Optimization, Characterization and Pharmacokinetic Study of Meso-Tetraphenylporphyrin Metal Complex-Loaded PLGA Nanoparticles

Is it advantageous to use quality by design (QbD) to develop nanoparticle-based dosage forms for parenteral drug administration?

Parenteral administration is one of the most commonly used drug delivery routes for nanoparticle-based dosage forms, such as lipid-based and polymeric nanoparticles. For the treatment of various diseases, parenteral administration include intravenous, subcutaneous, and intramuscular route. In drug development phase, multiparameter strategy with a focus on drug physicochemical properties and the specificity of the administration route is required. Nanoparticle properties in terms of size and targeted delivery, among others, are able to surpass many drawbacks of conventional dosage forms, but these unique properties can be a bottleneck for approval by regulatory authorities. Quality by Design (QbD) approach has been widely utilized in development of parenteral nanoparticle-based dosage forms. It fosters knowledge of product and process quality by involving sound scientific data and risk assessment strategies. A full and comprehensive investigation into the state of implementation and applications of the QbD approach in these complex drug products can highlight the gaps and challenges. In this review, the analysis of critical attributes and Design of Experiment (DoE) approach in different nanoparticulate systems, together with the proper utilization of Process Analytical Technology (PAT) applications are described. The essential of QbD approach for the design and development of nanoparticle-based dosage forms for delivery via parenteral routes is discussed thoroughly.

Antimicrobial Photodynamic Therapy Using Encapsulated Protoporphyrin IX for the Treatment of Bacterial Pathogens

Herein, we report on the antimicrobial photodynamic effect of polymeric nanoparticles containing the endogenous photosensitizer protoporphyrin IX. Compared to equivalent doses of the free photosensitizer, we demonstrated that the photodynamic antimicrobial efficacy of PLGA (polylactic-co-glycolic acid) nanoparticles containing protoporphyrin IX (PpIX) against pathogenic Staphylococcus aureus (S. aureus) is preserved after encapsulation, while photobleaching is reduced. In addition, compared to equivalent doses of the free porphyrin, we show that a reduction in the cytotoxicity in mammalian cell cultures is observed when encapsulated. Therefore, the encapsulation of protoporphyrin IX reduces its photodegradation, while the released photosensitizer maintains its ability to generate reactive oxygen species upon light irradiation. The polymeric nanoencapsulation promotes aqueous solubility for the hydrophobic PpIX, improves its photostability and reduces the cytotoxicity, while providing an extended release of this endogenous photosensitizer.

Thymol-Modified Oleic and Linoleic Acids Encapsulated in Polymeric Nanoparticles: Enhanced Bioactivity, Stability, and Biomedical Potential

Unsaturated fatty acids, such as oleic acid (OA) and linoleic acid (LA), are promising antimicrobial and cytostatic agents. We modified OA and LA with thymol (TOA and TLA, respectively) to expand their bioavailability, stability, and possible applications, and encapsulated these derivatives in polymeric nanoparticles (TOA-NPs and TLA-NPs, respectively). Prior to synthesis, we performed mathematical simulations with PASS and ADMETlab 2.0 to predict the biological activity and pharmacokinetics of TOA and TLA. TOA and TLA were synthesized via esterification in the presence of catalysts. Next, we formulated nanoparticles using the single-emulsion solvent evaporation technique. We applied dynamic light scattering, Uv-vis spectroscopy, release studies under gastrointestinal (pH 1.2-6.8) and blood environment simulation conditions (pH 7.4), and in vitro biological activity testing to characterize the nanoparticles. PASS revealed that TOA and TLA have antimicrobial and anticancer therapeutic potential. ADMETlab 2.0 provided a rationale for TOA and TLA encapsulation. The nanoparticles had an average size of 212-227 nm, with a high encapsulation efficiency (71-93%), and released TOA and TLA in a gradual and prolonged mode. TLA-NPs possessed higher antibacterial activity against B. cereus and S. aureus and pronounced cytotoxic activity against MCF-7, K562, and A549 cell lines compared to TOA-NPs. Our findings expand the biomedical application of fatty acids and provide a basis for further in vivo evaluation of designed derivatives and formulations.

