Encapsulation of Nicardipine Hydrochloride and Release from Biodegradable Poly(D,L-lactic-co-glycolic acid) Microparticles by Double Emulsion Process: Effect of Emulsion Stability and Different Parameters on Drug Entrapment

Lipid-Polymer Hybrid Nanoparticles Synthesized via Lipid-Based Surface Engineering for a robust drug delivery platform

Herein, lipid-polymer core-shell hybrid nanoparticles composed of poly(D,L-lactic-co-glycolic acid) (PLGA)/lecithin (PLNs) were synthesized through lipid-based surface engineering. Lipids were absorbed onto the surface of the PLGA core to enhance the advantages of polymeric nanoparticles and liposomes. The amounts of lipids and encapsulation of the drug nicardipine hydrochloride (NCH) in the PLNs were studied. NCH-loaded PLNs (NCH-PLNs) were produced in high yield (66%) with a high encapsulation efficiency (92%) and a size of 176 nm. The mass of phosphorus (P) on the NCH-PLN surface was qualitatively and quantitatively investigated using X-ray fluorescence spectroscopy, and lecithin addition increased the P mass percentage due to the phosphate group (PO43-) in its structure. These data confirmed the lipid-based surface engineering of NCH-PLNs. The zeta potential of NCH-PLN exceeded -30 mV, ensuring colloidal stability, and preventing precipitation through electrostatic stabilization. In vitro, NCH was continuously and slowly released from NCH-PLNs over 16 days. Furthermore, PSVK1 cells exhibited high viability after treatment with NCH-PLNs, indicating favorable cytocompatibility. After comparing various mathematical equations of drug release kinetics, the data best fit the Korsmeyer-Peppas model with R2 values of 0.989, 0.990, and 0.982 for 1.0, 3.0, and 5.0 mg/mL lecithin, respectively. The release exponents obtained ranged from 0.480 to 0.505, suggesting anomalous transport release. Thus, NCH-PLNs have potential as a robust drug delivery platform for the controlled administration of NCH, particularly for vasodilation during neurosurgery.

Preparation, Optimization, and In-Vitro Evaluation of Brusatol- and Docetaxel-Loaded Nanoparticles for the Treatment of Prostate Cancer

Challenges to docetaxel use in prostate cancer treatment include several resistance mechanisms as well as toxicity. To overcome these challenges and to improve the therapeutic efficacy in heterogeneous prostate cancer, the use of multiple agents that can destroy different subpopulations of the tumor is required. Brusatol, a multitarget inhibitor, has been shown to exhibit potent anticancer activity and play an important role in drug response and chemoresistance. Thus, the combination of brusatol and docetaxel in a nanoparticle platform for the treatment of prostate cancer is expected to produce synergistic effects. In this study, we reported the development of polymeric nanoparticles for the delivery of brusatol and docetaxel in the treatment of prostate cancer. The one-factor-at-a-time method was used to screen for formulation and process variables that impacted particle size. Subsequently, factors that had modifiable effects on particle size were evaluated using a 24 full factorial statistical experimental design followed by the optimization of drug loading. The optimization of blank nanoparticles gave a formulation with a mean size of 169.1 nm ± 4.8 nm, in agreement with the predicted size of 168.333 nm. Transmission electron microscopy showed smooth spherical nanoparticles. The drug release profile showed that the encapsulated drugs were released over 24 h. Combination index data showed a synergistic interaction between the drugs. Cell cycle analysis and the evaluation of caspase activity showed differences in PC-3 and LNCaP prostate cancer cell responses to the agents. Additionally, immunoblots showed differences in survivin expression in LNCaP cells after treatment with the different agents and formulations for 24 h and 72 h. Therefore, the nanoparticles are potentially suitable for the treatment of advanced prostate cancer.

Nose-to-brain delivery of hesperidin nanoparticles loaded in-situ gel for neuroprotective action

OBJECTIVE

Major depressive disorder (also known as depression) is a serious mental health condition that has a detrimental impact on a person's mood, thoughts, and behaviour. The presence of oxidative stress is associated with an increased risk of developing depression. A flavonoid called hesperidin (HSP) has been proven to be helpful in experimental depression because of its powerful antioxidant properties. However, due to its limited bioavailability, gastro-intestinal degradation, inadequate permeability, and low water solubility, the clinical development of HSP has been impeded. The objective of the present research was to develop HSP nanoparticles (NPs) loaded in-situ gel for nose-to-brain delivery to provide neuroprotective action.

