Effect of particle size on the biodistribution, toxicity, and efficacy of drug-loaded polymeric nanoparticles in chemoradiotherapy

Biogenic metallic nanoparticles: from green synthesis to clinical translation

Biogenic metallic nanoparticles (NPs) have garnered significant attention in recent years due to their unique properties and various applications in different fields. NPs, including gold, silver, zinc oxide, copper, titanium, and magnesium oxide NPs, have attracted considerable interest. Green synthesis approaches, utilizing natural products, offer advantages such as sustainability and environmental friendliness. The theranostics applications of these NPs hold immense significance in the fields of medicine and diagnostics. The review explores intricate cellular uptake pathways, internalization dynamics, reactive oxygen species generation, and ensuing inflammatory responses, shedding light on the intricate mechanisms governing their behaviour at a molecular level. Intriguingly, biogenic metallic NPs exhibit a wide array of applications in medicine, including but not limited to anti-inflammatory, anticancer, anti-diabetic, anti-plasmodial, antiviral properties and radical scavenging efficacy. Their potential in personalized medicine stands out, with a focus on tailoring treatments to individual patients based on these NPs' unique attributes and targeted delivery capabilities. The article culminates in emphasizing the role of biogenic metallic NPs in shaping the landscape of personalized medicine. Harnessing their unique properties for tailored therapeutics, diagnostics and targeted interventions, these NPs pave the way for a paradigm shift in healthcare, promising enhanced efficacy and reduced adverse effects.

Nanoparticles toxicity: an overview of its mechanism and plausible mitigation strategies

Over the last decade, nanoparticles have found great interest among scientists and researchers working in various fields within the realm of biomedicine including drug delivery, gene delivery, diagnostics, targeted therapy and biomarker mapping. While their physical and chemical properties are impressive, there is growing concern about the toxicological potential of nanoparticles and possible adverse health effects as enhanced exposure of biological systems to nanoparticles may result in toxic effects leading to serious contraindications. Toxicity associated with nanoparticles (nanotoxicity) may include the undesired response of several physiological mechanisms including the distressing of cells by external and internal interaction with nanoparticles. However, comprehensive knowledge of nanotoxicity mechanisms and mitigation strategies may be useful to overcome the hazardous situation while treating diseases with therapeutic nanoparticles. With the same objectives, this review discusses various mechanisms of nanotoxicity and provides an overview of the current state of knowledge on the impact of nanotoxicity on biological control systems and organs including liver, brain, kidneys and lungs. An attempt also been made to present various approaches of scientific research and strategies that could be useful to overcome the effect of nanotoxicity during the development of nanoparticle-based systems including coating, doping, grafting, ligation and addition of antioxidants.

On the uncertainty of the correlation between nanoparticle avidity and biodistribution

The specific delivery of a drug to its site of action also known as targeted drug delivery is a topic in the field of pharmaceutics studied for decades. One approach extensively investigated in this context is the use ligand functionalized nanoparticles. These particles are modified to carry receptor specific ligands, enabling them to accumulate at a desired target site. However, while this concept initially appears straightforward to implement, in-depth research has revealed several challenges hindering target site specific particle accumulation - some of which remain unresolved to this day. One of these challenges consists in the still incomplete understanding of how nanoparticles interact with biological systems. This knowledge gap significantly compromises the predictability of particle distribution in biological systems, which is critical for therapeutic efficacy. One of the most crucial steps in delivery is the attachment of nanoparticles to cells at the target site. This attachment occurs via the formation of multiple ligand receptor bonds. A process also referred to as multivalent interaction. While multivalency has been described extensively for individual molecules and macromolecules respectively, little is known on the multivalent binding of nanoparticles to cells. Here, we will specifically introduce the concept of avidity as a measure for favorable particle membrane interactions. Also, an overview about nanoparticle and membrane properties affecting avidity will be given. Thereafter, we provide a thorough review on literature investigating the correlation between nanoparticle avidity and success in targeted particle delivery. In particular, we want to analyze the currently uncertain data on the existence and nature of the correlation between particle avidity and biodistribution.

Liposomal nanoformulations with trans-caryophyllene and caryophyllene oxide: do they have an inhibitory action on the efflux pumps NorA, Tet(K), MsrA, and MepA?

This study aimed to evaluate the antibacterial and inhibitory action of NorA, Tet(K), MsrA and MepA efflux pumps in S. aureus strains using the sesquiterpenes named trans-caryophyllene and caryophyllene oxide, both isolated and encapsulated in liposomes. The antibacterial and inhibitory action of these efflux pumps was evaluated through the serial microdilution test in 96-well microplates. Each sesquiterpene and liposome/sesquiterpene was combined with antibiotics and ethidium bromide (EtBr). The antibiotics named norfloxacin, tetracycline and erythromycin were used. The 1199 B, IS-58, RN4220 and K2068 S. aureus strains carrying NorA, Tet(K), MsrA and MepA, respectively, were tested. In the fluorescence measurement test, K2068 S. aureus was incubated with the sesquiterpenes and EtBr, and the fluorescence emission by EtBr was measured. The tested substances did not show direct antibacterial activity, with MIC >1024 μg/mL. Nonetheless, the isolated trans-caryophyllene and caryophyllene oxide reduced the MIC of antibiotics and EtBr, indicating inhibition of NorA, Tet(K) and MsrA. In the fluorescence test, these same sesquiterpenes increased fluorescence emission, indicating inhibition of MepA. Therefore, the sesquiterpenes named trans-caryophyllene and caryophyllene oxide did not show direct antibacterial action; however, in their isolated form, they showed possible inhibitory action on NorA, Tet(K), MsrA and MepA efflux pumps. They may also act in antibiotic potentiation. Further studies are needed to identify the mechanisms involved in antibiotic potentiation and efflux pump inhibitory action.

A Holographic-Type Model in the Description of Polymer-Drug Delivery Processes

A unitary model of drug release dynamics is proposed, assuming that the polymer-drug system can be assimilated into a multifractal mathematical object. Then, we made a description of drug release dynamics that implies, via Scale Relativity Theory, the functionality of continuous and undifferentiable curves (fractal or multifractal curves), possibly leading to holographic-like behaviors. At such a conjuncture, the Schrödinger and Madelung multifractal scenarios become compatible: in the Schrödinger multifractal scenario, various modes of drug release can be "mimicked" (via period doubling, damped oscillations, modulated and "chaotic" regimes), while the Madelung multifractal scenario involves multifractal diffusion laws (Fickian and non-Fickian diffusions). In conclusion, we propose a unitary model for describing release dynamics in polymer-drug systems. In the model proposed, the polymer-drug dynamics can be described by employing the Scale Relativity Theory in the monofractal case or also in the multifractal one.

Metformin Loaded Zein Polymeric Nanoparticles to Augment Antitumor Activity against Ehrlich Carcinoma via Activation of AMPK Pathway: D-Optimal Design Optimization, In Vitro Characterization, and In Vivo Study

Metformin (MET), an antidiabetic drug, is emerging as a promising anticancer agent. This study was initiated to investigate the antitumor effects and potential molecular targets of MET in mice bearing solid Ehrlich carcinoma (SEC) as a model of breast cancer (BC) and to explore the potential of zein nanoparticles (ZNs) as a carrier for improving the anticancer effect of MET. ZNs were fabricated through ethanol injection followed by probe sonication method. The optimum ZN formulation (ZN8) was spherical and contained 5 mg zein and 30 mg sodium deoxycholate with a small particle size and high entrapment efficiency percentage and zeta potential. A stability study showed that ZN8 was stable for up to three months. In vitro release profiles proved the sustained effect of ZN8 compared to the MET solution. Treatment of SEC-bearing mice with ZN8 produced a more pronounced anticancer effect which was mediated by upregulation of P53 and miRNA-543 as well as downregulation of NF-κB and miRNA-191-5p gene expression. Furthermore, ZN8 produced a marked elevation in pAMPK and caspase-3 levels as well as a significant decrease in cyclin D1, COX-2, and PGE2 levels. The acquired findings verified the potency of MET-loaded ZNs as a treatment approach for BC.

