22 factorial design-based biocompatible microneedle arrays containing artemether co-loaded with lumefantrine nanoparticles for transepidermal delivery

PVP-microneedle array for drug delivery: mechanical insight, biodegradation, and recent advances

Microneedle arrays are micron-sized needles usually attached to a supporting base or patch facilitated drug delivery for systemic effects. Polyvinylpyrrolidone (PVP) is a lactam polymer containing an internal amide linkage. Because of its versatility and biocompatibility, it has been widely utilized to treat several skin, bone and eye problems. Due to its specific and unique properties, the researchers realize its utility as a polymer of tremendous potential. PVP-based dissolvable microneedles have widely been utilized as a carrier for delivering DNAs, proteins, vitamins, and several biological macromolecules transdermally. However, it does not get biodegraded into the body. Therefore, the presence of its fragments in the body post-treatment needs proper justification. The adequate justification for the fate of the fragment's end products in the body will allow even better utilization of PVP. This review analyses and illustrates various experimental findings to highlight the most recent advancements and applications of PVP microneedles in drug delivery systems and cosmetology and the potential for PVP microneedles in treating dermal and systemic disorders. This review presents the expected mode of PVP biodegradation in aqueous and soil environments as a waste material, its inertness, biocompatibility, and the importance of PVP as a fabricating material, pharmaceutical uses, and non-toxic profile.

Polysaccharide from Atractylodes macrocephala Koidz binding with zinc oxide nanoparticles: Characterization, immunological effect and mechanism

Atractylodes macrocephala Koidz (A. macrocephala) has been used both as a traditional medicine and functional food for hundreds of years in Asia. And it has a variety of biological activities, such as enhancing the ability of immunity and modulating effect on gastrointestinal motility. In this study, a water-soluble polysaccharide with molecular weight of 2.743 × 10³ Da was isolated from the root of A. macrocephala. Polysaccharide from A. macrocephala (AMP) consisted of arabinose, galactose, glucose, xylose, mannose, ribose, galactose uronic acid, glucose uronic acid, with a percentage ratio of 21.86, 12.28, 34.19, 0.43, 0.92, 0.85, 28.79, and 0.67%, respectively. Zinc plays an important role in immune system. Therefore, we supposed that AMP binding with zinc oxide (ZnO) nanoparticles (AMP-ZnONPs) might be an effective immunostimulator. AMP-ZnONPs was prepared by Borch reduction, and its structural features were characterized by Scanning Electron Microscope (SEM), Transmission electron microscope (TEM), TEM-energy dispersive spectroscopy mapping (TEM-EDS mapping), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectrometer (XPS), X-ray diffraction (XRD), particle size and zeta-potential distribution analysis. Then, its immunostimulatory activity and the underlying mechanism were evaluated using RAW264.7 cells. The results showed that AMP-ZnONPs remarkably promoted cell proliferation, enhanced phagocytosis, the release of nitric oxide (NO), cytokines (IL-6 and IL-1β) and the expression of co-stimulatory molecules (CD80, CD86 and MHCII). Moreover, AMP-ZnONPs could promote the expression of Toll-like receptor 4 (TLR4), Myeloid differentiation factor 88 (MyD88), TNF receptor associated factor 6 (TRAF6), phospho-IκBα (P-IκBα) and phospho-p65 (P-p65), and TLR4 inhibitor (TAK242) inhibited the expression of these proteins induced by AMP-ZnONPs. Therefore, AMP-ZnONPs activated macrophages by TLR4/MyD88/NF-κB signaling pathway, indicating that AMP-ZnONPs could act as a potential immunostimulator in medicine and functional food.

Marine Polysaccharides in Tailor- Made Drug Delivery

Abstract:

Marine sources have attracted much interest as an emerging source of biomaterials in drug delivery applications. Amongst all other marine biopolymers, polysaccharides have been the mostly investigated class of biomaterials. The low cytotoxic behavior, in combination with the newly explored health benefits of marine polysaccharides has made it one of the prime research areas in the pharmaceutical and biomedical fields. In this review, we focused on all available marine polysaccharides, including their classification based on biological sources. The applications of several marine polysaccharides in recent years for tissue-specific novel drug delivery including gastrointestinal, brain tissue, transdermal, ocular, liver, and lung have also been discussed here. The abundant availability in nature, cost-effective extraction, and purification process along with a favorable biodegradable profile will encourage researchers to continue investigating marine polysaccharides for exploring newer applications in targeting specific delivery of therapeutics.

