Development and evaluation of polyvinyl alcohol stabilized polylactide-co-caprolactone-based nanoparticles for brain delivery

Therapeutic Effects of Nanocoating of Apitoxin (Bee Venom) and Polyvinyl Alcohol Supplemented with Zinc Oxide Nanoparticles

Background/Objectives: Bee venom (BV), as a natural product, is one of the foundations of the pharmaceutical industry, through which many diseases, including serious ones, can be effectively treated. The BV nanofilm is an effective antidote delivered into the human body to target the affected area and address the issue without major side effects. In this study, we investigated the intriguing therapeutic effects of apitoxin (bee venom) used in isolation, combined with the powerful properties of zinc oxide nanoparticles. Methods and Results: BV nanofilm was evaluated using Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD). The BV extract was analyzed using mass spectrometry (MS), which identified 84 active components present at varying concentrations. BV was treated with both polyvinyl alcohol (PVA) and zinc oxide nanoparticles (ZNPs) to increase the intensity of OH and CH2 groups and to enhance the dispersion of C=O. BV has demonstrated anti-type 2 diabetes activity by inhibiting α-amylase and α-glucosidase, which are starch-degrading enzymes. The nanofilm is an active mixture of BV, PVA, and ZNPs, which exhibited the highest antidiabetic activity with IC50 values of 30.33 μg/mL and 5.55 μg/mL for the inhibition of α-amylase and α-glucosidase, compared to IC50 of 51.69 µg/mL and IC50 of 7.30 µg/mL for BV, respectively. The nanofilm also showed higher anti-inflammatory activity by inhibiting red blood cell (RBC) hemolysis, with an IC50 of 16.99 μg/mL in comparison to IC50 of 72.99 µg/mL for BV alone. The nanofilm demonstrated broad-spectrum antimicrobial activity, effectively targeting both Gram-positive (Staphylococcus aureus ATCC 6538 and Bacillus subtilis ATCC 6633) and Gram-negative bacteria (Salmonella typhi ATCC 6539, Escherichia coli ATCC 8739). Furthermore, increased antioxidant activity was recorded by inhibiting the 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging effect with an IC50 of 4.26 μg/mL and 19.43 μg/mL for nanofilm and BV, respectively. BV was found to be more toxic to liver tissue (HepG2 cell line) than nanofilm, with IC50 values of 18.5 ± 0.08 μg/mL and 52.27 ± 0.7 μg/mL, respectively. The BV extract displayed higher toxicity to liver tissue (2.3%) with 97.7% viability at 250 μg/mL, compared to nanofilm, which showed 0.09% toxicity and 99.9% viability at the same concentration. Conclusions: the BV nanofilm emerges as a promising alternative medicine, offering an innovative solution for treating various diseases through its high concentration of therapeutically active compounds and effortless targeting delivery.

PLGA Nanoparticles Based Mucoadhesive Nasal In Situ Gel for Enhanced Brain Delivery of Topiramate

Oral Topiramate therapy is associated with systemic adverse effects including paresthesia,abdominal pain, and fluctuations in plasma levels. The purpose of this research was to develop an intranasal in situ gel based system comprising Topiramate polymeric nanoparticles and evaluate its potential both in vitro and in vivo. Poly (lactic-co-glycolic acid) (PLGA)nanoparticles prepared by nanoprecipitation method were added into the in situ gelling system of Poloxamer 407 and HPMC K4M. Selected formulation (TG5) was evaluated for physicochemical properties, nasal permeation and in vivo pharmacokinetics in rats. PLGAnanoparticles (O1) exhibited low particle size (~ 144.4 nm), good polydispersity index (0.202), negative zeta potential (-12.7 mV), and adequate entrapment efficiency (64.7%). Developed in situ gel showed ideal pH (6.5), good gelling time (35 s), gelling temperature(37℃), suitable viscosity (1335 cP)and drug content of 96.2%. In vitro drug release conformedto Higuchi release kinetics, exhibiting a biphasic pattern of initial burst release and sustained release for 24 h. Oral administration of the drug to Sprague-Dawley rats (G3) showed higher plasma Cmax(504 ng/ml, p < 0.0001) when compared to nasal delivery of in situ gel (G4) or solution (G5). Additionally, AUC0-α of G3 (8786.82 ng/ml*h) was considerably higher than othergroups. Brain uptake data indicates a higher drug level with G4 (112.47 ng /ml) at 12 h when compared to G3. Histopathological examination of groups; G1 (intranasal saline), G2(intranasal placebo), G3, G4, and G5 did not show any lesions of pathological significance. Overall, the experimental results observed were promising and substantiated the potential of developed in situ gel for intranasal delivery.