Using particle dimensionality-based modeling to estimate lung carcinogenicity of 3D printer emissions

The use of 3D printing technologies by industry and consumers is expanding. However, the approaches to assess the risk of lung carcinogenesis from the emissions of 3D printers have not yet been developed. The objective of the study was to demonstrate a methodology for modeling lung cancer risk related to specific exposure levels as derived from an experimental study of 3D printer emissions for various types of filaments (ABS, PLA, and PETG). The emissions of 15 filaments were assessed at varying extrusion temperatures for a total of 23 conditions in a Class 1,000 cleanroom following procedures described by ANSI/CAN/UL 2904. Three approaches were utilized for cancer risk estimation: (a) calculation based on PM2.5 and PM10 concentrations, (b) a proximity assessment based on the pulmonary deposition fraction, and (c) modeling based on the mass-weighted aerodynamic diameter of particles. The combined distribution of emitted particles had the mass median aerodynamic diameter (MMAD) of 0.35 μm, GSD 2.25. The average concentration of PM2.5 was 25.21 μg/m3 . The spline-based function of aerodynamic diameter allowed us to reconstruct the carcinogenic potential of seven types of fine and ultrafine particles (crystalline silica, fine TiO2 , ultrafine TiO2 , ambient PM2.5 and PM10, diesel particulates, and carbon nanotubes) with a correlation of 0.999, P < 0.00001. The central tendency estimation of lung cancer risk for 3D printer emissions was found at the level of 14.74 cases per 10,000 workers in a typical exposure scenario (average cumulative exposure of 0.3 mg/m3 - years), with the lowest risks for PLA filaments, and the highest for PETG type.

Nanoengineered Polymeric RNA Nanoparticles for Controlled Biodistribution and Efficient Targeted Cancer Therapy

RNA nanotechnology, including rolling circle transcription (RCT), has gained increasing interest as a fascinating siRNA delivery nanoplatform for biostable and tumor-targetable RNA-based therapies. However, due to the lack of fine-tuning technologies for RNA nanostructures, the relationship between physicochemical properties and siRNA efficacy of polymeric siRNA nanoparticles (PRNs) with different sizes has not yet been fully elucidated. Herein, we scrutinized the effects of size/surface chemistry-tuned PRNs on the biological and physiological interactions with tumors. PRNs with adjusted size and surface properties were prepared using sequential engineering processes: RCT, condensation, and nanolayer deposition of functional biopolymers. Through the RCT process, nanoparticles of three sizes with a diameter of 50-200 nm were fabricated and terminated with three types of biopolymers: poly-l-lysine (PLL), poly-l-glutamate (PLG), and hyaluronic acid (HA) for different surface properties. Among the PRNs, HA-layered nanoparticles with a diameter of ∼200 nm exhibited the most effective systemic delivery, resulting in superior anticancer effects in an orthotopic breast tumor model due to the CD44 receptor targeting and optimized nanosized structure. Depending on the type of PRNs, the in vivo siRNA delivery with protein expression inhibition differed by up to approximately 20-fold. These findings indicate that the types of layered biopolymers and the PRNs size mediate efficient polymeric siRNA delivery to the targeted tumors, resulting in high RNAi-induced therapeutic efficacy. This RNA-nanotechnology-based size/surface editing can overcome the limitations of siRNA therapeutics and represents a potent built-in module method to design RNA therapeutics tailored for targeted cancer therapy.

Recent developments in the use of nanocrystals to improve bioavailability of APIs

Nanocrystals refer to materials with at least one dimension smaller than 100 nm, composing of atoms arranged in single crystals or polycrystals. Nanocrystals have significant research value as they offer unique advantages over conventional pharmaceutical formulations, such as high bioavailability, enhanced targeting selectivity and controlled release ability and are therefore suitable for the delivery of a wide range of drugs such as insoluble drugs, antitumor drugs and genetic drugs with broad application prospects. In recent years, research on nanocrystals has been progressively refined and new products have been launched or entered the clinical phase of studies. However, issues such as safety and stability still stand that need to be addressed for further development of nanocrystal formulations, and significant gaps do exist in research in various fields in this pharmaceutical arena. This paper presents a systematic overview of the advanced development of nanocrystals, ranging from the preparation approaches of nanocrystals with which the bioavailability of poorly water-soluble drugs is improved, critical properties of nanocrystals and associated characterization techniques, the recent development of nanocrystals with different administration routes, the advantages and associated limitations of nanocrystal formulations, the mechanisms of physical instability, and the enhanced dissolution performance, to the future perspectives, with a final view to shed more light on the future development of nanocrystals as a means of optimizing the bioavailability of drug candidates. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology.

Impact of the physical-chemical properties of poly(lactic acid)-poly(ethylene glycol) polymeric nanoparticles on biodistribution

Nanoparticle (NP) formulations are inherently polydisperse making their structural characterization and justification of specifications complex. It is essential, however, to gain an understanding of the physico-chemical properties that drive performance in vivo. To elucidate these properties, drug-containing poly(lactic acid) (PLA)-poly(ethylene glycol) (PEG) block polymeric NP formulations (or PNPs) were sub-divided into discrete size fractions and analyzed using a combination of advanced techniques, namely cryogenic transmission electron microscopy, small-angle neutron and X-ray scattering, nuclear magnetic resonance, and hard-energy X-ray photoelectron spectroscopy. Together, these techniques revealed a uniquely detailed picture of PNP size, surface structure, internal molecular architecture and the preferred site(s) of incorporation of the hydrophobic drug, AZD5991, properties which cannot be accessed via conventional characterization methodologies. Within the PNP size distribution, it was shown that the smallest PNPs contained significantly less drug than their larger sized counterparts, reducing overall drug loading, while PNP molecular architecture was critical in understanding the nature of in vitro drug release. The effect of PNP size and structure on drug biodistribution was determined by administrating selected PNP size fractions to mice, with the smaller sized NP fractions increasing the total drug-plasma concentration area under the curve and reducing drug concentrations in liver and spleen, due to greater avoidance of the reticuloendothelial system. In contrast, administration of unfractionated PNPs, containing a large population of NPs with extremely low drug load, did not significantly impact the drug's pharmacokinetic behavior - a significant result for nanomedicine development where a uniform formulation is usually an important driver. We also demonstrate how, in this study, it is not practicable to validate the bioanalytical methodology for drug released in vivo due to the NP formulation properties, a process which is applicable for most small molecule-releasing nanomedicines. In conclusion, this work details a strategy for determining the effect of formulation variability on in vivo performance, thereby informing the translation of PNPs, and other NPs, from the laboratory to the clinic.

Comparative Antibacterial and Efflux Pump Inhibitory Activity of Isolated Nerolidol, Farnesol, and α-Bisabolol Sesquiterpenes and Their Liposomal Nanoformulations

The efflux systems are considered important mechanisms of bacterial resistance due to their ability to extrude various antibiotics. Several naturally occurring compounds, such as sesquiterpenes, have demonstrated antibacterial activity and the ability to inhibit efflux pumps in resistant strains. Therefore, the objective of this research was to analyze the antibacterial and inhibitory activity of the efflux systems NorA, Tet(K), MsrA, and MepA by sesquiterpenes nerolidol, farnesol, and α-bisabolol, used either individually or in liposomal nanoformulation, against multi-resistant Staphylococcus aureus strains. The methodology consisted of in vitro testing of the ability of sesquiterpenes to reduce the Minimum Inhibitory Concentration (MIC) and enhance the action of antibiotics and ethidium bromide (EtBr) in broth microdilution assays. The following strains were used: S. aureus 1199B carrying the NorA efflux pump, resistant to norfloxacin; IS-58 strain carrying Tet(K), resistant to tetracyclines; RN4220 carrying MsrA, conferring resistance to erythromycin. For the EtBr fluorescence measurement test, K2068 carrying MepA was used. It was observed the individual sesquiterpenes exhibited better antibacterial activity as well as efflux pump inhibition. Farnesol showed the lowest MIC of 16.5 µg/mL against the S. aureus RN4220 strain. Isolated nerolidol stood out for reducing the MIC of EtBr to 5 µg/mL in the 1199B strain, yielding better results than the positive control CCCP, indicating strong evidence of NorA inhibition. The liposome formulations did not show promising results, except for liposome/farnesol, which reduced the MIC of EtBr against 1199B and RN4220. Further research is needed to evaluate the mechanisms of action involved in the inhibition of resistance mechanisms by the tested compounds.