Microneedles in diagnostic, treatment and theranostics: An advancement in minimally-invasive delivery system

Microneedle (MN) technology plays an important role in biomedical engineering for their less intrusive access to the skin due to minimally or painless penetration, enhancement of drug permeability, improvement of detectability of biomolecules in the epidermal and dermal layers with therapeutic efficacy and safety. Furthermore, MNs possess some major disadvantages like difficulty in scale-up technique, variation in drug delivery pattern with respect to external environment of skin, blockage of arrays due to dermal tissues, induction of inflammation or allergy at the site of administration and restriction of dosing range based on the size of active. Additionally, microneedle acts as a transdermal theranostic device for monitoring the physiological parameters in clinical studies. The investigation of drug transfer mechanisms through microneedles includes coat and poke, poke and flow, poke and patch and poke and release method. This review article discusses different categories of microneedles with fabrication methods such as photolithography, laser cutting, 3D printing, etc. in therapeutic applications for treating cancer, diabetes, arthritis, obesity, neurological disorders, and glaucoma. Biosensing devices based on microneedles may detect target analytes directly in the interstitial fluid by penetrating the stratum corneum of the skin and thus microneedles-based devices can be considered as a single tool in diagnostic sensing and therapeutic administration of drugs inside the body. Moreover, the clinical status and commercial availability of microneedle devices are discussed in this review article to offer new insights to researchers and scientists. Continuous monitoring particularly for the determination of blood glucose concentration is one of the most important requirements for the development of next-generation healthcare devices. The aim of this review article focuses mainly on the theranostic applications of microneedles in various medical conditions such as malaria, glaucoma, cancer, etc.

Microneedle system: a modulated approach for penetration enhancement

The microneedles show advantages over transdermal drug delivery systems on account of better skin permeation bypassing the stratum corneum. To increase the flux of permeation, penetration enhancement techniques like physical and chemical methods are combined with a trans-epidermal delivery system across the skin causing minimal pain. These techniques include iontophoresis, sonophoresis, and electroporation for physical enhancement of drug delivery via topical route by either disrupting the structure of the stratum corneum or by creating pores/micro-channels within the skin. The use of chemical penetrants such as ethanol, lipids, surfactants, and terpenes improves the release kinetics by mechanisms like fluidization of lipids, denaturation of proteins, etc. A combination of microneedles and these techniques show a significant increase in the permeability of drugs across the skin by 5-10 times compared to microneedles alone. This review article focuses on various advanced strategies like the use of drug-polymer complexes, application of ultrasound frequency or tolerable electric current, formation of nano-formulations, etc. with microneedle delivery for transportation of high payload of actives, macromolecules, antibodies, gene, proteins, and peptides. In the near future, microneedle systems will offer potential targeted drug delivery, self-sealable administration across the skin, and minimally invasive vaccine transportation in cancer, diabetes, Alzheimer's, and cardiovascular diseases.HighlightsPhysical penetration enhancement techniques: iontophoresis, electroporation, and sonophoresis.Chemical penetration enhancers: polymers, lipids, surfactants.Strategies to use microneedle system with penetration enhancement techniques.The significant difference in the penetration ability of high payload actives.

Dissolving Microneedles Developed in Association with Nanosystems: A Scoping Review on the Quality Parameters of These Emerging Systems for Drug or Protein Transdermal Delivery

The largest organ of the body provides the main challenge for the transdermal delivery of lipophilic or high molecular weight drugs. To cross the main barrier of the skin, the stratum corneum, many techniques have been developed and improved. In the last 20 years, the association of microneedles with nanostructured systems has gained prominence for its versatility and for enabling targeted drug delivery. Currently, the combination of these mechanisms is pointed to as an emerging technology; however, some gaps need to be answered to transcend the development of these devices from the laboratory scale to the pharmaceutical market. It is known that the lack of regulatory guidelines for quality control is a hindrance to market conquest. In this context, this study undertakes a scoping review of original papers concerning methods applied to evaluate both the quality and drug/protein delivery of dissolving and hydrogel-forming microneedles developed in association with nanostructured systems.

