The advances and the impact of nanostructured systems on therapeutics constitute a constantly evolving reality. New strategies have been developed for drug delivery control and for directing these ...systems to the targeted site improving the therapy. In this commentary, the lectins are briefly reviewed; their fundamentals and the proposed applications as ligands in nanostructured drug delivery systems are discussed.
Abstract This study investigated the development, validation and applicability of a high-pressure liquid chromatographic (HPLC) method for analysis of eprinomectin (EPR) in thermoresponsive ...bioadhesive systems aiming the future pour-on administration in animals. For the determination of the both two types of EPR (B1a and B1b), an HPLC method was developed and validated according to the international standardized guidelines. A factorial design 22 plus central point was utilized for the system design, rendering five formulations containing poloxamer 407, carbomer 974P, isopropanol and EPR. The formulations were evaluated as visual characteristics and sol-gel transition temperature (Tsol/gel). In addition, the applicability of HPLC method was evaluated by analysis of the selected formulations, analyzing the drug content and trapping efficiency. The HPLC method was selective, linear, homoscedasticity, precise, accurate and robust. Formulations F3 and F5 presented instability; however, F1, F2 and F4 were considered suitable. Tsol/gel of F1, F2 and F4 were compatible for use on the animal skin, and they displayed good recovery for EPR content and trapping efficiency. The proposed HPLC method for eprinomectin analysis was valid and could determine the eprinomectin content in systems F1, F2 and F4. Moreover, the methodology showed to be of importance for EPR analysis in thermoresponsive systems, displaying applicability.
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.
Hydrocolloids are used in food systems as emulsifiers, texturizing and stabilizers agents. Its use is also associated with health benefits such as reducing the risk of cardiovascular diseases. ...Beta-glucans and konjac glucomannan are commercially important examples. Konjac glucomannan is a polysaccharide extracted from konjac tuber (Amorphophallus konjac K. Koch) and is authorized as food additive in Europe and classified as Generally Recognized as Safe by the FDA. Due to its technological and nutritional applicability, it can be used in food as fat mimetic. Dairy food consumption has increased worldwide due to its functional and sensory properties. Processed cheese is a stable oil-in-water emulsion containing dairy protein, fat, emulsifying salts and other ingredients. There are few studies investigating the supplementation of low fat processed cheese with hydrocolloids. Low fat processed cheese was produced with 0.5% of commercial konjac glucomannan (CKG) or konjac flour (KF) with fat reductions of 25, 50, 75 and 100%. Physicochemical, color and texture profile analyzis were conducted. Rheological properties (G′, Gʺ, tan δ) and microstructure were determined on selected samples. Processed cheese with 50% fat reduction with added CKG (CKG50) showed the highest hardness value (327 g) and a strong elastic behavior. Fat reduction altered processed cheese color and melting properties. The standard sample (S) melted at 28 °C, while low fat cheeses with CKG or KF did not melt showing a more stable structure.
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•Commercial konjac glucomannan (CKG) strengthened low fat processed cheese network.•Konjac flour (KF) can be used as emulsifier in low fat processed cheese.•Fat reduction altered processed cheese color and melting properties.•Addition of CKG or KF improved the stability of low fat processed cheese.
Advances of nanotechnology led to the development of nanoparticulate systems with many advantages due to their unique physicochemical properties. The use of iron-oxide magnetic nanoparticles (IOMNPs) ...in pharmaceutical areas increased in the last few decades. This article reviews the conceptual information about iron oxides, magnetic nanoparticles, methods of IOMNP synthesis, properties useful for pharmaceutical applications, advantages and disadvantages, strategies for nanoparticle assemblies, and uses in the production of drug delivery, hyperthermia, theranostics, photodynamic therapy, and as an antimicrobial. The encapsulation, coating, or dispersion of IOMNPs with biocompatible material(s) can avoid the aggregation, biodegradation, and alterations from the original state and also enable entrapping the bioactive agent on the particle via adsorption or covalent attachment. IOMNPs show great potential for target drug delivery, improving the therapy as a consequence of a higher drug effect using lower concentrations, thus reducing side effects and toxicity. Different methodologies allow IOMNP synthesis, resulting in different structures, sizes, dispersions, and surface modifications. These advantages support their utilization in pharmaceutical applications, and getting suitable drug release control on the target tissues could be beneficial in several clinical situations, such as infections, inflammations, and cancer. However, more toxicological clinical investigations about IOMNPs are necessary.
