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Caffeic acid (CA), a hydrophobic polyphenol with various pharmacological activities, exhibits a low aqueous solubility and sensitivity to light. In order to improve its chemical properties and overcome the limits in its application, the compound was loaded in P123 micelles (MCs) prepared using two polymer concentrations (10 and 20% w/w, MC10 and MC20). The micelles were characterised in terms of the size distribution, zeta potential, drug encapsulation efficiency, rheology, and cumulative drug release. Micellar formulations exhibited sizes in the range of 11.70 and 17.70 nm and a good polydispersion, indicating the formation of relatively small-sized micelles, which is favourable for drug delivery applications. Additionally, the stability and antioxidant profiles of the free CA and the CA loaded in micelles were studied. The results obtained on the free CA showed the formation of photodegradation products endowed with higher DPPH scavenging activity with respect to the pure compound. Instead, it was found that the incorporation of CA into the micelles significantly increased its solubility and decreased the photodegradation rate. Overall, the results indicate the successful formation of P123 micelles loaded with CA, with promising characteristics such as a small size, good encapsulation efficiency, sustained release profile, and improved light stability. These findings suggest the potentiality of these micelles as a delivery system for CA, thus enhancing its bioavailability. [ABSTRACT FROM AUTHOR]

In the current study, a smart release system responsive to temperature was developed to improve the efficiency of tetracycline (TC) in antibacterial therapy. The nanovesicles designed consist of a non-ionic surfactant, SPAN60, cholesterol and a phase change material (PCM) as a thermoresponsive gating material. Niosomes were prepared using an increasing amount of PCM and characterized in terms of size, zeta potential, colloidal stability and thermoresponsive properties. The vesicles that developed were homogenous in size, had good biocompatibility and stability for up to 3 months and demonstrated thermoresponsive behavior. A low drug leakage was observed at 37 °C, while a rapid release occurred at 42 °C, due to the faster diffusion rate of the drug trough the melted PCM. This controllable drug release capacity allows us to avoid premature drug release, minimizing unwanted and toxic effects and ensuring a long retention time in the nanodevice so that it reaches the infected sites. In addition, TC-loaded niosomes were screened to investigate their antibacterial activity against various Gram-positive and Gram-negative bacteria by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays. An interesting temperature-dependent antibacterial activity was observed against some bacterial strains: the niosomes activity against S. epidermis, for example, was improved by the temperature increase, as suggested by a reduction in MIC values from 112.81 to 14.10 μM observed at 37 and 42 °C, respectively. Taken together, the thermoresponsive platform developed allows us to use lower antibiotic amounts while ensuring therapeutic efficacy and, so, will advance the development of a novel antibacterial agent in clinical practice. [ABSTRACT FROM AUTHOR]

Background: This work proposes the development of new vesicular systems based on anesthetic compounds (lidocaine (LID) and capsaicin (CA)) and antimicrobial agents (amino acid-based surfactants from phenylalanine), with a focus on physicochemical characterization and the evaluation of antimicrobial and cytotoxic properties. Method: Phenylalanine surfactants were characterized via high-performance liquid chromatography (HPLC) and nuclear magnetic resonance (NMR). Different niosomal systems based on capsaicin, lidocaine, cationic phenylalanine surfactants, and dipalmitoyl phosphatidylcholine (DPPC) were characterized in terms of size, polydispersion index (PI), zeta potential, and encapsulation efficiency using dynamic light scattering (DLS), transmitted light microscopy (TEM), and small-angle X-ray scattering (SAXS). Furthermore, the interaction of the pure compounds used to prepare the niosomal formulations with DPPC monolayers was determined using a Langmuir balance. The antibacterial activity of the vesicular systems and their biocompatibility were evaluated, and molecular docking studies were carried out to obtain information about the mechanism by which these compounds interact with bacteria. Results: The stability and reduced size of the analyzed niosomal formulations demonstrate their potential in pharmaceutical applications. The nanosystems exhibit promising antimicrobial activity, marking a significant advancement in pharmaceutical delivery systems with dual therapeutic properties. The biocompatibility of some formulations underscores their viability. Conclusions: The proposed niosomal formulations could constitute an important advance in the pharmaceutical field, offering delivery systems for combined therapies thanks to the pharmacological properties of the individual components. [ABSTRACT FROM AUTHOR]