Cationic Dextran Stearate (Dex-St-GTMAC): Synthesis and Evaluation as Polymeric Micelles for Indomethacin Corneal Penetration

Background Indomethacin as a non-steroidal anti-inflammatory drug (NSAID) is commonly used to treat some ocular inflammatory disorders. Unfortunately, indomethacin is a drug that is poorly soluble in water; therefore, it has low efficacy. An attractive approach is the targeted delivery of indomethacin to the cornea using cationic dextran stearate as a polymeric micelle drug carrier. Methods A dextran stearate-glycidyl trimethylammonium chloride (Dex-St-GTMAC) copolymer was prepared through the reaction of GTMAC, stearoyl chloride, and dextran. Then, Dex-St-GTMAC was characterized by Fourier transform infrared (FT-IR) spectroscopy and 1H NMR spectroscopy. Dex-St-GTMAC forms micelles in the presence of indomethacin. The prepared polymeric micelles were characterized for size, ζ-potential, drug loading, particle morphology, critical micelle concentration, and encapsulation efficiency. To study the irritation potential of the indomethacin-loaded Dex-St-GTMAC, Het-Cam and Draize tests have been performed. Prepared cationic micelles were subjected to the in vitro drug release and ex vivotrans-corneal permeation test. Results The dialysis method was used for the preparation of indomethacin-loaded micelles (10, 20, and 30%). Measurement of the particle size showed a mean diameter of 122.1 and 150.9 nm for the drug-loaded micelles. Scanning electron microscopy (SEM) images showed that the morphology of the particles is spherical. 10% formulation was chosen as the best formulation due to more surface charge and reasonable drug loading. ζ-potential measurement for the 10% drug-containing micelles showed a value of +39.1 mV. Drug loading efficiency and the encapsulation efficiency for 10% drug-containing micelles were 6.36 and 63.61%, respectively. The results of the Het-Cam and Draize tests indicated that the indomethacin-loaded Dex-St-GTMAC formulation had no toxicity to eye tissues. Based on our results, the prepared micelles (indomethacin-loaded Dex-St-GTMAC) exhibited a sustained drug release pattern compared to the control group. Indomethacin penetration from the micelles to the excised bovine cornea was 1.75-fold greater than the control (indomethacin 0.1% in phosphate-buffered saline (PBS)). Conclusions Data from the ζ-potential, SEM, drug loading capacity, and in vitro drug release studies indicated that cationic dextran stearate polymeric micelles are an appropriate carrier for the efficient penetration of indomethacin into cornea tissues.

Valencene, Nootkatone and Their Liposomal Nanoformulations as Potential Inhibitors of NorA, Tet(K), MsrA, and MepA Efflux Pumps in Staphylococcus aureus Strains

Valencene and nootkatone are aromatic sesquiterpenes with known biological activities, such as antimicrobial, antioxidant, anti-inflammatory, and antitumor. Given the evidence that encapsulation into nanosystems, such as liposomes, could improve the properties of several compounds, the present study aimed to evaluate the activity of these sesquiterpenes in their isolated state or in liposomal formulations against strains of Staphylococcus aureus carrying efflux pumps. The broth microdilution method evaluated the antibiotic-enhancing activity associated with antibiotics and ethidium bromide (EtBr). The minimum inhibitory concentration was assessed in strains of S. aureus 1199B, IS-58, and RN4220, which carry the efflux proteins NorA, Tet(K), and MsrA. In tests with strain 1199B, valencene reduced the MIC of norfloxacin and EtBr by 50%, while the liposomal formulation of this compound did not show a significant effect. Regarding the strain IS-58, valencene, and its nanoformulation reduced norfloxacin MIC by 60.3% and 50%, respectively. In the non-liposomal form, the sesquiterpene reduced the MIC of EtBr by 90%. Against the RN4220 strain, valencene reduced the MIC of the antibiotic and EtBr by 99% and 93.7%, respectively. Nootkatone and its nanoformulation showed significant activity against the 1199B strain, reducing the EtBr MIC by 21.9%. Against the IS-58 strain, isolated nootkatone reduced the EtBr MIC by 20%. The results indicate that valencene and nootkatone potentiate the action of antibiotics and efflux inhibitors in strains carrying NorA, Tet(K), and MsrA proteins, which suggests that these sesquiterpenes act as efflux pump inhibitors in S. aureus. Therefore, further studies are needed to assess the impact of incorporation into liposomes on the activity of these compounds in vivo.

Redox-Sensitive Delivery of Doxorubicin from Nanoparticles of Poly(ethylene glycol)-Chitosan Copolymer for Treatment of Drug-Resistant Oral Cancer Cells

Reactive oxygen species (ROS)-sensitive polymer nanoparticles were synthesized for tumor targeting of an anticancer drug, doxorubicin (DOX). For this purpose, chitosan-methoxy poly(ethylene glycol) (mPEG) (ChitoPEG)-graft copolymer was synthesized and then DOX was conjugated to the backbone of chitosan using a thioketal linker. Subsequently, the chemical structure of the DOX-conjugated ChitoPEG copolymer (ChitoPEGthDOX) was confirmed via 1H nuclear magnetic resonance (NMR) spectra. Nanoparticles of the ChitoPEGthDOX conjugates have spherical shapes and a size of approximately 100 nm. Transmission electron microscopy (TEM) has shown that ChitoPEGthDOX nanoparticles disintegrate in the presence of hydrogen peroxide and the particle size distribution also changes from a monomodal/narrow distribution pattern to a multi-modal/wide distribution pattern. Furthermore, DOX is released faster in the presence of hydrogen peroxide. These results indicated that ChitoPEGthDOX nanoparticles have ROS sensitivity. The anticancer activity of the nanoparticles was evaluated using AT84 oral squamous carcinoma cells. Moreover, DOX-resistant AT84 cells were prepared in vitro. DOX and its nanoparticles showed dose-dependent cytotoxicity in both DOX-sensitive and DOX-resistant AT84 cells in vitro. However, DOX itself showed reduced cytotoxicity against DOX-resistant AT84 cells, while the nanoparticles showed almost similar cytotoxicity to DOX-sensitive and DOX-resistant AT84 cells. This result may be due to the inhibition of intracellular delivery of free DOX, while nanoparticles were efficiently internalized in DOX-resistant cells. The in vivo study of a DOX-resistant AT84 cell-bearing tumor xenograft model showed that nanoparticles have higher antitumor efficacy than those found in free DOX treatment. These results may be related to the efficient accumulation of nanoparticles in the tumor tissue, i.e., the fluorescence intensity in the tumor tissue was stronger than that of any other organs. Our findings suggest that ChitoPEGthDOX nanoparticles may be a promising candidate for ROS-sensitive anticancer delivery against DOX-resistant oral cancer cells.