MATERIAL AND METHODS

HSP NPs were prepared by nanoprecipitation technique and were tailored to the size by using ultrasonication technique. Optimisation of NPs was conducted using the central composite design. Prepared particles were analysed by Fourier transformed infrared spectroscopy (FTIR), DSC, and UV technique. Forced swim test was conducted as a behavioural assessment to gauze the neuroprotective antidepressant activity of the prepared formulation.

RESULTS

The particle size was found to be in the range of 76.5±0.86nm to 239.2+0.31nm, zeta potential in the range of -8.37±0.6mV to 22.4±1.37mV, and entrapment efficiency in the range of 54.92±1.36% to 74.53±1.28%. Pharmacodynamic study showed formulation significantly decreased the immobility time in experimental animals.

CONCLUSION

This study showed the potential of HSP NPs to be an effective neuroprotective agent.

Use of low-field NMR and rheology to evaluate the microstructure and stability of a poly(d,l-lactide-co-glycolide)-based W/O emulsion to be processed by spray drying

Drug-loaded emulsions for spray drying should be optimised for their rheological behaviour and stability under operating conditions, as this is essential for achieving the desired physicochemical properties of the final dry product. Our aim was therefore to investigate the structure and stability of a water-in-oil (W/O) emulsion containing vancomycin hydrochloride as the active ingredient in the aqueous phase, poly(d,l-lactide-co-glycolide) as the structural polymer in the dichloromethane-based organic phase, and various stabilisers using low-field nuclear magnetic resonance (LF NMR) and rheological characterisation. Four emulsions were tested, namely-one without stabiliser, one with Poloxamer® 407, one with chitosan and Span™ 80 and one with chitosan only. The theoretical interpretation of the rheological data allowed the determination of the velocity and the shear rate/stress profiles inside the feed path of the W/O emulsion, aspects that are critical for the industrial scale-up of the emulsion drying process. In addition, LF NMR demonstrated that shaking was sufficient to restore the original emulsion structure and that the droplet size of all emulsions was in the range of 1-10 μm, although the emulsion with chitosan had the narrowest droplet size distribution and the higher zero shear viscosity, which accounts for the increased long-term stability due to impeded droplets movement.

Biocatalytic self-assembled synthetic vesicles and coacervates: From single compartment to artificial cells

Compartmentalization is an intrinsic feature of living cells that allows spatiotemporal control over the biochemical pathways expressed in them. Over the years, a library of compartmentalized systems has been generated, which includes nano to micrometer sized biomimetic vesicles derived from lipids, amphiphilic block copolymers, peptides, and nanoparticles. Biocatalytic vesicles have been developed using a simple bag containing enzyme design of liposomes to multienzymes immobilized multi-vesicular compartments for artificial cell generation. Additionally, enzymes were also entrapped in membrane-less coacervate droplets to mimic the cytoplasmic macromolecular crowding mechanisms. Here, we have discussed different types of single and multicompartment systems, emphasizing their recent developments as biocatalytic self-assembled structures using recent examples. Importantly, we have summarized the strategies in the development of the self-assembled structure to improvise their adaptivity and flexibility for enzyme immobilization. Finally, we have presented the use of biocatalytic assemblies in mimicking different aspects of living cells, which further carves the path for the engineering of a minimal cell.

Macromolecular design and preparation of polymersomes

From drug delivery to nanoreactors and protocells, polymersomes have gained considerable interest from researchers due to their novel applications.

Biodegradable synthetic polyesters in the technology of controlled dosage forms of antihypertensive drugs - the overview

Introduction: Arterial hypertension is a disease of civilization that requires long-term treatment. Recently, growing interest in natural and synthetic polymers as drug delivery vehicles in controlled release dosage forms for improving the efficacy of treatment has been observed. Areas covered: This review introduces biodegradable synthetic polyesters as macromolecular carriers of antihypertensive drugs. Although various, synthetic and natural polymer-drug conjugates and/or polymeric carriers of anticancer drugs are currently under preclinical and clinical studies, there is no such data for antihypertensive drugs. Therefore, it seems appropriate to use such materials for the treatment of hypertension. Expert opinion: There are currently only a few studies describing the use of synthetic polyesters in the arterial hypertension therapy. In order to the fact that there is a high demand for new, effective antihypertensive dosage forms, further studies for such drug carriers are certainly expected. Synthetic polyester carriers could improve the drug bioavailability and its pharmacokinetic properties by altering the pharmaceutical dosage form. This property is particularly useful for drugs with proven pharmacological action, but with limited application due to their inappropriate pharmacological properties. The development of new polymeric materials and technologies affords the opportunity to produce novel synthetic polyester DDSs.