Microneedle-assisted transdermal delivery of amlodipine besylate loaded nanoparticles.

Transdermal drug delivery has been developed to increase drug bioavailability and improve patient compliance. The current study was carried out to formulate and evaluate a transdermal delivery system loaded with biodegradable polymeric nanoparticles for sustained delivery of amlodipine besylate (AMB). For this purpose, AMB was incorporated into CS nanoparticles that were prepared via the ionic gelation method. Three formulations containing different blends of CS and tripolyphosphate were investigated for the preparation of the nanoparticles and evaluated for particle size (PS), zeta potential (ZP), loading capacity (LC), encapsulation efficiency (EE), scanning electron microscope (SEM), and drug release kinetics. The smallest observed particle size was 321.14 ± 7.21 nm (NP-3). Across all formulations, the highest observed EE% was 87.2 ± 0.12% (NP-2), and the highest observed LC% was 60.98 ± 0.08% (NP-2). Microneedles were formed by using 15% polyvinylalcohol (PVA) (F1), 15% PVA with 1% propylene glycol (PG) (F2), and 15% PVA with 5% PG (F3). On investigating drug release rates, it was observed that drug permeation and steady-state flux (Jss) both increased proportionally with increasing PG concentration. Nanomedicine, when combined with physical techniques, has opened new opportunities for the growth and development of transdermal delivery systems in the pharmaceutical industry. In conclusion, biodegradable polymeric nanoparticles loaded in hydrogel microneedles served as a potential system for the transdermal delivery of AMB in a controlled manner.

Beneath the Skin: A Review of Current Trends and Future Prospects of Transdermal Drug Delivery Systems.

The ideal drug delivery system has a bioavailability comparable to parenteral dosage forms but is as convenient and easy to use for the patient as oral solid dosage forms. In recent years, there has been increased interest in transdermal drug delivery (TDD) as a non-invasive delivery approach that is generally regarded as being easy to administer to more vulnerable age groups, such as paediatric and geriatric patients, while avoiding certain bioavailability concerns that arise from oral drug delivery due to poor absorbability and metabolism concerns. However, despite its many merits, TDD remains restricted to a select few drugs. The physiology of the skin poses a barrier against the feasible delivery of many drugs, limiting its applicability to only those drugs that possess physicochemical properties allowing them to be successfully delivered transdermally. Several techniques have been developed to enhance the transdermal permeability of drugs. Both chemical (e.g., thermal and mechanical) and passive (vesicle, nanoparticle, nanoemulsion, solid dispersion, and nanocrystal) techniques have been investigated to enhance the permeability of drug substances across the skin. Furthermore, hybrid approaches combining chemical penetration enhancement technologies with physical technologies are being intensively researched to improve the skin permeation of drug substances. This review aims to summarize recent trends in TDD approaches and discuss the merits and drawbacks of the various chemical, physical, and hybrid approaches currently being investigated for improving drug permeability across the skin.

Photolytic Controlled Release Formulation of Methotrexate Loaded in Chitosan/TiO2 Nanoparticles for Breast Cancer.

A new system composed of chitosan nanoparticles loaded with methotrexate (MTX-CS-NPs) and functionalized with photocatalytic TiO2 nanoparticles (TiO2-NPs) was prepared. This system is expected to initiate polymeric rupture of MTX-CS-NPs and subsequently release MTX, upon illumination with UV light. MTX-CS-NPs were prepared and characterized in terms of particle size, charge, polydispersity and drug release before and after coating with TiO2-NPs. The release of MTX in vitro was studied in dark, light and UV light. Finally, coated and uncoated MTX-CS-NPs were studied in vitro using MCF-7 cell line. The functionalized NPs were larger in size, more polydisperse and carried higher positive charges compared to the unfunctionalized NPs. The entrapment efficacy was high reaching 75% and was not affected by coating with MTX-CS-NPs. Further, less than 5% of methotrexate was released after 80 h from uncoated NPs and the release was not enhanced by UV illumination of the particles. In contrast, the release from functionalized NPs was enhanced, reaching 40% after 80 h, as the particles were stroked with UV light and as the amount of TiO2-NPs used in coating increased. Finally, coating the MTX-CS-NPs with TiO2-NPs significantly enhanced their cytotoxicity on MCF-7 cells. The coated MTX-CS-NPs recorded low cell viabilities compared to the other formulations. In conclusion, the drug release of MTX-CS-NPs could be triggered and controlled remotely by coating with TiO2-NPs, which maybe more effective in cancer treatment.

A novel formulation of chitosan nanoparticles functionalized with titanium dioxide nanoparticles.

Herein, chitosan nanoparticles (CS-NPs) were prepared and functionalized chemically with titanium dioxide nanoparticles (TiO2-NPs) to allow on-demand degradation of CS-NPs, using ultraviolet (UV) irradiation as a trigger. This is expected to allow drug release depending on patients' needs or physiological circumstances. Eleven formulations were arranged and their particle size, charge, and polydispersity were determined. The effect of CS-NPs size and the amount of TiO2-NPs, on the system collapse, was studied accordingly. Moreover, the collapse of these systems was examined using a fluorescence microscope after loading CS-NPs with Rhodamine. The formulations showed high monodispersity and had sizes ranged between 170 and 440 nm and charges ranged between +5 and +34 mV. Scanning electron microscope, Fourier-transform infrared spectroscopy, and X-ray diffraction proved the chemical deposition of TiO2-NPs on CS-NPs. The dye test showed that there are two factors that oppose each other and affected the deposition of TiO2-NPs on CS-NPs, the size of CS-NPs, and the amount of TiO2-NPs used. In addition, the dye test showed that the deposition of TiO2-NPs is a saturated process that relies on the amount of TiO2-NPs used initially. Finally, the intensity of Rhodamine released from these systems after illumination with UV light was related to the amount of TiO2-NPs deposited on CS-NPs. In conclusion, functionalization of CS-NPs with TiO2-NPs can be controlled and used to rupture CS-NPs on demand by illumination with UV light.