Size effect of fluorescent thiol-organosilica particles on their distribution in the mouse spleen

We investigated the distribution of intravenously administered thiol-organosilica particle (thiol-OS) in the spleen to evaluate their size effect in mice. A single administration of particles of thiol-OS containing rhodamine B (Rh) (90, 280, 340, 450, 630, 1110, 1670, and 3030 nm in diameter) was performed. After 24 h, we conducted a combination analysis using histological studies by fluorescent microscopy and quantitative inductively coupled plasma optical emission spectrometry (ICP-OES), which revealed no clear correlation between the particle size and spleen uptake of particle weight and number per tissue weight, and the injection dose. Moreover, Rh with 450 nm diameter (Rh450) showed the highest uptake, and Rh with 340 nm diameter (Rh340) showed the lowest uptake. Histologically, large fluorescent areas in the marginal zone (MZ) and red pulp (RP) of the spleen were observed for all particle sizes, but less in the follicle of white pulp. Using combination analysis using the particle weights of ICP-OES and the fluorescent area, we compared the distributions of each particle in each region. Rh450 had the largest accumulated weight in the MZ and RP. Particles larger than Rh450 showed negative correlations between their sizes and accumulated weight in the MZ and RP. Simultaneous dual administration of particles using Rhs and thiol-OS containing fluorescein (90 nm in diameter) showed the size-dependent difference in cellular distribution and intracellular localization. Immunohistochemical staining against macrophage markers, CD169, and F4/80 showed various colocalization patterns with macrophages that uptook particles, indicating differences in particle uptake in each macrophage may have novel significance.

Targeted nanotherapy for kidney diseases: a comprehensive review

Kidney diseases represent a major public health problem, affecting millions of people worldwide. Moreover, the treatment of kidney diseases is burdened by the problematic effects of conventional drug delivery, such as systemic drug toxicity, rapid drug clearance, and the absence of precise targeting of the kidney. Although the use of nanotechnology in medicine is in its early stage and lacks robust translational studies, nanomedicines have already shown great promise as novel drug-delivery systems for the treatment of kidney disease. On the basis of our current knowledge of renal anatomy and physiology, pathophysiology of kidney diseases, and physicochemical characteristics of nanoparticles, an expansive repertoire and wide use of nanomedicines could be developed for kidney diseases in the near future. Some limitations have slowed the transition of these agents from preclinical studies to clinical trials, however. In this review, we summarize the current knowledge on renal drug-delivery systems and recent advances in renal cell targeting; we also demonstrate their important potential as future paradigm-shifting therapies for kidney diseases.

Dissolved metal ion removal by online hollow fiber ultrafiltration for enhanced size characterization of metal-containing nanoparticles with single-particle ICP-MS

Single particle-inductively coupled plasma mass spectrometry (SP-ICP-MS) is a powerful tool for size-characterization of metal-containing nanoparticles (MCNs) at environmentally relevant concentrations, however, coexisting dissolved metal ions greatly interfere with the accuracy of particle size analysis. The purpose of this study is to develop an online technique that couples hollow fiber ultrafiltration (HFUF) with SP-ICP-MS to improve the accuracy and size detection limit of MCNs by removing metal ions from suspensions of MCNs. Through systematic optimization of conditions including the type and concentration of surfactant and complexing agent, carrier pH, and ion cleaning time, HFUF completely removes metal ions but retains the MCNs in suspension. The optimal conditions include using a mixture of 0.05 vol.% FL-70 and 0.5 mmol/L Na₂S₂O₃ (pH = 8.0) as the carrier and 4 min as the ion cleaning time. At these conditions, HFUF-SP-ICP-MS accurately determines the sizes of MCNs, and the results agree with the size distribution determined by transmission electron microscopy, even when metal ions also are present in the sample. In addition, reducing the ionic background through HFUF also lowers the particle size detection limit with SP-ICP-MS (e.g., from 28.3 to 14.2 nm for gold nanoparticles). This size-based ion-removal principle provided by HFUF is suitable for both cations (e.g., Ag⁺) and anions (e.g., AuCl₄^-) and thus has good versatility compared to ion exchange purification and promising prospects for the removal of salts and macromolecules before single particle analysis.

Manipulation of Redox Metabolism Using Pharmacologic Ascorbate Opens a Therapeutic Window for Radio-Sensitization by ATM Inhibitors in Colorectal Cancer

PURPOSE

Ataxia telangiectasia mutated kinase (ATM) inhibitors are potent radiosensitizers that regulate DNA damage responses and redox metabolism, but they have not been translated clinically because of the potential for excess normal tissue toxicity. Pharmacologic ascorbate (P-AscH-; intravenous administration achieving mM plasma concentrations) selectively enhances H2O2-induced oxidative stress and radiosensitization in tumors while acting as an antioxidant and mitigating radiation damage in normal tissues including the bowel. We hypothesized that P-AscH- could enhance the therapeutic index of ATM inhibitor-based chemoradiation by simultaneously enhancing the intended effects of ATM inhibitors in tumors and mitigating off-target effects in adjacent normal tissues.

METHODS AND MATERIALS

Clonogenic survival was assessed in human (human colon tumor [HCT]116, SW480, HT29) and murine (CT26, MC38) colorectal tumor lines and normal cells (human umbilical vein endothelial cell, FHs74) after radiation ± DNA repair inhibitors ± P-AscH-. Tumor growth delay was assessed in mice with HCT116 or MC38 tumors after fractionated radiation (5 Gy × 3) ± the ATM inhibitor KU60019 ± P-AscH-. Intestinal injury, oxidative damage, and transforming growth factor β immunoreactivity were quantified using immunohistochemistry after whole abdominal radiation (10 Gy) ± KU60019 ± P-AscH-. Cell cycle distribution and ATM subcellular localization were assessed using flow cytometry and immunohistochemistry. The role of intracellular H2O2 fluxes was assessed using a stably expressed doxycycline-inducible catalase transgene.

RESULTS

KU60019 with P-AscH- enhanced radiosensitization in colorectal cancer models in vitro and in vivo by H2O2-dependent oxidative damage to proteins and enhanced DNA damage, abrogation of the postradiation G2 cell cycle checkpoint, and inhibition of ATM nuclear localization. In contrast, concurrent P-AscH- markedly reduced intestinal toxicity and oxidative damage with KU60019.

CONCLUSIONS

We provide evidence that redox modulating drugs, such as P-AscH-, may facilitate the clinical translation of ATM inhibitors by enhancing tumor radiosensitization while simultaneously protecting normal tissues.

Recent advances in flavonoid-based nanocarriers as an emerging drug delivery approach for cancer chemotherapy

Flavonoids are an interesting class of biomolecules, which exhibit cancer-inhibitory effects through both chemopreventive and chemotherapeutic activities. However, their therapeutic efficacy is affected by poor pharmacokinetics (PK) and biopharmaceutical attributes. One of the most promising approaches to resolve these issues is to formulate flavonoids in nanosystems. Different flavonoid nanoformulations have shown therapeutic superiority over free flavonoids. Functionalization of nanoparticles (NPs) further improves their therapeutic efficacy by facilitating site-specific delivery and reducing nonspecific toxicities. In this review, we highlight recent developments in the field of flavonoid-based NPs to gain translational insights into the potential applications of flavonoid-based nanocarriers in cancer management.

Insights on Development Aspects of Polymeric Nanocarriers: The Translation from Bench to Clinic

Scientists are focusing immense attention on polymeric nanocarriers as a prominent delivery vehicle for several biomedical applications including diagnosis of diseases, delivery of therapeutic agents, peptides, proteins, genes, siRNA, and vaccines due to their exciting physicochemical characteristics which circumvent degradation of unstable drugs, reduce toxic side effects through controlled release, and improve bioavailability. Polymers-based nanocarriers offer numerous benefits for in vivo drug delivery such as biocompatibility, biodegradability, non-immunogenicity, active drug targeting via surface modification, and controlled release due to their pH—and thermosensitive characteristics. Despite their potential for medicinal use, regulatory approval has been achieved for just a few. In this review, we discuss the historical development of polymers starting from their initial design to their evolution as nanocarriers for therapeutic delivery of drugs, peptides, and genes. The review article also expresses the applications of polymeric nanocarriers in the pharmaceutical and medical industry with a special emphasis on oral, ocular, parenteral, and topical application of drugs, peptides, and genes over the last two decades. The review further examines the practical, regulatory, and clinical considerations of the polymeric nanocarriers, their safety issues, and directinos for future research.

