Gold nanorod-loaded (PLGA-PEG) nanocapsules as near-infrared controlled release model of anticancer therapeutics

Novel thymohydroquinone gallate derivative loaded ligand modified quantum dots as pH-sensitive multi-modal theragnostic agent for cancer treatment

BACKGROUND

Nanomedicine, as the combination of radiopharmaceutical and nanocarrier (QDs), is developed for treating cancer. Gallic acid is antimutagenic, anti-inflammatory, and anti-carcinogenic. Typical retention time of gallic acid is approximately 4 to 8 h. To increase the retention time gallic acid is converted to prodrug by adding lipophilic moieties, encapsulating in lipophilic nanoparticles, or liposome formation. Similarly, thymoquinone is powerful antioxidant, anti-apoptotic, and anti-inflammatory effect, with reduced DNA damage.

METHODS

In this study, a hydrophilic drug (gallic acid) is chemically linked to the hydrophobic drug (thymohydroquinone) to overcome the limitations of co-delivery of drugs. Thymohydroquinone (THQG) as the combination of gallic acid (GA) and thymoquinone (THQ) is loaded onto the PEI functionalized antimonene quantum dots (AM-QDs) and characterized by FTIR, UV-visible spectroscopy, X-ray powder diffraction, Zeta sizer, SEM and AFM, in-vitro and in-vivo assay, and hemolysis.

RESULTS

The calculated drug loading efficiency is 90 %. Drug release study suggests the drug combination is pH sensitive and it can encounters acidic pH, releasing the drug from the nanocarrier. The drug and drug-loaded nanocarrier possesses low cytotoxicity and cell viability on MCF-7 and Cal-27 cell lines. The proposed drug delivery system is radiolabeled with Iodine-131 (131I) and Technetium (99mTc) and its deposition in various organs of rats' bodies is examined by SPECT-CT and gamma camera. Hemolytic activity of 2, 4, 6, and 8 μg/mL is 1.78, 4.16, 9.77, and 15.79 %, respectively, reflecting low levels of hemolysis. The system also sustains oxidative stress in cells and environment, decreasing ROS production to shield cells and keep them healthy.

CONCLUSIONS

The results of this study suggest that the proposed drug carrier system can be used as a multi-modal theragnostic agent in cancer treatment.

Ephedra intermedia Schrenk & C. A. Mey Methanol Extract: Nanoencapsulation by Mini-Emulsion Polymerization and its Release Trend under Simulated Conditions of the Human Body

In this research, the extract of Ephedra intermedia Schrenk & C.A.Mey. was encapsulated using the mini-emulsion polymerization method based on methyl methacrylate polymers with a nanometer size. The encapsulated extract was characterized using different analytical techniques. Furthermore, the loading efficiency and release of the plant extract were examined. FT-IR spectroscopy confirmed the formation of an expectational product. The TEM and SEM imaging showed a spherical morphology for the prepared encapsulated extract. The average size of poly-methyl-methacrylate nanoparticles containing Ephedra extract was found to be approximately 47 nm. The extract loading efficiency and encapsulation efficiency test demonstrated a dose-depending behavior on E. intermedia extract for both analyses, which is highly advantageous for traversing biological barriers. The release assay shows a controlled release for the extract at phosphate buffer solution (PBS). A 38 % release was calculated after 36 hours. The results obtained from the present study reveal that encapsulating the plant extract is a suitable alternative to control and increase their medicinal properties.

Meta-Analysis of Nanoparticle Distribution in Tumors and Major Organs in Tumor-Bearing Mice

Low tumor delivery efficiency is a critical barrier in cancer nanomedicine. This study reports an updated version of "Nano-Tumor Database", which increases the number of time-dependent concentration data sets for different nanoparticles (NPs) in tumors from the previous version of 376 data sets with 1732 data points from 200 studies to the current version of 534 data sets with 2345 data points from 297 studies published from 2005 to 2021. Additionally, the current database includes 1972 data sets for five major organs (i.e., liver, spleen, lung, heart, and kidney) with a total of 8461 concentration data points. Tumor delivery and organ distribution are calculated using three pharmacokinetic parameters, including delivery efficiency, maximum concentration, and distribution coefficient. The median tumor delivery efficiency is 0.67% injected dose (ID), which is low but is consistent with previous studies. Employing the best regression model for tumor delivery efficiency, we generate hypothetical scenarios with different combinations of NP factors that may lead to a higher delivery efficiency of >3%ID, which requires further experimentation to confirm. In healthy organs, the highest NP accumulation is in the liver (10.69%ID/g), followed by the spleen 6.93%ID/g and the kidney 3.22%ID/g. Our perspective on how to facilitate NP design and clinical translation is presented. This study reports a substantially expanded "Nano-Tumor Database" and several statistical models that may help nanomedicine design in the future.