Radiolabeling of Micro-/Nanoplastics via In-Diffusion

Micro- and nanoplastics are emerging pollutants with a concerning persistence in the environment. Research into their environmental impact requires addressing challenges related to sensitively and selectively detecting them in complex ecological media. One solution with great potential for alleviating these issues is using radiolabeling strategies. Here, we report the successful introduction of a 64Cu radiotracer into common microplastics, namely polyethylene, polyethylene terephthalate, polystyrene, polyamide, and polyvinylidene dichloride, which allows the sensitive detection of mere nanograms of substance. Utilizing a Hansen Solubility Parameter screening, we developed a swelling and in-diffusion process for tetraphenylporphyrin-complexed 64Cu, which permits one-pot labeling of polymer particles.

Effect of Electrospun PLGA/Collagen Scaffolds on Cell Adhesion, Viability, and Collagen Release: Potential Applications in Tissue Engineering

The development of scaffolding obtained by electrospinning is widely used in tissue engineering due to porous and fibrous structures that can mimic the extracellular matrix. In this study, poly (lactic-co-glycolic acid) (PLGA)/collagen fibers were fabricated by electrospinning method and then evaluated in the cell adhesion and viability of human cervical carcinoma HeLa and NIH-3T3 fibroblast for potential application in tissue regeneration. Additionally, collagen release was assessed in NIH-3T3 fibroblasts. The fibrillar morphology of PLGA/collagen fibers was verified by scanning electron microscopy. The fiber diameter decreased in the fibers (PLGA/collagen) up to 0.6 µm. FT-IR spectroscopy and thermal analysis confirmed that both the electrospinning process and the blend with PLGA give structural stability to collagen. Incorporating collagen in the PLGA matrix promotes an increase in the material's rigidity, showing an increase in the elastic modulus (38%) and tensile strength (70%) compared to pure PLGA. PLGA and PLGA/collagen fibers were found to provide a suitable environment for the adhesion and growth of HeLa and NIH-3T3 cell lines as well as stimulate collagen release. We conclude that these scaffolds could be very effective as biocompatible materials for extracellular matrix regeneration, suggesting their potential applications in tissue bioengineering.

Box-Behnken assisted development and validation of high-performance liquid chromatography method for the simultaneous determination of doxorubicin and vorinostat in polymeric nanoparticles

While histone deacetylase inhibitors, such as vorinostat, demonstrate a significant effect against hematological cancers, their application for solid tumor treatment is limited. However, there is strong evidence that combinatorial administration of vorinostat and genotoxic agents (e.g., doxorubicin) enhances the antitumoral action of both drugs against tumors. We developed a high-performance liquid chromatography method for the simultaneous determination of doxorubicin and vorinostat in polymeric nanoparticles designed to provide the parenteral administration of both drugs and increase their safety profile. We performed separation on Nucleodur C-18 Gravity column with a mixture of 10 mM potassium dihydrogen phosphate buffer pH 3.9:ACN (90:10 v/v) as mobile phase at 240 nm. The method was linear within the concentration range of 4.2-52.0 μg/ml for both drugs with limits of detection and quantification of 3.5 and 10.7 μg/ml for doxorubicin and 2.5 and 7.7 μg/ml for vorinostat, respectively. The method was precise and accurate over the concentration range of analysis. Drug loading was 5.4% for doxorubicin and 0.8% for vorinostat. Degradation of doxorubicin after irradiation was less than 5%, while the amount of vorinostat decreased at 88% under the same conditions. Thus, the validated method could be adopted for routine simultaneous analysis of doxorubicin and vorinostat in polymeric nanoparticles.

Fluoroplast Doped by Ag2O Nanoparticles as New Repairing Non-Cytotoxic Antibacterial Coating for Meat Industry

Foodborne infections are an important global health problem due to their high prevalence and potential for severe complications. Bacterial contamination of meat during processing at the enterprise can be a source of foodborne infections. Polymeric coatings with antibacterial properties can be applied to prevent bacterial contamination. A composite coating based on fluoroplast and Ag₂O NPs can serve as such a coating. In present study, we, for the first time, created a composite coating based on fluoroplast and Ag₂O NPs. Using laser ablation in water, we obtained spherical Ag₂O NPs with an average size of 45 nm and a ζ-potential of -32 mV. The resulting Ag₂O NPs at concentrations of 0.001-0.1% were transferred into acetone and mixed with a fluoroplast-based varnish. The developed coating made it possible to completely eliminate damage to a Teflon cutting board. The fluoroplast/Ag₂O NP coating was free of defects and inhomogeneities at the nano level. The fluoroplast/Ag₂O NP composite increased the production of ROS (H₂O₂, OH radical), 8-oxogualnine in DNA in vitro, and long-lived active forms of proteins. The effect depended on the mass fraction of the added Ag₂O NPs. The 0.01-0.1% fluoroplast/NP Ag₂O coating exhibited excellent bacteriostatic and bactericidal properties against both Gram-positive and Gram-negative bacteria but did not affect the viability of eukaryotic cells. The developed PTFE/NP Ag₂O 0.01-0.1% coating can be used to protect cutting boards from bacterial contamination in the meat processing industry.

