The effect of ethanol evaporation on the properties of inkjet produced liposomes

Liposomes as versatile agents for the management of traumatic and nontraumatic central nervous system disorders: drug stability, targeting efficiency, and safety

Various nanoparticle-based drug delivery systems for the treatment of neurological disorders have been widely studied. However, their inability to cross the blood-brain barrier hampers the clinical translation of these therapeutic strategies. Liposomes are nanoparticles composed of lipid bilayers, which can effectively encapsulate drugs and improve drug delivery across the blood-brain barrier and into brain tissue through their targeting and permeability. Therefore, they can potentially treat traumatic and nontraumatic central nervous system diseases. In this review, we outlined the common properties and preparation methods of liposomes, including thin-film hydration, reverse-phase evaporation, solvent injection techniques, detergent removal methods, and microfluidics techniques. Afterwards, we comprehensively discussed the current applications of liposomes in central nervous system diseases, such as Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, traumatic brain injury, spinal cord injury, and brain tumors. Most studies related to liposomes are still in the laboratory stage and have not yet entered clinical trials. Additionally, their application as drug delivery systems in clinical practice faces challenges such as drug stability, targeting efficiency, and safety. Therefore, we proposed development strategies related to liposomes to further promote their development in neurological disease research.

Anticancer drug delivery: Investigating the impacts of viscosity on lipid-based formulations for pulmonary targeting

Pulmonary drug delivery via aerosolization is a non-intrusive method for achieving localized and systemic effects. The aim of this study was to establish the impact of viscosity as a novel aspect (i.e., low, medium and high) using various lipid-based formulations (including liposomes (F1-F3), transfersomes (F4-F6), micelles (F7-F9) and nanostructured lipid carriers (NLCs; F10-F12)) as well as to investigate their impact on in-vitro nebulization performance using Trans-resveratrol (TRES) as a model anticancer drug. Based on the physicochemical properties, micelles (F7-F9) elicited the smallest particle size (12-174 nm); additionally, all formulations tested exhibited high entrapment efficiency (>89 %). Through measurement using capillary viscometers, NLC formulations exhibited the highest viscosity (3.35-10.04 m2/sec). Upon using a rotational rheometer, formulations exhibited shear-thinning (non-Newtonian) behaviour. Air jet and vibrating mesh nebulizers were subsequently employed to assess nebulization performance using an in-vitro model. Higher viscosity formulations elicited a prolonged nebulization time. The vibrating mesh nebulizer exhibited significantly higher emitted dose (ED), fine particle fraction (FPF) and fine particle dose (FPD) (up to 97 %, 90 % and 64 µg). Moreover, the in-vitro release of TRES was higher at pH 5, demonstrating an alignment of the release profile with the Korsmeyer-Peppas model. Thus, formulations with higher viscosity paired with a vibrating mesh nebulizer were an ideal combination for delivering and targeting peripheral lungs.

Comprehensive insights into mechanism of nanotoxicity, assessment methods and regulatory challenges of nanomedicines

Nanomedicine has the potential to transform healthcare by offering targeted therapies, precise diagnostics, and enhanced drug delivery systems. The National Institutes of Health has coined the term "nanomedicine" to describe the use of nanotechnology in biological system monitoring, control, diagnosis, and treatment. Nanomedicine continues to receive increasing interest for the rationalized delivery of therapeutics and pharmaceutical agents to achieve the required response while reducing its side effects. However, as nanotechnology continues to advance, concerns about its potential toxicological effects have also grown. This review explores the current state of nanomedicine, focusing on the types of nanoparticles used and their associated properties that contribute to nanotoxicity. It examines the mechanisms through which nanoparticles exert toxicity, encompassing various cellular and molecular interactions. Furthermore, it discusses the assessment methods employed to evaluate nanotoxicity, encompassing in-vitro and in-vivo models, as well as emerging techniques. The review also addresses the regulatory issues surrounding nanotoxicology, highlighting the challenges in developing standardized guidelines and ensuring the secure translation of nanomedicine into clinical settings. It also explores into the challenges and ethical issues associated with nanotoxicology, as understanding the safety profile of nanoparticles is essential for their effective translation into therapeutic applications.