Pharmacokinetics and tumor delivery of nanoparticles

Nanoparticles (NPs) have been widely used in different areas, including consumer products and medicine. In terms of biomedical applications, NPs or NP-based drug formulations have been extensively investigated for cancer diagnostics and therapy in preclinical studies, but the clinical translation rate is low. Therefore, a thorough and comprehensive understanding of the pharmacokinetics of NPs, especially in drug delivery efficiency to the target therapeutic tissue tumor, is important to design more effective nanomedicines and for proper assessment of the safety and risk of NPs. This review article focuses on the pharmacokinetics of both organic and inorganic NPs and their tumor delivery efficiencies, as well as the associated mechanisms involved. We discuss the absorption, distribution, metabolism, and excretion (ADME) processes following different routes of exposure and the mechanisms involved. Many physicochemical properties and experimental factors, including particle type, size, surface charge, zeta potential, surface coating, protein binding, dose, exposure route, species, cancer type, and tumor size can affect NP pharmacokinetics and tumor delivery efficiency. NPs can be absorbed with varying degrees following different exposure routes and mainly accumulate in liver and spleen, but also distribute to other tissues such as heart, lung, kidney and tumor tissues; and subsequently get metabolized and/or excreted mainly through hepatobiliary and renal elimination. Passive and active targeting strategies are the two major mechanisms of tumor delivery, while active targeting tends to have less toxicity and higher delivery efficiency through direct interaction between ligands and receptors. We also discuss challenges and perspectives remaining in the field of pharmacokinetics and tumor delivery efficiency of NPs.

Coiled-coil peptide-based assembly of a plasmonic core-satellite polymer-metal nanocomposite as an efficient photothermal agent for drug delivery applications

Polymer-metal nanocomposites have widespread applications in biomedical fields such as imaging, catalysis, and drug delivery. These particles are characterized by combined organic and inorganic properties. Specifically, photothermal nanocomposites incorporating polymeric and plasmonic nanoparticles (NPs) have been designed for both triggered drug release and as imaging agents. However, the usual design of nanocomposites confers characteristic issues, among which are the decrease of optical properties and resulting low photothermal efficiency, as well as interactions with loaded drugs. Herein, we report the design of a core-satellite polymer-metal nanocomposite assembled by coiled-coil peptides and its superior photothermal efficiency compared to electrostatic-driven nanocomposites which is the standard design. We also found that the orientation of gold nanorods on the surface of polymeric NPs is of importance in the final photothermal efficiency and could be exploited for various applications. Our findings provide an alternative to current wrapping and electrostatic assembly of nanocomposites with the help of coiled-coil peptides and an improvement of the control over core-satellite assemblies with plasmonic NPs. It paves the way to highly versatile assemblies due to the nature of coiled-coil peptides to be easily modified and sensitive to pH or temperature.

A novel gold-polymer-antibody conjugate for targeted (radio-photothermal) treatment of HepG2 cells

Localization of the near-infrared (NIR) plasmonic nanoparticles at the tumor sites is essential for safe and efficient photothermal therapy of cancer. In this work, two biocompatible polymers: modified poly(ethylene glycol) (PEG) and branched polyethyleneimine (bPEI) were used to bind plasmonic hollow gold nanospheres (HAuNS) to the tumor-specific antibody, atezolizumab (ATZ). The photo-immunoconjugate (HAuNS-PEI-PEG-ATZ) was prepared via a simple and cost-effective procedure. The conjugate was also prepared with the radioiodinated antibody (ATZ-¹³¹I) to combine the targeted radio- and photothermal cytotoxic actions against human hepatoma (HepG2) cells. In vitro study revealed that attachment to the antibody and the use of cellular internalizing polymers enhanced the cellular localization of both gold and the radiotherapeutic Iodine-131. Compared to bare gold nanoparticles, (HAuNS-PEI-PEG-ATZ) conjugate exhibited a significantly enhanced photothermal ablation of HepG2 cells after laser irradiation (0.4 W cm^-2, 5 min). Laser irradiation of the cells treated with the radiolabeled conjugate (HAuNS-PEI-PEG-ATZ-¹³¹I) exhibited the highest cytotoxicity against HepG2 cells due to the combinatorial cytotoxic effects.

Pyrazole derivatives as potent EGFR inhibitors: synthesis, biological evaluation and in silico and biodistribution study

Aim: Synthesis of pyrazole derivatives as EGFR inhibitors. Materials & methods: Cytotoxicity and EGFR inhibitory effect were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and EGFR kits, respectively. The biodistribution of radioiodinated compound nanoparticles in tumor-bearing mice was studied. Results: The IC₅₀ values of compound 4a against HepG2 cells and EGFR were 0.15 ± 0.03 and 0.31 ± 0.008 μM, respectively, while those of erlotinib were 0.73 ± 0.04 and 0.11 ± 0.008 μM, respectively. The binding scores of compound 4a and erlotinib to EGFR were -9.52 and -10.23 Kcal/mol, respectively. The maximum tumor uptake of radioiodinated compound after intravenous nanoparticle injection was 6.7 ± 0.3% radioactivity/g. Conclusion: Compound 4a is a promising antitumor agent with a potential EGFR inhibitory effect.