Background: This study aims to evaluate the percutaneous permeation profiles of caffeic acid (CA) from the cubic and hexagonal liquid crystalline phases of Pluronic P123/water mixtures. Method: The resulting drug-loaded mesophases were subjected to characterisation through deuterium nuclear magnetic resonance spectroscopy and polarised optical microscopy observations. These analyses aimed to evaluate the structural changes that occurred in the mesophases loading with CA. Additionally, steady and dynamic rheology studies were conducted to further explore their mechanical properties and correlate them to the supramolecular structure. Finally, CA release experiments were carried out at two different temperatures to examine the behaviour of the structured systems in a physiological or hyperthermic state. Results: As the concentration of the polymer increases, an increase in the viscosity of the gel is noted; however, the addition of caffeic acid increases microstructure fluidity. It is observed that the temperature effect conforms to expectations. The increase in temperature causes a decrease in viscosity and, consequently, an increase in the rate of permeation of caffeic acid. Conclusions: The CA permeation profile from the prepared formulations is mostly dependent on the structural organisation and temperature. Cubic mesophase LLC 30/CA showed greater skin permeation with good accumulation in the skin at both tested temperatures. [ABSTRACT FROM AUTHOR]

In this study, liposomes coated with novel multifunctional polymers were proposed as an innovative platform for tumor targeted drug delivery. Novel Folic acid–Cysteine-Thiolated chitosan (FTC) derivatives possessing active targeting ability and redox responsivity were synthesized, characterized, and employed to develop FTC-coated liposomes. Liposomes were characterized for size, surface charge and drug encapsulation efficiency before and after coating. The formation of a coating layer on liposomal surface was confirmed by the slight increase in particle size and by zeta-potential changes. FTC-coated liposomes showed a redox-dependent drug release profile: good stability at physiological conditions and rapid release of liposome-entrapped calcein in presence of glutathione. Moreover, the uptake and cytotoxic activity of doxorubicin-loaded FTC-coated liposomes was evaluated on murine B16-F10 and human SKMEL2 melanoma cancer cells. Results demonstrated enhanced uptake and antitumor efficacy of FTC-coated liposomes compared to control chitosan-coated liposomes in both cancer lines, which is attributed to higher cellular uptake via folate receptor-mediated endocytosis and to triggered drug release by the reductive microenvironment of tumor cells. The proposed novel liposomes show great potential as nanocarriers for targeted therapy of cancer. [ABSTRACT FROM AUTHOR]

Lidocaine is a local anaesthetic drug with an amphiphilic structure able to self-associate, under certain conditions, in molecular aggregates playing the role of both carrier and drug. The aim of this study was to determine the optimal conditions for obtaining vesicular carriers, called lidosomes. The new formulations were obtained using both lidocaine and lidocaine hydrochloride and different hydration medias (distilled water, acid, and basic aqueous solution). Lidosomes formulations were characterized in terms of size, ζ-potential, drug retained, stability formulation, and ex vivo permeation profile. Moreover, lidosomes were incorporated in two different gel structures: one based on carboxymethylcellulose and one based on pluronic F-127 to achieve suitable properties for a topical application. Results obtained showed that lidocaine showed a better performance to aggregate in vesicular carriers in respect to hydrochloride form. Consequently, only formulations comprised of lidocaine were studied in terms of skin permeation performance and as carriers of another model drug, capsaicin, for a potential combined therapy. Lidocaine, when in form of vesicular aggregates, acted as percutaneous permeation enhancer showing better permeation profiles with respect to drug solutions. Moreover, lidosomes created a significant drug depot into the skin from which the drug was available for a prolonged time, a suitable feature for a successful local therapy. [ABSTRACT FROM AUTHOR]

Aqueous solution in the absence and presence of added lithium chloride, sodium chloride, and hydrochloric acid occurring when Bola C-16 operates in real systems is described. A reasonable agreement between experimental data and calculated intensities was obtained, taking into account amino group hydrolysis and assuming that the interaction potential is a sum of hard sphere and coulombic contributions.