Development and characterization of novel surface engineered Depofoam: a QbD coupled failure modes and effects analysis risk assessment-based optimization studies

This study aimed to design and develop novel surface-engineered Depofoam formulations to extend the drug delivery to the prescribed time. The objectives are to prevent the formulation from burst release, rapid clearance by tissue macrophages, and instability and to analyze the impact of process and material variables in the characteristics of formulations. This work employed a quality-by-design coupled failure modes and effects analysis (FMEA)-risk assessment strategy. The factors for the experimental designs were chosen based on the FMEA results. The formulations were prepared by the double emulsification method followed by surface modification and characterized in terms of critical quality attributes (CQAs). The experimental data for all these CQAs were validated and optimized using the Box-Behnken design. A comparative drug release experiment was studied by the modified dissolution method. Furthermore, the stability of the formulation was also assessed. In addition, the impact of critical material attributes and critical process parameters on CQAs was evaluated using FMEA risk assessment. The optimized formulation method yielded high encapsulation efficiency (86.24 ± 0.69%) and loading capacity (24.13 ± 0.54%) with an excellent zeta potential value (-35.6 ± 4.55mV). The comparative in vitro drug release studies showed that more than 90% of the drug's release time from the surface-engineered Depofoam was sustained for up to 168 h without burst release and ensured colloidal stability. These research findings revealed that Depofoam prepared with optimized formulation and operating conditions yielded stable formulation, protected the drug from burst release, provided a prolonged release, and sufficiently controlled the drug release rate.

Spanlastics: a novel elastic drug delivery system with potential applications via multifarious routes of administration

Drug delivery systems (DDS) based on nanocarriers are designed to transport therapeutic agents to specific areas of the body where they are required to exhibit pharmacodynamic effect. These agents rely on an appropriate carrier to protect them from rapid degradation or clearance and enhance their concentration in target tissues. Spanlastics, an elastic, deformable surfactant-based nanovesicles have the potential to be used as a drug delivery vehicle for wide array of drug molecules. Spanlastics are formed by the self-association of non-ionic surfactants and edge activators in an aqueous phase and have gained attention as promising drug carriers due to their biodegradable, biocompatible, and non-immunogenic structure. In recent years, numerous scientific journals have published research articles exploring the potential of spanlastics to serve as a DDS for various types of drugs as they offer targeted delivery and regulated release of the drugs. Following brief introduction to spanlastics, their structure and methods of preparation, this review focuses on the delivery of various drugs using spanlastics as a carrier via various routes viz. topical, transdermal, ototopical, ocular, oral and nasal. Work carried out by various researchers by employing spanlastics as a carrier for enhancing therapeutic activity of different moieties has been discussed in detail.

A state-of-the-art liposome technology for glioblastoma treatment

Glioblastoma (GBM) is a challenging problem due to the poor BBB permeability of cancer drugs, its recurrence after the treatment, and high malignancy and is difficult to treat with the currently available therapeutic strategies. Furthermore, the prognosis and survival rate of GBM are still poor after surgical removal via conventional combination therapy. Owing to the existence of the formidable blood-brain barrier (BBB) and the aggressive, infiltrating nature of GBM growth, the diagnosis and treatment of GBM are quite challenging. Recently, liposomes and their derivatives have emerged as super cargos for the delivery of both hydrophobic and hydrophilic drugs for the treatment of glioblastoma because of their advantages, such as biocompatibility, long circulation, and ease of physical and chemical modification, which facilitate the capability of targeting specific sites, circumvention of BBB transport restrictions, and amplification of the therapeutic efficacy. Herein, we provide a timely update on the burgeoning liposome-based drug delivery systems and potential challenges in these fields for the diagnosis and treatment of brain tumors. Furthermore, we focus on the most recent liposome-based drug delivery cargos, including pH-sensitive, temperature-sensitive, and biomimetic liposomes, to enhance the multimodality in imaging and therapeutics of glioblastoma. Furthermore, we highlight the future difficulties and directions for the research and clinical translation of liposome-based drug delivery. Hopefully, this review will trigger the interest of researchers to expedite the development of liposome cargos and even their clinical translation for improving the prognosis of glioblastoma.