PDA-Based Drug Delivery Nanosystems: A Potential Approach for Glioma Treatment

Glioma is characterized by high mortality and low postoperative survival. Despite the availability of various therapeutic approaches and molecular typing, the treatment failure rate and the recurrence rate of glioma remain high. Given the limitations of existing therapeutic tools, nanotechnology has emerged as an alternative treatment option. Nanoparticles, such as polydopamine (PDA)-based nanoparticles, are embodied with reliable biodegradability, efficient drug loading rate, relatively low toxicity, considerable biocompatibility, excellent adhesion properties, precisely targeted delivery, and strong photothermal conversion properties. Therefore, they can further enhance the therapeutic effects in patients with glioma. Moreover, polydopamine contains pyrocatechol, amino and carboxyl groups, active double bonds, catechol, and other reactive groups that can react with biofunctional molecules containing amino, aldehyde, or sulfhydryl groups (main including, self-polymerization, non-covalent self-assembly, π-π stacking, electrostatic attraction interaction, chelation, coating and covalent co-assembly), which form a reversible dynamic covalent Schiff base bond that is extremely sensitive to pH values. Meanwhile, PDA has excellent adhesion capability that can be further functionally modified. Consequently, the aim of this review is to summarize the application of PDA-based NPs in glioma and to acquire insight into the therapeutic effect of the drug-loaded PDA-based nanocarriers (PDA NPs). A wealthy understanding and argument of these sides is anticipated to afford a better approach to develop more reasonable and valid PDA-based cancer nano-drug delivery systems. Finally, we discuss the expectation for the prospective application of PDA in this sphere and some individual viewpoints.

Mineralized vectors for gene therapy

There is an intense interest in developing materials for safe and effective delivery of polynucleotides using non-viral vectors. Mineralization of organic templates has long been used to produce complex materials with outstanding biocompatibility. However, a lack of control over mineral growth has limited the applicability of mineralized materials to a few in vitro applications. With better control over mineral growth and surface functionalization, mineralized vectors have advanced significantly in recent years. Here, we review the recent progress in chemical synthesis, physicochemical properties, and applications of mineralized materials in gene therapy, focusing on structure-function relationships. We contrast the classical understanding of the mineralization mechanism with recent ideas of mineralization. A brief introduction to gene delivery is summarized, followed by a detailed survey of current mineralized vectors. The vectors derived from calcium phosphate are articulated and compared to other minerals with unique features. Advanced mineral vectors derived from templated mineralization and specialty coatings are critically analyzed. Mineral systems beyond the co-precipitation are explored as more complex multicomponent systems. Finally, we conclude with a perspective on the future of mineralized vectors by carefully demarcating the boundaries of our knowledge and highlighting ambiguous areas in mineralized vectors. STATEMENT OF SIGNIFICANCE: Therapy by gene-based medicines is increasingly utilized to cure diseases that are not alleviated by conventional drug therapy. Gene medicines, however, rely on macromolecular nucleic acids that are too large and too hydrophilic for cellular uptake. Without tailored materials, they are not functional for therapy. One emerging class of nucleic acid delivery system is mineral-based materials. The fact that they can undergo controlled dissolution with minimal footprint in biological systems are making them attractive for clinical use, where safety is utmost importance. In this submission, we will review the emerging synthesis technology and the range of new generation minerals for use in gene medicines.

Processing Parameters and Ion Excipients Affect the Physicochemical Characteristics of the Stereocomplex-Formed Polylactide-b-Polyethylene Glycol Nanoparticles and Their Pharmacokinetics

To optimize the characteristics of stereocomplex polylactide-b-polyethylene glycol nanoparticles (SC-PEG NPs) in terms of pharmacokinetics (PK), we chose continuous anti-solvent precipitation with a T-junction as a preparation method and investigated the effect of using solvents containing an ion excipient (lithium bromide, LiBr) on the characteristics of SC-PEG NPs by changing the processing temperature and total flow rate (TFR). Processing temperatures above the melting temperature (T_m) of the PEG domain produced a sharper polydispersity and denser surface PEG densities of SC-PEG NPs than those produced by processing temperatures below the Tm of the PEG domains. Response surface analysis revealed that a higher LiBr concentration and slower TFR resulted in larger and denser hydrodynamic diameters (D_h) and surface PEG densities, respectively. However, a high concentration (300 mM) of LiBr resulted in a decreased drug loading content (DLC). ¹⁴C-tamoxifen-loaded ¹¹¹In-SC-PEG NPs with larger D_h and denser surface PEG densities showed a prolonged plasma retention and low tissue distribution after intravenous injection in mice. These results indicate that the novel strategy of using solvents containing LiBr at different processing temperatures and TFR can broadly control characteristics of SC-PEG NPs, such as D_h, surface PEG densities, and DLC, which alter the PK profiles and tissue distributions.

Synthesis of Polyethylene Glycol Diacrylate/Acrylic Acid Nanoparticles as Nanocarriers for the Controlled Delivery of Doxorubicin to Colorectal Cancer Cells

Doxorubicin (Dox) is known for its potential to deliver desirable anticancer effects against various types of cancer including colorectal cancer. However, the adverse effects are serious. This study aimed to synthesize polyethylene glycol diacrylate (PEGDA)/acrylic acid (AA)-based nanoparticles (PEGDA/AA NPs) for Dox delivery to colorectal cancer cells. The NPs were synthesized using free-radical polymerization reaction using the monomers PEGDA and AA with their physical properties, drug loading and release, biocompatibility, and anticancer effect evaluated. The NPs were spherical with a size of around 230 nm, with a 48% Dox loading efficiency and with loading capacity of 150 µg/mg. Intriguingly, the NPs had the ability to prolong the release of Dox in vitro over 24 h and were non-toxic to intestinal epithelial cells. Dox-loaded PEGDA/AA NPs (Dox-NPs) were able to effectively kill the colorectal cancer cell line (HT-29) with the Dox-NPs accumulating inside the cell and killing the cell through the apoptosis pathway. Overall, the synthesized PEGDA/AA NPs exhibit considerable potential as a drug delivery carrier for colon cancer-directed, staged-release therapy.

The Hitchhiker's Guide to Human Therapeutic Nanoparticle Development

Nanomedicine plays an essential role in developing new therapies through novel drug delivery systems, diagnostic and imaging systems, vaccine development, antibacterial tools, and high-throughput screening. One of the most promising drug delivery systems are nanoparticles, which can be designed with various compositions, sizes, shapes, and surface modifications. These nanosystems have improved therapeutic profiles, increased bioavailability, and reduced the toxicity of the product they carry. However, the clinical translation of nanomedicines requires a thorough understanding of their properties to avoid problems with the most questioned aspect of nanosystems: safety. The particular physicochemical properties of nano-drugs lead to the need for additional safety, quality, and efficacy testing. Consequently, challenges arise during the physicochemical characterization, the production process, in vitro characterization, in vivo characterization, and the clinical stages of development of these biopharmaceuticals. The lack of a specific regulatory framework for nanoformulations has caused significant gaps in the requirements needed to be successful during their approval, especially with tests that demonstrate their safety and efficacy. Researchers face many difficulties in establishing evidence to extrapolate results from one level of development to another, for example, from an in vitro demonstration phase to an in vivo demonstration phase. Additional guidance is required to cover the particularities of this type of product, as some challenges in the regulatory framework do not allow for an accurate assessment of NPs with sufficient evidence of clinical success. This work aims to identify current regulatory issues during the implementation of nanoparticle assays and describe the major challenges that researchers have faced when exposing a new formulation. We further reflect on the current regulatory standards required for the approval of these biopharmaceuticals and the requirements demanded by the regulatory agencies. Our work will provide helpful information to improve the success of nanomedicines by compiling the challenges described in the literature that support the development of this novel encapsulation system. We propose a step-by-step approach through the different stages of the development of nanoformulations, from their design to the clinical stage, exemplifying the different challenges and the measures taken by the regulatory agencies to respond to these challenges.

