Brain Delivery Of Nanoparticles Research Articles

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

The biodegradable polymer poly-ε-(D, l-lactide-co-caprolactone) (PLCL) can be used to produce nanoparticles with tailored release pattern. In this study; the anti-epileptic drug, lamotrigine, was loaded in PLCL nanoparticles stabilized using various molecular weights and concentrations of polyvinyl alcohol (PVA). The nanoparticles were prepared by emulsification solvent evaporation technique. Nanoparticles were characterized for their morphology, particle size (PS), Zeta potential (ZP), entrapment efficiency (EE), drug loading capacity (DLC), yield percentage (YP)-values and drug release pattern. Drug concentration in Albino rats’ blood and brain after intravenous injection of selected nanoparticles was also analyzed. Results indicated that PS, EE, DLC, YP and ZP-values for the PLCL nanoparticles decreased with increasing PVA concentration. Formulated nanoparticles using LPVA were stable under various storage conditions. Lamotrigine release from nanoparticles was sustained for nearly a week. The selected formulation showed significantly high drug concentration in the brain compared to that for oral conventional tablet. In conclusion; varying PVA concentration and molecular weight used to stabilized PLCL nanoparticles helped in providing versatile properties for designing nanoparticles with wide range of properties.

Novel cyclic peptides facilitating transcellular blood-brain barrier transport of macromolecules in vitro and in vivo

Brain delivery of nanoparticles and macromolecular drugs depends on blood-brain barrier (BBB)-permeable carriers. In this study, we searched for cyclic heptapeptides facilitating BBB permeation of M13 phages by phage library screening using a transcellular permeability assay with hCMEC/D3 cell monolayers, a human BBB model. The M13 phage, which is larger than macromolecular drugs and nanoparticles, served as a model macromolecule. The screen identified cyclic heptapeptide SLSHSPQ (SLS) as a human BBB-permeable peptide. The SLS-displaying phage (SLS-phage) exhibited improved permeation across the cell monolayer of monkey and rat BBB co-culture models. The SLS-phage internalized into hCMEC/D3 cells via macropinocytosis and externalized via the exosome excretion pathway. SLS-phage distribution into brain parenchyma was observed in mice after intravenous administration. Moreover, liposome permeated across the BBB as cyclic SLS peptide conjugates. In conclusion, the cyclic SLS heptapeptide is a novel carrier candidate for brain delivery of macromolecular drugs and nanoparticles.

Amphiphilic Endomorphin-1 Derivative Functions as Self-assembling Nanomedicine for Effective Brain Delivery.

Endomorphin-1 (Tyr-Pro-Trp-Phe-NH2, EM-1), an endogenous μ-opioid receptor ligand with strong antinociceptive activity, is not in clinical use because of its limited metabolic stability and membrane permeability. In this study, we develop a short-peptide self-delivery system for brain targets with the capability to deliver EM-1 without vehicle. Two amphiphilic EM-1 derivatives, C18-SS-EM1 and C18-CONH-EM1, were synthesized by attaching a stearyl moiety to EM-1 via a disulfide and amide bond, respectively. The amphiphilicity of EM-1 derivatives enabled self-assembling into nanoparticles for brain delivery. The study assessed morphology, circular dichroism, and metabolic stability of the formulations, as well as their pharmacodynamics and in vivo distribution, directly monitored by near-IR fluorescence imaging in mouse brains. In aqueous solution, the C18-SS-EM1 derivative self-assembled into spherical nanostructures with a diameter of 10-20 nm. Near-IR fluorescence analysis visualized the accumulation of the peptides in the brain. Importantly, the analgesic effect of C18-SS-EM1 nanoparticles was significantly stronger as compared to that of unmodified EM-1 or C18-CONH-EM1 nanoparticles. An in vitro release study demonstrated that self-assembled C18-SS-EM1 nanoparticles possessed reduction-responsive behavior. In summary, self-assembling C18-SS-EM1 nanoparticles, which integrate the advantages of lipidization, nanoscale characteristics and, labile disulfide bonds, represent a promising strategy for brain delivery of short peptides.

In vitro/in vivo evaluation of gamma-aminobutyric acid-loadedN,N-dimethylacrylamide-based pegylated polymeric nanoparticles for brain delivery to treat epilepsy

Objectives of this study were the delivery of gamma aminobutyric acid (GABA) into the brain by means of developing brain targeted, nanosized, non-toxic and biocompatible polymeric nanoparticles, and investigating their effectiveness in epilepsy. For this purpose, GABA conjugated N,N-dimethylacrylamide-based pegylated nanoparticles were designed and characterised for particle size, zeta potential, pH, morphology, DSC, XRD, FTIR, GABA quantification and in vitro release. Formulations showed smaller particle size, cationic zeta potential characteristic, possible GABA polymeric matrix interaction and prolonged release pattern. Brain responses were examined using epileptic rats. Both formulations prepared were found to increase latency of seizure, decrease ending time of convulsion, duration of severe convulsion and mortality rate significantly compared with GABA solution. When GABA concentration was measured in Stratum corsatum, there was no statistical difference between GABA solution and formulations. All findings suggested enhancement in all phases of seizures indicating efficient delivery of GABA into the brain via formulations.

Nanoparticles for Brain Delivery of Drugs: In <I>Vivo</I> Experiments and Mechanism of Blood-Brain Barrier Crossing

Nanoparticles for Brain Delivery of Drugs: In <I>Vivo</I> Experiments and Mechanism of Blood-Brain Barrier Crossing

Lipid-Drug-Conjugate (LDC) Nanoparticles as Novel Carrier System for the Hydrophilic Antitrypanosomal Drug Diminazenediaceturate

The objective of the present study was to incorporate the hydrophilic drug diminazenediaceturate at a high loading into lipid nanoparticles by creating nanoparticles from lipid-drug conjugates (LDC). IR and DSC data showed that the antitrypanosomal drug diminazene is able to react with fatty acids to form water-insoluble salts like diminazenedistearate and -dioleate. The salts could be transformed into nanoparticles using high-pressure homogenization technique, established for solid lipid nanoparticles (SLN). By using polysorbate 80 as surfactant, physically stable LDC nanoparticle dispersions of both salts could be obtained. The mean PCS diameters and polydispersity indices were 364 nm and 0.233 for diminazenedistearate and 442 nm and 0.268 for diminazenedioleate, respectively. Due to the composition of the LDC bulk materials, nanoparticles with a high drug load of 33% (w/w) were obtained even for this highly water-soluble drug diminazenediaceturate. The new carrier system of LDC nanoparticles overcomes one limitation of SLN, i.e. the limited loading capacity for hydrophilic drugs. Transforming water-soluble hydrophilic drugs into LDC and formation of nanoparticles allows prolonged drug release and targeting to specific sites by i.v. injection. These results provide a first basis of using LDC-polysorbate 80 nanoparticles for brain delivery of diminazene to treat second stage human African trypanosomiasis (HAT).