Mucoadhesive drug delivery systems Carvalho, Flávia Chiva; Bruschi, Marcos Luciano; Evangelista, Raul Cesar ...
Brazilian Journal of Pharmaceutical Sciences,
03/2010, Letnik:
46, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Drug actions can be improved by developing new drug delivery systems, such as the mucoadhesive system. These systems remain in close contact with the absorption tissue, the mucous membrane, releasing ...the drug at the action site leading to a bioavailability increase and both local and systemic effects. Mucoadhesion is currently explained by six theories: electronic, adsorption, wettability, diffusion, fracture and mechanical. Several in vitro and in vivo methodologies are proposed for studying its mechanisms. However, mucoadhesion is not yet well understood. The aim of this study was to review the mechanisms and theories involved in mucoadhesion, as well as to describe the most-used methodologies and polymers in mucoadhesive drug delivery systems.
O efeito de fármacos pode ser potencializado através do desenvolvimento de novos sistemas de liberação como os sistemas mucoadesivos. Estes sistemas permanecem em contato íntimo com o tecido de absorção, as mucosas, liberando o fármaco no local de ação, com o consequente aumento da biodisponibilidade, podendo promover efeitos locais e sistêmicos. A mucoadesão, atualmente, é explicada por seis teorias, a eletrônica, da adsorção, da molhabilidade, da difusão, da fratura e a mecânica. Para estudar seus mecanismos e quantificá-la, são propostas várias metodologias in vitro e in vivo. Porém, a mucoadesão ainda não é totalmente compreendida. Esse trabalho tem por objetivo revisar os mecanismos e as teorias envolvidas na mucoadesão, além de descrever as metodologias e os polímeros mais utilizados em sistemas mucoadesivos para liberação de fármacos.
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.
Skin cancer (SC) is affecting an increasing number of people worldwide. Its lesions affect mainly the most exposed regions of the skin. SC is classified into to main categories: non-melanoma (basal ...cell carcinoma of the epidermis and squamous cell carcinoma) and melanoma (the abnormal proliferation of melanocytes, which is rarer, more hazardous, and more deadly). Prevention and early diagnosis are important actions, and surgery is often considered. After the removal of cancerous lesions, the local administration of medicine can guarantee anticancer therapeutic action, rapid healing and the recovery of tissue, ensuring the absence of recurrence. Magnetic gels (MGs) have attracted increased attention regarding their pharmaceutical and biomedical applications. They are magnetic nanoparticles (e.g., iron oxide nanoparticles) dispersed in a polymeric matrix, which constitute adaptive systems under a magnetic field. MGs can combine magnetic susceptibility, high elasticity, and softness, and are thus useful platforms for diagnostics, drug delivery, and also for hyperthermia. This manuscript reviews MGs as a technological strategy for the treatment of SC. An overview of SC and the treatment, types, and methods of preparing MGs are discussed. Moreover, the applications of MGs in SC and their future perspectives are considered. The combination of polymeric gels and magnetic nanoparticles continues to be investigated, and new products must hit the market. Clinical trials and new products are expected, due to the important advantages of MGs.
Brazilian green propolis has been widely used in food and pharmaceutical products due to its valuable source of phenolic compounds and versatile biological activities. The development and validation ...of analytical methods are extremely useful for the characterization and quality control of products containing propolis. Therefore, the aim of this study was to optimize, validate and investigate the applicability of a reversed-phase HPLC method for analysis of different types of Brazilian green propolis extracts (glycolic and ethanolic). The method showed to be selective for the propolis phenolic markers. The analysis of variance and residues demonstrated that the method had significant linear regression, without lack of fit. It was also a precise, accurate and robust method, which was of utmost importance to analyze both glycolic and ethanolic extracts and at different concentrations. Moreover, as these products can display most complex matrices to analyze, a valid HPLC method can also prove to be specific and versatile.
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