Balancing Solid-State Stability and Dissolution Performance of Lumefantrine Amorphous Solid Dispersions: The Role of Polymer Choice and Drug-Polymer Interactions

Amorphous solid dispersions (ASDs) are of great interest due to their ability to enhance the delivery of poorly soluble drugs. Recent studies have shown that, in addition to acting as a crystallization inhibitor, the polymer in an ASD plays a role in controlling the rate of drug release, notably in congruently releasing formulations, where both the drug and polymer have similar normalized release rates. The aim of this study was to compare the solid-state stability and release performance of ASDs when formulated with neutral and enteric polymers. One neutral (polyvinylpyrrolidone-vinyl acetate copolymer, PVPVA) and four enteric polymers (hypromellose acetate succinate; hypromellose phthalate; cellulose acetate phthalate, CAP; methacrylic acid-methyl methacrylate copolymer, Eudragit L 100) were used to formulate binary ASDs with lumefantrine, a hydrophobic and weakly basic antimalarial drug. The normalized drug and polymer release rates of lumefantrine-PVPVA ASDs up to 35% drug loading (DL) were similar and rapid. No drug release from PVPVA systems was detected when the DL was increased to 40%. In contrast, ASDs formulated with enteric polymers showed a DL-dependent decrease in the release rates of both the drug and polymer, whereby release was slower than for PVPVA ASDs for DLs < 40% DL. Drug release from CAP and Eudragit L 100 systems was the slowest and drug amorphous solubility was not achieved even at 5% DL. Although lumefantrine-PVPVA ASDs showed fast release, they also showed rapid drug crystallization under accelerated stability conditions, while the ASDs with enteric polymers showed much greater resistance to crystallization. This study highlights the importance of polymer selection in the formulation of ASDs, where a balance between physical stability and dissolution release must be achieved.

Enhancement of immunopotentiation using tetanus toxoid-based nanoparticulate dissolvable microneedles

The main objective of the present study was to prepare and evaluate dissolvable microneedle patch containing nanoparticles of tetanus toxoid without the use of any adjuvant and its immunopotentiation activity. Immunization with microneedles is a novel approach in vaccines delivery with advantages such as convenience, simple, and non-invasive therapy. The gelatin nanoparticles were prepared by a layer-by-layer coating method using polystyrene sulfonate (PSS), polyallylamine hydrochloride (PLA), and PLGA. The filtered gelatin nanoparticles were later dispersed in the aqueous PVP K10 solution and integrated into a mold to develop microneedles. The nanoparticles and their dissolvable microneedle patches were evaluated using particle size, surface charge, entrapment efficiency, SEM analysis, in-vitro, and in-vivo studies. The particle size was found in the order of PLGA-coated nanoparticles > layered gelatin nanoparticles > aminated gelatin nanoparticles > gelatin nanoparticles and aminated gelatin nanoparticles showed maximum entrapment efficiency (92.6 ± 3.25%). The microscopic SEM images showed the spherical-shaped particle formation, verifies that the nanoparticles were formed. The gelatin nanoparticles followed the prolonged release for the period of 8 h whereas the nanoparticle-loaded dissolvable microneedles showed the controlled release pattern for 24 h. Aminated nanoparticulate microneedle showed the highest antibody production against tetanus toxoid. Hence, the nanoparticulate dissolvable microneedles-based immunopotentiation can be used as an alternative for delivery of tetanus toxoid.

Artemether-Loaded Zein Nanoparticles: An Innovative Intravenous Dosage Form for the Management of Severe Malaria

Artemether, an artemisinin derivative, is used in the management of life-threatening severe malaria. This study aimed to develop an intravenous dosage form of artemether using nanotechnology. Artemether-loaded zein nanoparticles were prepared by modified antisolvent precipitation using sodium caseinate as a stabilizer. Subsequently, the physicochemical properties of the nanoparticles were characterized; the in vitro hemolytic property was examined with red blood cells, while the pharmacokinetic profile was evaluated in Sprague–Dawley rats after intravenous administration. The artemether-loaded zein nanoparticles were found to display good encapsulation efficiency, excellent physical stability and offer an in vitro extended-release property. Interestingly, encapsulation of artemether into zein nanoparticles substantially suppressed hemolysis, a common clinical phenomenon occurring after artemisinin-based antimalarial therapy. Upon intravenous administration, artemether-loaded zein nanoparticles extended the mean residence time of artemether by ~80% in comparison to the free artemether formulation (82.9 ± 15.2 versus 45.6 ± 16.4 min, p < 0.01), suggesting that the nanoparticles may prolong the therapeutic duration and reduce the dosing frequency in a clinical setting. In conclusion, intravenous delivery of artemether by artemether-loaded zein nanoparticles appears to be a promising therapeutic option for severe malaria.