Nanoformulation of Paclitaxel: Exploring the Cyclodextrin / PLGA Nano Delivery Carrier to Slow Down Paclitaxel Release, Enhance Accumulation in Vivo

Background: Improving the aggregation and penetration in tumor sites increases the anti-tumor efficacy of nanomedicine. In the current study, we designed cyclodextrin modified PLGA nanoparticles loaded with paclitaxel to elevate the accumulation and prolong circulation of chemotherapy drugs in vivo. Methods: The PLGA nanoparticles loaded with paclitaxel (PTX PLGA NPs) and cyclodextrin (CD) modified PLGA nanoparticles loaded with paclitaxel (PTX PLGA/CD NPs) were prepared using the emulsification solvent evaporation method. The nanoparticles were characterized by particle size, zeta potential, encapsulation efficiency, infrared spectroscopy analysis and X-Ray diffraction (XRD). Then, drug release of the nanoparticles was evaluated via reverse dialysis method in vitro. Finally, the in vivo distribution fate and pharmacokinetic characteristics of the nanoparticles were assessed in mice and rats. Results: The average particle size, zeta potential, and encapsulation efficiency of PTX PLGA NPs were (163.57±2.07) nm, - (20.53±2.79) mV and (60.44±6.80)%. The average particle size, zeta potential, and encapsulation efficiency of PTX PLGA/CD NPs were (148.57±1.66) nm, - (11.42±0.84) mV and (85.70±2.06)%. In vitro release studies showed that PTX PLGA/CD NPs were released more slowly compared to PTX PLGA NPs under normal blood pH conditions, while PTX PLGA/CD NPs were released more completely under tumor site pH conditions. The modified PLGA nanocarrier (PLGA/CD NPs) increased drug residence time and accumulation than the plain PLGA nanocarrier (PLGA NPs) in vivo distribution. In addition, the elimination half-life, area under the drug-time curve, and maximum blood concentration of the nanoparticle group were higher than those of Taxol^®, especially the PTX PLGA/CD NPs group, which was significantly different from Taxol^® and plain nanoparticle groups (p<0.001). Conclusions: The 2-HP-β-CD modified PLGA nanoparticles prolonged circulation time and accumulation of the chemotherapy drug paclitaxel in vivo.

Synthesis, characterization, and evaluation of chloroaluminium phthalocyanine incorporated in poly(ε-caprolactone) nanoparticles for photodynamic therapy

BACKGROUND

The use of nanotechnology has been widely used in biomedical science, which consists of orthopedic implants, tissue engineering, cancer therapy and drug elution from nanoparticle systems, such as poly-caprolactone (PCL) nanoparticles, which stand out mainly for their biocompatibility, being considered as effective carriers for photosensitizing drugs (PS) in photodynamic therapy (PDT) protocols.

METHODS

This manuscript describes the synthesis and characterization of PCL nanoparticles for controlled release of the drug chloro-aluminum phthalocyanine (ClAlPc) as a photosensitizer for application in PDT. The PCL-ClAlPc nanoparticles were developed by the nanoprecipitation process. The structure and morphology of the nanoparticles were studied with scanning electron microscopy (SEM) and with Fourier transform infrared (FTIR). The size of nanomaterials was studied using the Dynamic Light Scattering (DLS) method. Photophysical and photochemical characterizations were performed. Subsequently, photobiological studies were also used to characterize the system.

RESULTS

The nanoparticles had an average diameter of 384.7 ± 138.6 nm and a polydispersity index of 0.153. SEM analysis revealed that the system formed a spherical shape typical of these delivery systems. Charging efficiency was 82.1% ± 1.2%. The phthalocyanine-loaded PCL nanoparticles maintained their photophysical behavior after encapsulation. Cell viability was determined after the dark toxicity test, and it was possible to observe that there was no evidence of toxicity in the dark, for all concentrations tested. The assay also revealed that adenocarcinoma cells treated with free ClAlPc and in the nanoformulation showed 100% cell death when subjected to PDT protocols. The intracellular location of the photosensitizer indicated a high potential for accumulation in the cytoplasm and nucleus.