The natural capability shown by cationic vesicles in interacting with negatively charged surfaces or biomolecules has recently attracted increased interest. Important pharmacological advantages include the selective targeting of the tumour vasculature, the promotion of permeation across cell membranes, as well as the influence of cationic vesicles on drug delivery. Accordingly, cationic amphiphiles derived from amino acids may represent an alternative to traditional synthetic cationic surfactants due to their lower cytotoxicity. The importance of a synthesized lysine-based gemini surfactant (labelled C 6 (LL) 2 ) was evaluated in drug delivery by designing cationic niosomes as usable pharmaceutical tools of chemotherapeutics and antibiotics, respectively like methotrexate and tetracycline. The influence of formulation factors on the vesicles’ physical-chemical properties, drug entrapment efficiency, in vitro release and ex-vivo skin permeation were investigated. A niosomal gel containing the gemini surfactant was also tested as a viable multi-component topical formulation. Results indicate that in the presence of cholesterol, C 6 (LL) 2 was able to form stable and nanosized niosomes, loading hydrophilic or hydrophobic molecules. Furthermore, in vitro release studies and ex-vivo permeation profiles showed that C 6 (LL) 2 -based vesicles behave as sustained and controlled delivery systems in the case of parenteral administration, and as drug percutaneous permeation enhancers after topical application. Finally, cationic C 6 (LL) 2 acts as a carrier constituent, conferring peculiar and interesting functionality to the final formulation. [ABSTRACT FROM AUTHOR]

The synthesis of a novel functional biomaterial for wound healing treatment was carried out by adopting a free-radical grafting procedure in aqueous media. With this aim, ciprofloxacin (CFX) was covalently incorporated into collagen (T1C) chains employing an ascorbic acid/hydrogen peroxide redox pair as biocompatible initiator system. The covalent insertion of CFX in the polymeric chains was confirmed by FT-IR and UV analyses, while an antibacterial assay demonstrated the activity of the synthesized conjugate against Staphylococcus aureus and Escherichia coli, microorganisms that commonly infect wounds. A catechin blended conjugate was also tested in order to evaluate the ability to influence fibroblast cell growth. The observed antibacterial activity and stimulation of fibroblast growth support the applicability of CFX-T1C conjugate in wound treatment encouraging the healing process. [ABSTRACT FROM AUTHOR]

In this study, we report the results of our investigations on the percutaneous permeation profiles of Diclofenac sodium, Paracetamol, Propanolol hydrochloride, and α-Tocopherol from the different lyotropic liquid crystalline phases obtained by Pluronic P105/water mixtures, in order to understand if the particular assembly shown in the formulations could influence the delivery across the skin. Recent studies have focused on the Pluronic liquid crystalline phases to evaluate the potential use of these phases in drug delivery, but no comparative investigation has been yet performed on the drug permeation from the different liquid crystalline phases obtained by the same Pluronic surfactant. The cubic, hexagonal, and lamellar mesophases (loading the above-mentioned drug) were characterized by Deuterium Nuclear Magnetic Resonance spectroscopy and Polarized Optical Microscopy observations. Results revealed that the liquid crystalline gel microscopic structure obtained in the different formulations drastically affects the drug percutaneous availability. As a consequence these systems could be proposed as novel transdermal drug delivery systems. [ABSTRACT FROM AUTHOR]