Thioanisole ester based logic gate cascade to control ROS-triggered micellar degradation

Thioanisole ester polymer side chains hydrolyze exclusively upon thioether oxidation, showing logic gate response. ROS-induced ester hydrolysis on the hydrophobic domain leads to nanocarrier disassembly with potential for targeted drug release.

Safety Evaluation of Nanotechnology Products

Nanomaterials are now being used in a wide variety of biomedical applications. Medical and health-related issues, however, have raised major concerns, in view of the potential risks of these materials against tissue, cells, and/or organs and these are still poorly understood. These particles are able to interact with the body in countless ways, and they can cause unexpected and hazardous toxicities, especially at cellular levels. Therefore, undertaking in vitro and in vivo experiments is vital to establish their toxicity with natural tissues. In this review, we discuss the underlying mechanisms of nanotoxicity and provide an overview on in vitro characterizations and cytotoxicity assays, as well as in vivo studies that emphasize blood circulation and the in vivo fate of nanomaterials. Our focus is on understanding the role that the physicochemical properties of nanomaterials play in determining their toxicity.

Physico-chemical characterization of kajjali, black sulphide of mercury, with respect to the role of sulfur in its formation and structure

BACKGROUND

Kajjali is used as a base for Ayurvedic herbo-mineral medicines. It is a combination of mercury with sulfur in varying proportions. The ratio of sulfur (S) added to mercury (Hg) directly relates to the therapeutic efficacy of the compound.

OBJECTIVE

To analyze the physico-chemical characteristics of samaguna gandhaka kajjali (Hg: S = 1:1) and shadaguna gandhaka kajjali (Hg: S = 1:6).

MATERIALS AND METHODS

X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy (XPS), Fourier transmission infrared spectroscopy, thermo-gravimetry analysis, and atomic absorption spectroscopy were applied to characterize each type of kajjali.

RESULTS

It was found that the particle size of the formed kajjali compound increases with a decrease in the mercury to sulfur ratio. The presence of excess sulfur does not change the surface oxidation states as revealed by the XPS analysis. No trace of mercury has been found in both samaguna gandhaka kajjali (SGK-1) and shadguna gandhaka kajjali (SGK-6), indicating a complete Hg reaction with S.

CONCLUSION

Kajjali simulates nanomaterial of the modern era and possesses therapeutic efficacy as mentioned in classical Ayurveda texts. Complete trituration of mercury and sulfur combination ends up with this kajjali formation incorporating the potency of nanotherapeutics.

Targeted Delivery of Drugs and Genes Using Polymer Nanocarriers for Cancer Therapy

Cancer is one of the primary causes of worldwide human deaths. Most cancer patients receive chemotherapy and radiotherapy, but these treatments are usually only partially efficacious and lead to a variety of serious side effects. Therefore, it is necessary to develop new therapeutic strategies. The emergence of nanotechnology has had a profound impact on general clinical treatment. The application of nanotechnology has facilitated the development of nano-drug delivery systems (NDDSs) that are highly tumor selective and allow for the slow release of active anticancer drugs. In recent years, vehicles such as liposomes, dendrimers and polymer nanomaterials have been considered promising carriers for tumor-specific drug delivery, reducing toxicity and improving biocompatibility. Among them, polymer nanoparticles (NPs) are one of the most innovative methods of non-invasive drug delivery. Here, we review the application of polymer NPs in drug delivery, gene therapy, and early diagnostics for cancer therapy.

Mechanistic Investigations into and Control of Anisotropic Metal-Organic Framework Growth

The porphyrinic metal-organic framework, PCN-222, exhibits anisotropic growth behavior to form nanorods and microrods with aspect ratios 3 < x < 94. Control of microrod aspect ratios has been demonstrated through the identification of several factors that dictate crystal growth, particularly the concentrations of a ligand, a modulator, and an exogenous base. An increase in the local concentration of a deprotonated ligand, which is proportional to the nucleation rate, is associated with smaller crystals, while increased modulator concentration leads to longer microrods. Addition of a deprotonating agent not only contributes to higher aspect ratios but also results in an improvement to particle dispersity. Here, we report acid-base co-modulation methods with difluoroacetic acid and triethylamine to effectively tune PCN-222 aspect ratios. A series of mechanisms is identified for the growth of PCN-222: (1) ligand deprotonation, (2) nucleation, (3) oriented attachment, (4) Ostwald ripening, and (5) dissolution-recrystallization. Time trials of co-modulated samples revealed three separate ripening growth events, with each resulting in larger and more monodisperse crystals. With an understanding of these crystal growth factors and mechanisms, the highest aspect ratio, non-templated metal-organic frameworks were synthesized (94 ± 9).

Nanomaterials for the Diagnosis and Treatment of Head and Neck Cancers: A Review

Head and neck cancer (HNC) is a category of cancers that typically arise from the nose-, mouth-, and throat-lining squamous cells. The later stage of HNC diagnosis significantly affects the patient's survival rate. This makes it mandatory to diagnose this cancer with a suitable biomarker and imaging techniques at the earlier stages of growth. There are limitations to traditional technologies for early detection of HNC. Furthermore, the use of nanocarriers for delivering chemo-, radio-, and phototherapeutic drugs represents a promising approach for improving the outcome of HNC treatments. Several studies with nanostructures focus on the development of a targeted and sustained release of anticancer molecules with reduced side effects. Besides, nanovehicles could allow co-delivering of anticancer drugs for synergistic activity to counteract chemo- or radioresistance. Additionally, a new generation of smart nanomaterials with stimuli-responsive properties have been developed to distinguish between unique tumor conditions and healthy tissue. In this light, the present article reviews the mechanisms used by different nanostructures (metallic and metal oxide nanoparticles, polymeric nanoparticles, quantum dots, liposomes, nanomicelles, etc.) to improve cancer diagnosis and treatment, provides an up-to-date picture of the state of the art in this field, and highlights the major challenges for future improvements.

Biomimetic PLGA Microbubbles Coated with Platelet Membranes for Early Detection of Myocardial Ischaemia-Reperfusion Injury

Early diagnosis of myocardial ischaemia-reperfusion (MI/R) injury is important for protecting the myocardium and improving patient prognoses. Fortunately, the platelet membrane possesses the ability to target the region of MI/R injury. Therefore, we hypothesized that platelet membrane-coated particles (PMPs) could be used to detect early MI/R injury by ultrasound imaging. We designed PMPs with a porous polylactic-co-glycolic acid (PLGA) core coated with a platelet membrane shell. Red blood cell membrane-coated particles (RMPs) were fabricated as controls. Transmission electron microscopy (TEM) and fluorescence microscopy were applied to confirm the membrane coatings of the PMPs and RMPs. In vitro imaging of the PMPs and RMPs was verified. Moreover, binding experiments were designed to examine the targeting ability of the PMPs. Finally, we assessed the signal intensity of the adherent PMPs in the risk area and remote area by ultrasound imaging based on an MI/R rat model. The platelet membrane equipped the PMPs with an accurate targeting ability. Compared with RMPs, PMPs showed significantly more adhesion to human umbilical vein endothelial cells and collagen IV in vitro. Both PMPs and RMPs exhibited good enhancement ability in vitro and in vivo. Furthermore, the signal intensity of PMPs in the risk area was significantly higher than that in remote areas. These results were further validated by an immunofluorescence assay and ex vivo fluorescence imaging. In summary, ultrasound imaging with PMPs can detect early MI/R injury in a noninvasive manner.