Fabrication of porous poly(L-lactide-co-ε-caprolactone) micropowder for microbubble effect and ultrasound-mediated drug delivery

Biodegradable elastic poly(L-lactide-co-ε-caprolactone) (PLCL) copolymer (50:50, lactide:caprolactone molar ratio) was synthesized and porous PLCL micropowders was fabricated by a simple method involving rapid cooling of 0.1, 0.5, and 1% (wt/vol) PLCL/dioxane spray into liquid nitrogen. The physicochemical properties of the porous PLCL micropowders were examined by measuring their pore size, pore morphology, and microbead size using a scanning electron microscopy (SEM) and dye and temozolomide (TMZ)-release testing under ultrasound. Human U-87MG, glioblastoma (GBM) cell culture tests were performed to evaluate cell cytotoxicity by released drug from PLCL micropowders. In this study, the porous PLCL micropowders prepared from 1 wt%/vol% PLCL solutions showed a highly porous structure, satisfactory mechanical properties, and optimal drug release efficiency compared with those produced from 0.1 or 0.5 wt%/vol% solutions. The results of the accumulated release test with the results of the absorbance of the dye initially applied, it was confirmed that more than 80% of the added dye was trapped inside the micropowder, and clearly GBM cytotoxicity effect could be observed by the released TMZ. The drug release system using micropowders and ultrasound can be applied as a drug supply system for various diseases such as brain tumors with low drug permeability.

Molecularly Imprinted Drug Carrier for Lamotrigine-Design, Synthesis, and Characterization of Physicochemical Parameters

This study presents the initial attempt at introducing a magnetic molecularly imprinted polymer (MIP) designed specifically for lamotrigine with the purpose of functioning as a drug carrier. First, the composition of the magnetic polymer underwent optimization based on bulk polymer adsorption studies and theoretical analyses. The magnetic MIP was synthesized from itaconic acid and ethylene glycol dimethacrylate exhibiting a drug loading capacity of 3.4 ± 0.9 μg g-1. Structural characterization was performed using powder X-ray diffraction analysis, vibrating sample magnetometry, and Fourier transform infrared spectroscopy. The resulting MIP demonstrated controlled drug released characteristics without a burst effect in the phospahe buffer saline at pH 5 and 8. These findings hold promise for the potential nasal administration of lamotrigine in future applications.

Emerging strategies to fabricate polymeric nanocarriers for enhanced drug delivery across blood-brain barrier: An overview

Blood-brain barrier (BBB) serves as an essential interface between central nervous system (CNS) and its periphery, allowing selective permeation of ions, gaseous molecules, and other nutrients to maintain metabolic functions of brain. Concurrently, it restricts passage of unsolicited materials from bloodstream to CNS which could otherwise lead to neurotoxicity. Nevertheless, in the treatment of neurodegenerative diseases such as Parkinson's, Alzheimer's, diffuse intrinsic pontine glioma, and other brain cancers, drugs must reach CNS. Among various materials developed for this purpose, a few judiciously selected polymeric nanocarriers are reported to be highly prospective to facilitate BBB permeation. However, the challenge of transporting drug-loaded nanomaterials across this barrier remains formidable. Herein a concise analysis of recently employed strategies for designing polymeric nanocarriers to deliver therapeutics across BBB is presented. Impacts of 3Ss, namely, size, shape, and surface charge of polymeric nanocarriers on BBB permeation along with different ligands used for nanoparticle surface modification to achieve targeted delivery have been scrutinized. Finally, we elucidated future research directions in the context of designing smart polymeric nanocarriers for BBB permeation. This work aims to guide researchers engaged in polymeric nanocarrier design, helping them navigate where to begin, what challenges to address, and how to proceed effectively.

Cyclodextrin Stabilized Freeze-Dried Silica/Chitosan Nanoparticles for Improved Terconazole Ocular Bioavailability

This research assesses the beneficial effects of loading terconazole, a poorly water-soluble antifungal drug in silica/chitosan nanoparticles (SCNs) for ocular delivery. Nanoparticles were fabricated by the simple mixing of tetraethyl ortho silicate (TEOS) and chitosan HCl as sources of silica and nitrogen, respectively, along with alcoholic drug solution in different concentrations. Freeze-dried nanoparticles were fabricated using cyclodextrins as cryoprotectants. SCNs were assessed for their particle size, PDI, yield, drug loading and in vitro release studies. A 2³.3¹ full factorial experimental design was constructed to optimize the prepared SCNs. DSC, XRD, FTIR, in addition to morphological scanning were performed on the optimized nanoparticles followed by an investigation of their pharmacokinetic parameters after topical ocular application in male Albino rabbits. The results reveal that increasing the water content in the preparations causes an increase in the yield and size of nanoparticles. On the other hand, increasing the TEOS content in the preparations, caused a decrease in the yield and size of nanoparticles. The optimized formulation possessed excellent mucoadhesive properties with potential safety concerning the investigated rabbit eye tissues. The higher C_max and AUC_0–24 values coupled with a longer t_max value compared to the drug suspension in the rabbits’ eyes indicated the potential of SCNs as promising ocular carriers for poorly water-soluble drugs, such as terconazole.