Development of invaethosomes and invaflexosomes for dermal delivery of clotrimazole: optimization, characterization and antifungal activity

The objective of this study was to develop novel invaethosomes (I-ETS) and invaflexosomes (I-FXS) to enhance the dermal delivery of clotrimazole (CZ). Twenty model CZ-loaded I-ETS and I-FXS formulations were created according to a face-centered central composite experimental design. CZ-loaded vesicle formulations containing a constant concentration of 0.025% w/v CZ and various amounts of ethanol, d-limonene, and polysorbate 20 as penetration enhancers were prepared using the thin film hydration method. The physicochemical characteristics, skin permeability, and antifungal activity were characterized. The skin permeability of the experimental CZ-loaded I-ETS/I-FXS was significantly higher than that of conventional ethosomes, flexosomes, and the commercial product (1% w/w CZ cream). The mechanism of action was confirmed to be skin penetration of low ethanol base vesicles through the disruption of the skin microstructure. The optimal I-ETS in vitro antifungal activity against C. albicans differed significantly from that of ETS and the commercial cream (control). The response surface methodology predicted by Design Expert® was helpful in understanding the complicated relationship between the causal factors and the response variables of the 0.025% w/v CZ-loaded I-ETS/I-FXS formulation. Based on the available information, double vesicles seem to be promising versatile carriers for dermal drug delivery of CZ.

Current Applications of Liposomes for the Delivery of Vitamins: A Systematic Review

Liposomes have been used for several decades for the encapsulation of drugs and bioactives in cosmetics and cosmeceuticals. On the other hand, the use of these phospholipid vesicles in food applications is more recent and is increasing significantly in the last ten years. Although in different stages of technological maturity-in the case of cosmetics, many products are on the market-processes to obtain liposomes suitable for the encapsulation and delivery of bioactives are highly expensive, especially those aiming at scaling up. Among the bioactives proposed for cosmetics and food applications, vitamins are the most frequently used. Despite the differences between the administration routes (oral for food and mainly dermal for cosmetics), some challenges are very similar (e.g., stability, bioactive load, average size, increase in drug bioaccessibility and bioavailability). In the present work, a systematic review of the technological advancements in the nanoencapsulation of vitamins using liposomes and related processes was performed; challenges and future perspectives were also discussed in order to underline the advantages of these drug-loaded biocompatible nanocarriers for cosmetics and food applications.

Impact of dispersion media and carrier type on spray-dried proliposome powder formulations loaded with beclomethasone dipropionate for their pulmonary drug delivery via a next generation impactor

Drug delivery via aerosolization for localized and systemic effect is a non-invasive approach to achieving pulmonary targeting. The aim of this study was to prepare spray-dried proliposome (SDP) powder formulations to produce carrier particles for superior aerosolization performance, assessed via a next generation impactor (NGI) in combination with a dry powder inhaler. SDP powder formulations (F1-F10) were prepared using a spray dryer, employing five different types of lactose carriers (Lactose monohydrate (LMH), lactose microfine (LMF), lactose 003, lactose 220 and lactose 300) and two different dispersion media. The first dispersion medium was comprised of water and ethanol (50:50% v/v ratio), and the second dispersion medium comprised wholly of ethanol (100%). In the first dispersion medium, the lipid phase (consisting of Soya phosphatidylcholine (SPC as phospholipid) and Beclomethasone dipropionate (BDP; model drug) were dissolved in ethanol and the lactose carrier in water, followed by spray drying. Whereas in second dispersion medium, the lipid phase and lactose carrier were dispersed in ethanol only, post spray drying. SDP powder formulations (F1-F5) possessed significantly smaller particles (2.89 ± 1.24-4.48 ± 1.20 μm), when compared to SDP F6-F10 formulations (10.63 ± 3.71-19.27 ± 4.98 μm), irrespective of lactose carrier type via SEM (scanning electron microscopy). Crystallinity of the F6-F10 and amorphicity of F1-F15 formulations were confirmed by XRD (X-ray diffraction). Differences in size and crystallinity were further reflected in production yield, where significantly higher production yield was obtained for F1-F5 (74.87 ± 4.28-87.32 ± 2.42%) then F6-F10 formulations (40.08 ± 5.714-54.98 ± 5.82%), irrespective of carrier type. Negligible differences were noted in terms of entrapment efficiency, when comparing F1-F5 SDP formulations (94.67 ± 8.41-96.35 ± 7.93) to F6-F10 formulations (78.16 ± 9.35-82.95 ± 9.62). Moreover, formulations F1-F5 demonstrated significantly higher fine particle fraction (FPF), fine particle dose (FPD) and respirable fraction (RF) (on average of 30.35%, 890.12 μg and 85.90%) when compared to counterpart SDP powder formulations (F6-F10). This study has demonstrated that when a combination of water and ethanol was employed as dispersion medium (formulations F1-F5), superior formulation properties for pulmonary drug delivery were observed, irrespective of carrier type employed.