Size, shape, charge and "stealthy" surface: Carrier properties affect the drug circulation time in vivo

The present review sets out to discuss recent developments of the effects and mechanisms of carrier properties on their circulation time. For most drugs, sufficient in vivo circulation time is the basis of high bioavailability. Drug carrier plays an irreplaceable role in helping drug avoid being quickly recognized and cleared by mononuclear phagocyte system, to give drug enough time to arrive at targeted organ and tissue to play its therapeutic effect. The physical and chemical properties of drug carriers, such as size, shape, surface charge and surface modification, would affect their in vivo circulation time, metabolic behavior and biodistribution. The final circulation time of carriers is determined by the balance between macrophage recognitions, blood vessel penetration and urine excretion. Therefore, when designing the drug delivery system, we should pay much attention to the properties of drug carriers to get enough in vivo circulation time to arrive at target site eventually. This article mainly reviews the effect of carrier size, size, surface charge and surface properties on its circulation time in vivo, and discusses the mechanism of these properties affecting circulation time. This review has reference significance for the research of long-circulation drug delivery system.

Treating colon cancers with a non-conventional yet strategic approach: An overview of various nanoparticulate systems

Regardless of progress in therapy management which are developed for colon cancer (CC), it remains the third most common cause of mortality due to cancers around the world. Conventional medicines pose side effects due to untoward action on non-target cells. Their inability to deliver drugs to the affected regions of the colon locally, in a reproducible manner raises a concern towards the efficacy of therapy. In this regard, nanoparticles emerged as a promising drug delivery system due to their flexibility in designing, drug release modulation and cancer cell targeting. Not only are nanoparticles making their way into colon cancer research in the revolution of conventional onco-therapeutics, but they also offer promising scope in the development of colon cancer vaccines and theranostic tools. However, there are challenges with respect to drug delivery using nanoparticles, which may hamper the delivery of these novel carriers to the colon. The present review addresses recent advents in nanotechnology for colon-specific drug delivery (CDDS) which may help to overcome the existing challenges and intends to recognize futuristic potentials in the treatment of CC with CDDS.

Short interfering RNA delivered by a hybrid nanoparticle targeting VEGF: Biodistribution and anti-tumor effect

BACKGROUND

The use of RNA interference (iRNA) therapy has proved to be an interesting target therapy for the cancer treatment; however, siRNAs are unstable and quickly eliminated from the bloodstream. To face these barriers, the use of biocompatible and efficient nanocarriers emerges as an alternative to improve the success application of iRNA to the cancer, including breast cancer.

RESULTS

A hybrid nanocarrier composed of calcium phosphate as the inorganic phase and a block copolymer containing polyanions as organic phase, named HNPs, was developed to deliver VEGF siRNA into metastatic breast cancer in mice. The particles presented a rounded shape by TEM images with average size measured by DLS suitable and biocompatible for biomedical applications. The XPS and EDS spectra confirmed the hybrid composition of the nanoparticles. Moreover, after intravenous administration, the particles accumulated mainly in the tumor site and kidneys, which demonstrates the tumor targeting accumulation through the Enhanced Permeability and Retention Effect (EPR). A significant decrease in size of the tumors treated with the nanoparticles containing siVEGF (HNPs-siVEGF) was observed and the reduction was related to enhanced tumor accumulation of siRNA as well as in vivo VEGF silencing at gene and protein levels.

CONCLUSION

The hybrid system prepared was successful in promoting the RNAi effect in vivo with very low toxicity.

GENERAL SIGNIFICANCE

This study shows the valuable development of a hybrid nanoparticle carrying VEGF siRNA, as well as their tumor targeting, accumulation and reduction in mice triple-negative breast cancer.

Co-delivery of etoposide and cisplatin in dual-drug loaded nanoparticles synergistically improves chemoradiotherapy in non-small cell lung cancer models

Chemoradiotherapy with cisplatin and etoposide is a curative management regimen for both small and non-small cell lung cancers. While the treatment regimen is effective, it also has a high toxicity profile. One potential strategy to improve the therapeutic ratio of chemoradiation is to utilize nanotherapeutics. Nanoparticle formulation of cisplatin and etoposide, however, is challenging due to the significant mismatch in chemical properties of cisplatin and etoposide. Herein we report the formulation of a polymeric nanoparticle formulation of cisplatin and etoposide using a prodrug approach. We synthesized a hydrophobic platinum prodrug, which was then co-delivered with etoposide using a nanoparticle. Using mouse models of lung cancer, we demonstrated that dual-drug loaded nanoparticles are significantly more effective than small molecule chemotherapy in chemoradiotherapy. These results support further investigation of nanoparticle-based drug formulations of combination chemotherapies and the use of nanotherapeutics in chemoradiotherapy. STATEMENT OF SIGNIFICANCE: The treatment of lung cancer often involves a combination of chemotherapy and radiation. While it can be effective, it also has a high toxicity profile. Preferential delivery of chemotherapeutics to the tumor while avoiding normal tissue would improve efficacy and lower toxicity. While this is challenging with conventional drug delivery technologies, nanotechnology offers a unique opportunity. In this study, we have engineered nanoparticles that are loaded with combination chemotherapeutics and showed such nanotherapeutics are more effective and less toxic than free chemotherapeutics in chemoradiotherapy. Our work highlights the importance and potential of nanoformulations of combination chemotherapy in chemoradiotherapy and cancer treatment. This approach can be translated clinically and it can have a significant impact on cancer treatment.

APTES monolayer coverage on self-assembled magnetic nanospheres for controlled release of anticancer drug Nintedanib

The use of an appropriate delivery system capable of protecting, translocating, and selectively releasing therapeutic moieties to desired sites can promote the efficacy of an active compound. In this work, we have developed a nanoformulation which preserves its magnetization to load a model anticancerous drug and to explore the controlled release of the drug in a cancerous environment. For the preparation of the nanoformulation, self-assembled magnetic nanospheres (MNS) made of superparamagnetic iron oxide nanoparticles were grafted with a monolayer of (3-aminopropyl)triethoxysilane (APTES). A direct functionalization strategy was used to avoid the loss of the MNS magnetization. The successful preparation of the nanoformulation was validated by structural, microstructural, and magnetic investigations. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) were used to establish the presence of APTES on the MNS surface. The amine content quantified by a ninhydrin assay revealed the monolayer coverage of APTES over MNS. The monolayer coverage of APTES reduced only negligibly the saturation magnetization from 77 emu/g (for MNS) to 74 emu/g (for MNS-APTES). Detailed investigations of the thermoremanent magnetization were carried out to assess the superparamagnetism in the MNS. To make the nanoformulation pH-responsive, the anticancerous drug Nintedanib (NTD) was conjugated with MNS-APTES through the acid liable imine bond. At pH 5.5, which mimics a cancerous environment, a controlled release of 85% in 48 h was observed. On the other hand, prolonged release of NTD was found at physiological conditions (i.e., pH 7.4). In vitro cytotoxicity study showed dose-dependent activity of MNS-APTES-NTD for human lung cancer cells L-132. About 75% reduction in cellular viability for a 100 μg/mL concentration of nanoformulation was observed. The nanoformulation designed using MNS and monolayer coverage of APTES has potential in cancer therapy as well as in other nanobiological applications.