CONCLUSIONS

From the photophysical, photochemical and photobiological analyzes obtained, it was possible to observe that the development of PCL nanoparticles encapsulated with ClAlPc, by the nanoprecipitation method was adequate and that the in vivo release study is efficient to reduce the release rate and attenuate the burst of PS loaded on PCL nanoparticles. The results reinforce that the use of this system as drug delivery systems is useful in PDT protocols.

Synergetic Enhancement of Tumor Double-Targeted MRI Nano-Probe

The conventional targeted delivery of chemotherapeutic and diagnostic agents utilizing nanocarriers is a promising approach for cancer theranostics. Unfortunately, this approach often faces hindered tumor access that decreases the therapeutic index and limits the further clinical translation of a developing drug. Here, we demonstrated a strategy of simultaneously double-targeting the drug to two distinct cites of tumor tissue: the tumor endothelium and cell surface receptors. We used fourth-generation polyamideamine dendrimers modified with a chelated Gd and functionalized with selectin ligand and alpha-fetoprotein receptor-binding peptide. According to the proposed strategy, IELLQAR peptide promotes the conjugate recruitment to the tumor inflammatory microenvironment and enhances extravasation through the interaction of nanodevice with P- and E-selectins expressed by endothelial cells. The second target moiety-alpha-fetoprotein receptor-binding peptide-enhances drug internalization into cancer cells and the intratumoral retention of the conjugate. The final conjugate contained 18 chelated Gd ions per dendrimer, characterized with a 32 nm size and a negative surface charge of around 18 mV. In vitro contrasting properties were comparable with commercially available Gd-chelate: r1 relaxivity was 3.39 for Magnevist and 3.11 for conjugate; r2 relaxivity was 5.12 for Magnevist and 4.81 for conjugate. By utilizing this dual targeting strategy, we demonstrated the increment of intratumoral accumulation, and a remarkable enhancement of antitumor effect, resulting in high-level synergy compared to monotargeted conjugates. In summary, the proposed strategy utilizing tumor tissue double-targeting may contribute to an enhancement in drug and diagnostic accumulation in aggressive tumors.

Long-Lasting Exendin-4-Loaded PLGA Nanoparticles Ameliorate Cerebral Ischemia/Reperfusion Damage in Diabetic Rats

Exendin-4 (Ex-4) is an incretin mimetic agent approved for diabetes treatment and neuronal protection. However, the required frequent injections restrict its clinical application. We prepared Ex-4-loaded poly(d,l-lactide-co-glycolide) nanoparticles (PEx-4) and investigated their effect on cerebral ischemia/reperfusion (IR) injury associated with micturition center damage-induced cystopathy in diabetic rats. Using ten minutes of bilateral carotid artery occlusion combined with hemorrhage-induced hypotension of the IR model in streptozotocin-induced type 1 diabetic (T1DM) Wistar rats, we compared the effects of Ex-4 and PEx-4 on prefrontal cortex edema, voiding function and oxidative stress including cerebral spinal fluid (CSF) reference H₂O₂ (RH₂O₂) and HOCl (RHOCl) levels, endoplasmic reticulum (ER) stress, apoptosis, autophagy and pyroptosis signaling in brain and bladder by Western blot and immunohistochemistry. Single injection of PEx-4 displayed higher CSF antioxidant activity and a long-lasting hypoglycemic effect compared to Ex-4 in rats. T1DM and IR primarily enhanced CSF RH₂O₂, and pIRE-1/caspase-12/pJNK/CHOP-mediated ER stress, caspase-3/PARP-mediated apoptosis, Beclin-1/LC3B-mediated autophagy and caspase-1/IL-1β-mediated pyroptosis signaling in the damaged brains. Our data further evidenced that PEx-4 were more efficient than Ex-4 in attenuating IR-evoked prefrontal cortex edema, the impairment in micturition center and the enhanced level of CSF RH₂O₂ and HOCl, ER stress, apoptosis, autophagy and pyroptosis parameters in the damaged brains, but had less of an effect on IR-induced voiding dysfunction in bladders of T1DM rats. In summary, PEx-4 with stronger antioxidant activity and long-lasting bioavailability may efficiently confer therapeutic efficacy to ameliorate IR-evoked brain damage through the inhibitory action on oxidative stress, ER stress, apoptosis, autophagy and pyroptosis signaling in diabetic rats.