Lipid-Based Drug Delivery Systems for Diseases Managements

Liposomes are tiny lipid-based vesicles composed of one or more lipid bilayers, which facilitate the encapsulation of hydrophilic, lipophilic, and amphiphilic biological active agents. The description of the physicochemical properties, formulation methods, characteristics, mechanisms of action, and large-scale manufacturing of liposomes as delivery systems are deeply discussed. The benefits, toxicity, and limitations of the use of liposomes in pharmacotherapeutics including in diagnostics, brain targeting, eye and cancer diseases, and in infections are provided. The experimental approaches that may reduce, or even bypass, the use of liposomal drug drawbacks is described. The application of liposomes in the treatment of numerous diseases is discussed.

Can Liposomes Survive Inkjet Printing? The Effect of Jetting on Key Liposome Attributes for Drug Delivery Applications

Purpose

Inkjet printing has the potential to enable novel personalized and tailored drug therapies based on liposome and lipid nanoparticles. However, due to the significant shear force exerted on the jetted fluids, its suitability for shear-sensitive materials such as liposomes, has not been verified. We have conducted a proof-of-concept study to examine whether the particle concentration and size distribution of placebo liposomes are affected by common inkjet/dispensing technologies.

Methods

We have subjected three types of liposome-containing fluids ("inks") to two different commercial dispensing/jetting technologies, which are relevant to most drug printing approaches. The liposome jetting processes were observed in real-time using strobographic imaging techniques. The phospholipid concentrations and particle size distributions were determined before and after jetting via enzymatic colorimetric and dynamic light scattering methods, respectively.

Results

Our results have shown that the jetting dynamics of the liposome inks are well predicted by the established inkjet printing regime map based on their physical properties and the jetting conditions. Importantly, although significant shear forces were confirmed during jetting, the liposome concentrations and particle size distributions in the collected samples remain largely unaffected.

Conclusion

These findings, we believe, provide the essential proof-of-concept to encourage further development in this highly topical research area.

Antimicrobial and Antibiofilm Activity of Cinnamon (Cinnamomum burmanii) Extract on Periodontal Pathogens—An in vitro study

Objective  The aim of this study was to analyze the antibiofilm effectiveness of cinnamon ( Cinnamomum burmanii ) ethanol extract against Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans in vitro .

Material and   Methods Phytochemical tests were done to identify the cinnamon extract active substances. Furthermore, a crystal violet biofilm assay was used to analyze biofilm detachment after treatment with different concentrations (15, 10, 7.5, 5, and 2.5%) of cinnamon. Biofilm turbidity was measured at 595-nm wavelength using a microplate reader. Additionally, MTT assay was done to analyze the toxicity level of cinnamon extract on fibroblast cells.

Statistical Analysis  The obtained data were analyzed for normality using the Kolmogorov–Smirnov test. The differences between each group were analyzed using a one-way analysis of variance statistical test, with a significance level of p <0.05.

Results  The results showed that the ethanol extract of cinnamon contains active compounds of flavonoids, alkaloids, saponins, tannins, quinones, and terpenoids. MTT result showed the cinnamon extract to be nontoxic. The biofilm assay results showed that all cinnamon concentrations exhibited an antibiofilm effect against P. gingivalis and A. actinomycetemcomitans in all incubation time compared with a negative control ( p <0.05).

Conclusions  Cinnamon extracts were effective in inhibiting biofilm of periodontal pathogens. Cinnamon extract might be useful as an alternative therapy for periodontal diseases. Future studies are still needed to confirm this result in vivo to analyze the efficacy of this extract as mouthwash.

A Comprehensive Review on Novel Liposomal Methodologies, Commercial Formulations, Clinical Trials and Patents

Liposomes are well-recognized and essential nano-sized drug delivery systems. Liposomes are phospholipid vesicles comprised of cell membrane components and have been employed as artificial cell models to mimic structure and functions of cells and are of immense use in various biological analyses. Liposomes acquire great advantages and provide wide range of applications as useful drug carriers in pre-clinical and clinical trials. This review summarizes exclusively on scalable techniques for liposome preparation and focuses on the strengths and limitations with respect to industrial applicability. Also, this review discusses the updated recent advancements in biomedical applications with a mention of key highlights of commercially available formulations, clinical trials and patents in recent past. Furthermore, this review also provides brief information of the classification, composition and characterization of liposomes.