Marine Exopolysaccharide Complexed With Scandium Aimed as Theranostic Agents

(1) Background: Exopolysaccharide (EPS) derivatives, produced by Alteromonas infernus bacterium, showed anti-metastatic properties. They may represent a new class of ligands to be combined with theranostic radionuclides, such as ⁴⁷Sc/⁴⁴Sc. The goal of this work was to investigate the feasibility of such coupling. (2) Methods: EPSs, as well as heparin used as a drug reference, were characterized in terms of molar mass and dispersity using Asymmetrical Flow Field-Flow Fractionation coupled to Multi-Angle Light Scattering (AF4-MALS). The intrinsic viscosity of EPSs at different ionic strengths were measured in order to establish the conformation. To determine the stability constants of Sc with EPS and heparin, a Free-ion selective radiotracer extraction (FISRE) method has been used. (3) Results: AF4-MALS showed that radical depolymerization produces monodisperse EPSs, suitable for therapeutic use. EPS conformation exhibited a lower hydrodynamic volume for the highest ionic strengths. The resulting random-coiled conformation could affect the complexation with metal for high concentration. The LogK of Sc-EPS complexes have been determined and showing that they are comparable to the Sc-Hep. (4) Conclusions: EPSs are very promising to be coupled with the theranostic pair of scandium for Nuclear Medicine.

Human Chorionic Gonadotropin Polypeptide Nanoparticle Drug Delivery System Improves Methotrexate Efficacy in Gestational Trophoblastic Neoplasia in vitro

Purpose

To alleviate the sufferings of the chemotherapy patients, we developed a novel active targeted therapeutic system and showed its potential as a promising drug delivery strategy.

Methods

We utilized the human chorionic gonadotropin (HCG) ligand-receptor mediation to make an actively targeted drug delivery system with optimal HCG polypeptide fragment as target head base, polyethylene glycol–polylactic acid copolymers as nanometer materials to load chemotherapy drug methotrexate (MTX), to highly selectively deliver MTX into choriocarcinoma lesions, and to investigate the efficacy, targeting and tolerability of the complex in vitro experiments.

Results

Our data show that choriocarcinoma cell lines JEG-3 and JAR exhibited high expression levels of HCG receptor, peptide HCGβ81-95 specifically bonded to HCG receptor-positive cells and HCG81-NP efficiently delivered MTX to choriocarcinoma cells. HCG81-NP-MTX inhibited cell proliferation and reduced G₀/G₁ to S phase transition in JEG-3 and JAR cells.

Conclusion

We designed an active targeting therapy system of choriocarcinoma, significantly improved chemotherapy efficacy in vitro, and provided a theoretical basis for the treatment of malignant trophoblastic tumors.

A comparative study of antimicrobial activity of differently-synthesized chitosan nanoparticles against bovine mastitis pathogens

The greatest concern in dairy farming nowadays is bovine mastitis (BM), which results mainly from bacterial colonization of the mammary gland. Antibiotics are the most widely used strategy for its prevention and treatment, but overuse has led to growing antimicrobial resistance. Pathogens have also developed other mechanisms to persist in the udder, such as biofilm formation and internalization into bovine epithelial cells. New therapies are therefore needed to reduce or replace antibiotic therapies. In a previous study, we found that chitosan nanoparticles (Ch-NPs) have considerable potential for the treatment of BM. The aim of the present study was to evaluate the antimicrobial activity of differently-synthesized Ch-NPs against BM pathogens and their toxicity in bovine cells in vitro, to further explore the attributes of Ch-NPs for the prevention and treatment of intramammary infections. We also looked into their ability to inhibit biofilm formation and prevent the internalization of S. aureus into mammary epithelial cells. Finally, since an interesting approach for BM prevention is to enhance the host's immune response, we studied whether Ch-NPs could promote the release of pro-inflammatory cytokines in mammary epithelial cells. The results reveal that the bactericidal effect of Ch-NPs on BM pathogens and their ability to inhibit biofilm formation are size-dependent, with smaller particles being more efficient. In contrast, their effect on the viability of the cell lines is not size-dependent and all samples tested were non-toxic. The smallest Ch-NPs successfully prevented the internalization of S. aureus into the cells, but did not promote the production of pro-inflammatory cytokines. These findings make it possible to conclude that Ch-NPs are a great bactericidal agent which can prevent the main mechanisms developed by BM pathogens to persist in the udder.

pH-Sensitive silica-based core–shell nanogel prepared via RAFT polymerization: investigation of the core size effect on the release profile of doxorubicin

The novelty of this work is the synthesis of a core–shell nanogel that is based on silica nanoparticles as the core with different sizes via RAFT polymerization and its application to drug delivery.

Absorption, distribution, metabolism, and excretion of nanocarriers in vivo and their influences

As one of the most promising and effective delivery systems for targeted controlled-release drugs, nanocarriers (NCs) have been widely studied. Although the development of nanoparticle preparations is very prosperous, the safety and effectiveness of NCs are not guaranteed and cannot be precisely controlled due to the unclear processes of absorption, distribution, metabolism, and excretion (ADME), as well as the drug release mechanism of NCs in the body. Thus, the approval of NCs for clinical use is extremely rare. This paper reviews the research progress and challenges of using NCs in vivo based on a review of several hundred closely related publications. First, the ADME of NCs under different administration routes is summarized; second, the influences of the physical, chemical, and biosensitive properties, as well as targeted modifications of NCs on their disposal process, are systematically analyzed; third, the tracer technology related to the in vivo study of NCs is elaborated; and finally, the challenges and perspectives of nanoparticle research in vivo are introduced. This review may help readers to understand the current research progress and challenges of nanoparticles in vivo, as well as of tracing technology in nanoparticle research, to help researchers to design safer and more efficient NCs. Furthermore, this review may aid researchers in choosing or exploring more suitable tracing technologies to further advance the development of nanotechnology.

Low-Dose X-ray-Responsive Diselenide Nanocarriers for Effective Delivery of Anticancer Agents

X-ray-responsive nanocarriers for anticancer drug delivery have shown great promise for enhancing the efficacy of chemoradiotherapy. A critical challenge remains for development of such radiation-controlled drug delivery systems (DDSs), which is to minimize the required X-ray dose for triggering the cargo release. Herein, we design and fabricate an effective DDS based on diselenide block copolymers (as nanocarrier), which can be triggered to release their cargo with a reduced radiation dose of 2 Gy due to their sensitivity to both X-ray and the high level of reactive oxygen species (ROS) in the microenvironment of cancer cells. The underlying molecular mechanism is further illustrated by proton nuclear magnetic resonance (¹H NMR) experiments and density functional theory (DFT) calculations. In vivo experiments on tumor-bearing mice validated that the loaded drugs are effectively delivered to the tumor site and exert remarkable antitumor effects (minimum tumor volume/weight) along with X-ray. Furthermore, the diselenide nanocarriers exhibit no noticeable cytotoxicity. These findings provide new insights for the de novo design of radiation-controlled DDSs for cancer chemoradiotherapy.

Polymeric micelles for the delivery of poorly soluble drugs: From nanoformulation to clinical approval

Over the last three decades, polymeric micelles have emerged as a highly promising drug delivery platform for therapeutic compounds. Particularly, poorly soluble small molecules with high potency and significant toxicity were encapsulated in polymeric micelles. Polymeric micelles have shown improved pharmacokinetic profiles in preclinical animal models and enhanced efficacy with a superior safety profile for therapeutic drugs. Several polymeric micelle formulations have reached the clinical stage and are either in clinical trials or are approved for human use. This furthers interest in this field and underscores the need for additional learning of how to best design and apply these micellar carriers to improve the clinical outcomes of many drugs. In this review, we provide detailed information on polymeric micelles for the solubilization of poorly soluble small molecules in topics such as the design of block copolymers, experimental and theoretical analysis of drug encapsulation in polymeric micelles, pharmacokinetics of drugs in polymeric micelles, regulatory approval pathways of nanomedicines, and current outcomes from micelle formulations in clinical trials. We aim to describe the latest information on advanced analytical approaches for elucidating molecular interactions within the core of polymeric micelles for effective solubilization as well as for analyzing nanomedicine's pharmacokinetic profiles. Taking into account the considerations described within, academic and industrial researchers can continue to elucidate novel interactions in polymeric micelles and capitalize on their potential as drug delivery vehicles to help improve therapeutic outcomes in systemic delivery.