose-to-brain meloxicam administration, indicating that the selected formulation is worthy of clinical studies.
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Recently, the number of new cases of cutaneous leishmaniasis has been of concern among health agencies. Research that offers new therapeutic alternatives is advantageous, especially those that ...develop innovative drugs. Therefore, this paper presents the incorporation of
Ducke and chlorophyll extract into Pluronic
F127 and Carbopol gels, under optimized polymer quantities. The chlorophyll extract (rich in photosensitizing compounds) was obtained by continuous-flow pressurized liquid extraction (PLE), a clean, environmentally friendly method. The system aims to act as as a leishmanicidal, cicatrizant, and antibiotic agent, with reinforcement of the photodynamic therapy (PDT) action. Rheological and mechanical analyses, permeation studies and bioadhesiveness analyses on human skin, and PDT-mediated activation of
were performed. The emulgels showed gelation between 13° and 15 °C, besides pseudoplastic and viscoelastic properties. Furthermore, the systems showed transdermal potential, by releasing chlorophylls and
Ducke into the deep layers of human skin, with good bioadhesive performance. The application of PDT reduced three logarithmic colony-forming units of
bacteria. The results support the potential of the natural drug for future clinical trials in treating wounds and cutaneous leishmania.
Microneedles (MNs) are a means to break the protective skin barrier in a minimally invasive way. By creating temporary micropores, they make biologically active agents available in the skin layers. ...Propolis (PRP) is a gum resin with a complex chemical composition, produced by bees
Apis mellifera
L. and showing several therapeutic properties (i.e., antibacterial, antiviral, antifungal, anti-inflammatory, healing, and immunomodulatory properties). The administration of PRP extracts by conventional routes has some disadvantages, such as running off over the skin in liquid or emulsion form. When taken orally, the extracts have a strong and unpleasant taste. The aim of this work was to fabricate and characterize microneedles containing polyvinyl alcohol, polyvinylpyrrolidone, poloxamer P407, and an ethanolic or glycolic extract of PRP. Also, the obtained structures were microscopically and mechanically characterized. The results of the mechanical analysis showed that formulations containing 3% of P407 presented the highest compression values in a hard surface, which was also confirmed by the height and base values of the morphological analysis and by the microscopy images. It was possible to design MNs and select the best formulations for future tests. MNs containing an ethanolic extract of PRP showed to be better structured than MNs containing a glycolic extract of PRP. The MNs obtained in these studies proved to be a promising platform for the topical application of PRP.
Mucoadhesive nanostructured systems comprising poloxamer 407 and Carbopol 974P
have already demonstrated good mucoadhesion, as well as improved mechanical and rheological properties. Curcumin ...displays excellent biological activity, mainly in oral squamous cancer; however, its physicochemical characteristics hinder its application. Therefore, the aim of this study was to develop nanostructured formulations containing curcumin for oral cancer therapy. The photophysical interactions between curcumin and the formulations were elucidated by incorporation kinetics and location studies. They revealed that the drug was quickly incorporated and located in the hydrophobic portion of nanometer-sized polymeric micelles. Moreover, the systems displayed plastic behavior with rheopexy characteristics at 37 °C, viscoelastic properties and a gelation temperature of 36 °C, which ensures increased retention after application in the oral cavity. The mucoadhesion results confirmed the previous findings with the nanostructured systems showing a residence time of 20 min in porcine oral mucosa under flow system conditions. Curcumin was released after 8 h and could permeate through the porcine oral mucosa. Cytotoxicity testing revealed that the formulations were selective to cancer cells over healthy cells. Therefore, these systems could improve the physicochemical characteristics of curcumin by providing improved release and permeation, while selectivity targeting cancer cells.