Fabrication, characterization and optimization of nanostructured lipid carrier formulations using Beclomethasone dipropionate for pulmonary drug delivery via medical nebulizers

Aerosolization is a non-invasive approach in drug delivery for localized and systemic effect. Nanostructured lipid carriers (NLCs) are new generation versatile carriers, which offer protection from degradation and enhance bioavailability of poorly water soluble drugs. The aim of this study was to develop and optimize NLC formulations in combination with optimized airflow rates (i.e. 60 and 15 L/min) and choice of medical nebulizers including Air jet, Vibrating mesh and Ultrasonic nebulizer for superior aerosolization performance, assessed via a next generation impactor (NGI). Novel composition and combination of NLC formulations (F1 - F15) were prepared via ultrasonication method, employing five solid lipids (glycerol trimyristate (GTM), glycerol trilaurate (GTL), cetyl palmitate (CP), glycerol monostearate (GMS) and stearic acid (SA)); and three liquid lipids (glyceryl tributyrate (GTB), propylene glycol dicaprylate/dicaprate (PGD) and isopropyl palmitate (IPP)) in 1:3 w/w ratios (i.e. combination of one solid and one liquid lipid), with Beclomethasone dipropionate (BDP) incorporated as the model drug. Out of fifteen BDP-NLC formulations, the physicochemical properties of formulations F7, F8 and F10 exhibited desirable stability (one week at 25 °C), with associated particle size of ~241 nm, and >91% of drug entrapment. Post aerosolization, F10 was observed to deposit notably smaller sized particles (from 198 to 136 nm, 283 to 135 nm and 239 to 157 nm for Air jet, Vibrating mesh and Ultrasonic nebulizers, respectively) in all stages (i.e. from stage 1 to 8) of the NGI, when compared to F7 and F8 formulations. Six week stability studies conducted at 4, 25 and 45 °C, demonstrated F10 formulation stability in terms of particle size, irrespective of temperature conditions. Nebulizer performance study using the NGI for F10 identified the Air jet to be the most efficient nebulizer, depositing lower concentrations of BDP in the earlier stages (1-3) and higher (circa 82 and 85%) in the lateral stages (4-8) using 60 and 15 L/min airflow rates, when compared to the Vibrating mesh and Ultrasonic nebulizers. Moreover, at both airflow rates, the Air jet nebulizer elicited a longer nebulization time of ~42 min, facilitating aerosol inhalation for prophylaxis of asthma with normal tidal breathing. Based on characterization and nebulizer performance employing both 60 and 15 L/min airflow rates, the Air jet nebulizer offered enhanced performance, exhibiting a higher fine particle dose (FPD) (90 and 69 µg), fine particle fraction (FPF) (70 and 54%), respirable fraction (RF) (92 and 69%), and lower mass median aerodynamic diameter (MMAD) (1.15 and 1.62 µm); in addition to demonstrating higher drug deposition in the lateral parts of the NGI, when compared to its counterpart nebulizers. The F10 formulation used with the Air jet nebulizer was identified as being the most suitable combination for delivery of BDP-NLC formulations.

Proliposome powder or tablets for generating inhalable liposomes using a medical nebulizer

Purpose

The aim of this study was to develop and compare proliposome powder and proliposome tablet formulations for drug delivery from a Pari-LC Sprint nebulizer.

Methods

Proliposome powders were prepared by the slurry method and sorbitol or mannitol carbohydrate carrier were used in a 1:10 and 1:15 w/w lipid phase to carrier ratio. Beclometasone dipropionate (BDP; 2 mol%) was incorporated in the lipid phase. Proliposome powders were compressed into tablets, and liposomes were generated from proliposome powders or tablets within the nebulizer reservoir for subsequent aerosolization.

Results

Comparatively, shorter sputtering times were reported for the tablet formulations (≈ < 2.7±0.45 min), indicating uniform aerosolization. Post-nebulization, liposomes size was larger in the nebulizer reservoir in the range of 7.79±0.48 µm–9.73±1.53 µm for both powder and tablet formulations as compared to freshly prepared liposomes (5.38±0.73 µm–5.85±0.86 µm), suggesting liposome aggregation/fusion in the nebulizer’s reservoir. All formulations exhibited more than 80% mass output regardless of formulation type, but greater BDP proportions (circa 50%) were delivered to the Two-stage Impinger when tablet formulations were used. Moreover, the nebulized droplet median size and size distribution were lower for all tablet formulations in comparison to the powder formulations. Proliposome tablet and powdered formulations demonstrated the ability to generate vesicles that sustained the release of BDP.

Conclusion

Overall, this study showed that proliposome tablets could be disintegrated within a Pari-LC Sprint nebulizer to generate inhalable aerosol, with high drug output and hence can be manufactured on large scale to overcome the storage problems associated with powder formulations.