Single oral fixed-dose praziquantel-miltefosine nanocombination for effective control of experimental schistosomiasis mansoni

Background

The control of schistosomiasis has been centered to date on a single drug, praziquantel, with shortcomings including treatment failure, reinfection, and emergence of drug resistance. Drug repurposing, combination therapy or nanotechnology were explored to improve antischistosomal treatment. The aim of the present study was to utilize a novel combination of the three strategies to improve the therapeutic profile of praziquantel. This was based on a fixed-dose nanocombination of praziquantel and miltefosine, an antischistosomal repurposing candidate, co-loaded at reduced doses into lipid nanocapsules, for single dose oral therapy.

Methods

Two nanocombinations were prepared to provide 250 mg praziquantel-20 mg miltefosine/kg (higher fixed-dose) or 125 mg praziquantel-10 mg miltefosine/kg (lower fixed-dose), respectively. Their antischistosomal efficacy in comparison with a non-treated control and their praziquantel or miltefosine singly loaded counterparts was assessed in murine schistosomiasis mansoni. A single oral dose of either formulation was administered on the initial day of infection, and on days 21 and 42 post-infection. Scanning electron microscopic, parasitological, and histopathological studies were used for assessment. Preclinical data were subjected to analysis of variance and Tukeyʼs post-hoc test for pairwise comparisons.

Results

Lipid nanocapsules (~ 58 nm) showed high entrapment efficiency of both drugs (> 97%). Compared to singly loaded praziquantel-lipid nanocapsules, the higher nanocombination dose showed a significant increase in antischistosomal efficacy in terms of statistically significant decrease in mean worm burden, particularly against invasive and juvenile worms, and amelioration of hepatic granulomas (P ≤ 0.05). In addition, scanning electron microscopy examination showed extensive dorsal tegumental damage with noticeable deposition of nanostructures.

Conclusions

The therapeutic profile of praziquantel could be improved by a novel multiple approach integrating drug repurposing, combination therapy and nanotechnology. Multistage activity and amelioration of liver pathology could be achieved by a new praziquantel-miltefosine fixed-dose nanocombination providing 250 mg praziquantel-20 mg miltefosine/kg. To the best of our knowledge, this is the first report of a fixed-dose nano-based combinatorial therapy for schistosomiasis mansoni. Further studies are needed to document the nanocombination safety and explore its prophylactic activity and potential to hinder the onset of resistance to the drug components.

Engineering of Nanospheres Dispersed Microneedle System for Antihypertensive Action

BACKGROUND

A combinational therapy is mostly preferred in hypertension treatment because of low-dose and less side effects like pretibial edema, and gastrointestinal bleeding.

OBJECTIVE

So the objective of the present work was to formulate an advanced drug delivery system in the form of bio-responsive microneedles by incorporating nifedipine, a cardiodepressant and diltiazem, a vasodilator for effective synergism in the treatment of hypertension.

METHODS

The pH-responsive PLGA nanospheres of diltiazem were formulated using Water-in-Oil-in- Water (W/O/W) double emulsion and solvent-diffusion-evaporation technique. These nanospheres were added to nifedipine-PVP mixture and then incorporated into mold to develop microneedles.

RESULTS

The microneedles showed the release of nifedipine almost 96.93± 2.31% for 24 h due to high PVP solubilization. The nanospheres of diltiazem on contact with acidic pH of skin managed to form of CO2 bubbles and increase the internal pressure to burst PLGA shell due to pore formation. The mean blood pressure observed for the normal group was 89.58 ± 3.603 mmHg, whereas the treatment with the new formulation significantly reduced the mean blood pressure up to 84.11 ± 2.98 mmHg in comparison to the disease control group (109.9 ± 1.825 mm Hg).

CONCLUSION

This system co-delivers the drugs nifedipine and diltiazem in hypertension and shows an advance alternative approach over conventional drug delivery system.