Summary
Aqueous extract rich in phenolic compounds and carbohydrates obtained as a co‐product during the trub‐debittering process can be used as a new sustainable ingredient to improve food quality ...properties. This water‐soluble extract (WE) was used for evaluating its own antioxidant capacity when added to processed cheese at up to 1.00% (w/w); and were also evaluated for total phenolic compounds, antioxidant activity, FTIR spectroscopy, lipid oxidation, oxidative stability, texture and rheological properties. WE addition increased the antioxidant activity of processed cheese by up to 88.40% and 81.90% for DPPH and ABTS, reduced the product lipid oxidation by up to 54.31% and showed greater oxidative stability (Rancimat) compared to the Control. Samples melting property was not changed, and samples with WE showed a more stable structure after melting. Use of WE showed that it can be used as natural antioxidant in processed cheese, improving its quality and texture properties.
Debittered trub (brewing waste) is an important source of protein source (70.26%). Trub and whey protein were used for 5% protein enrichment of ice cream frozen by liquid nitrogen. Three formulations ...were elaborated: ice cream standard (ICS), ice cream with whey protein (ICW) and ice cream with trub (ICT). Chemical composition, rheological properties, texture, overrun, melting rate, scanning electron microscopy and a sensorial test were performed. Results showed that ICT presented a higher viscosity, obtained on the upward curve up to 6.76 Pa s−1, consistency index (22.96 (Pa s−1)n), hysteresis area (140.40 mPa s−1) and hardness (31113.33 g) but a lower melting rate (0.38 g min−1), overrun (13.92%) and sensorial acceptability than the other formulations. The addition of trub debittered for protein enrichment improved ice cream properties and demonstrated that it could be used as a food ingredient.
Influence of trub addition in ice cream structure.
Psoriasis is an immune-mediated, chronic and recurrent inflammatory skin disease, prevalent worldwide, and represents an important burden in life quality of patients. The most common clinical variant ...is termed as psoriasis vulgaris or plaque psoriasis, which with an individualized and carefully monitored therapy can decrease the patients' morbidity and improving their life quality. The aim is to achieve disease control, minimize the adverse drug effects, and tailor the treatment to individual patient factors. Photodynamic therapy (PDT) is based on local or systemic administration of a non-toxic photosensitizer followed by irradiation with a particular wavelength to generate reactive oxygen species (ROS), mainly highly cytotoxic singlet oxygen (1O2). The generation of these species results in the attack to substrates involved in biological cycles causing necrosis and apoptosis of affected tissues. Photosensitizers are found in natural products and also obtained by partial syntheses from abundant natural starting compounds. They can be isolated at low cost and in large amounts from plants or algae. Therefore, this manuscript reviews the use of molecules from vegetal sources as photosensitizer agents for the PDT of psoriasis. Psoriasis pathogenesis, management and treatment were reviewed. PDT principles, fundamentals and utilization for the treatment of psoriasis were also discussed. Photosensitizers for PDT of psoriasis are also reviewed focusing on those from vegetal sources. Despite the PDT is utilized for the treatment of psoriasis, very little amount of photosensitizers from plant sources are utilized, such as chlorophyll derivatives and hypericin; however, other natural photosensitizers such as curcumin, could also be investigated. They could constitute a very important, safe and cheap alternative for the successful photodynamic treatment of psoriasis.
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Mucosa-mimetic materials are synthetic substrates which aim to replace animal tissue in mucoadhesion experiments. One potential mucosa-mimetic material is a hydrogel comprised of ...N-acryloyl-d-glucosamine and 2-hydroxyethylmethacrylate, which has been investigated as a surrogate for animal mucosae in the mucoadhesion testing of tablets and solution formulations. This study aims to investigate the efficacy of this mucosa-mimetic material in the testing of thermogelling semi-solid formulations, which transition from solution to gel upon warming. Two methods for assessing mucoadhesion have been used; tensile testing and a flow-through system, which allow for investigation under dramatically different conditions. It was found that the mucosa-mimetic material was a good surrogate for buccal mucosa using both testing methods. This material may be used to replace animal tissue in these experiments, potentially reducing the number of laboratory animals used in studies of this type.
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