Advances in biomaterials for the treatment of retinoblastoma

Retinoblastoma is the most common primary intraocular malignancy in children. Although traditional chemotherapy has shown some success in retinoblastoma management, there are several shortcomings to this approach, including inadequate pharmacokinetic parameters, multidrug resistance, low therapeutic efficiency, nonspecific targeting, and the need for adjuvant therapy, among others. The revolutionary developments in biomaterials for drug delivery have enabled breakthroughs in cancer management. Today, biomaterials are playing a crucial role in developing more efficacious retinoblastoma treatments. The key goal in the evolution of drug delivery biomaterials for retinoblastoma therapy is to resolve delivery-associated obstacles and lower nonlocal exposure while ameliorating certain adverse effects. In this review, we will first delve into the historical perspective of retinoblastoma with a focus on the classical treatments currently used in clinics to enhance patients' quality of life and survival rate. As we move along, we will discuss biomaterials for drug delivery applications. Various aspects of biomaterials for drug delivery will be dissected, including their features and recent advances. In accordance with the current advances in biomaterials, we will deliver a synopsis on the novel chemotherapeutic drug delivery strategies and evaluate these approaches to gain new insights into retinoblastoma treatment.

Surface modifications of Gold Nanoparticles: Stabilization and Recent Applications in Cancer Therapy

Gold nanoparticles (GNP) are noble metal nanocarriers that have been recently researched upon for pharmaceutical applications, imaging, and diagnosis. These metallic nanocarriers are easy to synthesize using chemical reduction techniques as their surface can be easily modified. Also, the properties of GNP are significantly affected by its size and shape which mandates its stabilization using suitable techniques of surface modification. Over the past decade, research has focused on surface modification of GNP and its stabilization using polymers, polysaccharides, proteins, dendrimers, and phase-stabilizers like gel phase or ionic liquid phase. The use of GNP for pharmaceutical applications requires its surface modification using biocompatible and inert surface modifiers. The stabilizers used, interact with the surface of GNP to provide either electrostatic stabilization or steric stabilization. This review extensively discusses the surface modification techniques for GNP and the related molecular level interactions involved in the same. The influence of various factors like the concentration of stabilizers used their characteristics like chain length and thickness, pH of the surrounding media, etc., on the surface of GNP and resulting to stability have been discussed in detail. Further, this review highlights the recent applications of surface-modified GNP in the management of tumor microenvironment and cancer therapy.

Identification of a Unique Cytotoxic Thieno[2,3-c]Pyrazole Derivative with Potent and Selective Anticancer Effects In Vitro

In recent years, the thienopyrazole moiety has emerged as a pharmacologically active scaffold with antitumoral and kinase inhibitory activity. In this study, high-throughput screening of 2000 small molecules obtained from the ChemBridge DIVERset library revealed a unique thieno[2,3-c]pyrazole derivative (Tpz-1) with potent and selective cytotoxic effects on cancer cells. Compound Tpz-1 consistently induced cell death at low micromolar concentrations (0.19 μM to 2.99 μM) against a panel of 17 human cancer cell lines after 24 h, 48 h, or 72 h of exposure. Furthermore, an in vitro investigation of Tpz-1's mechanism of action revealed that Tpz-1 interfered with cell cycle progression, reduced phosphorylation of p38, CREB, Akt, and STAT3 kinases, induced hyperphosphorylation of Fgr, Hck, and ERK 1/2 kinases, and disrupted microtubules and mitotic spindle formation. These findings support the continued exploration of Tpz-1 and other thieno[2,3-c]pyrazole-based compounds as potential small-molecule anticancer agents.

Biocompatible mucoadhesive nanoparticles for brain targeting of ropinirole hydrochloride: Formulations, radiolabeling and biodistribution

Two nanoformulations with mucoadhesive properties and brain-targeting mechanisms were designed to deliver the anti-Parkinson's drug, ropinirole hydrochloride (RH). In the first formulation, RH and the amphiphilic block copolymer methoxy poly(ethylene glycol)-b-poly(caprolactone) were assembled in a core-shell morphology followed by coating with a mucoadhesive chitosan outer layer producing a multilayer vehicle (MLV). In the second formulation, RH was encapsulated during the polyelectrolyte complexation of two natural polymers, chitosan and alginate producing RH-loaded chitosan-alginate polyelectrolyte (PEC) nanocomplex. Conditions of each formulation were adopted for optimal drug loading. Physico-chemical characterization of the prepared formulations (particle size, polydispersity index and zeta-potential) exhibited stable monodispersed nanoparticles. RH was radiolabeled by I-131 radiotracer in a high-radiochemical yield. Biodistribution and brain targeting of RH from the prepared formulations were studied after administration of ¹³¹ I-RH-loaded nanoparticles to albino mice via intranasal and intravenous routs. Elevated brain radioactivity was detected post IN administration of (¹³¹ I-RH/PCL-PEG/CS) nanoparticles and (¹³¹ I-RH/CS-ALG) nanoparticles comparing with the IN administrated RH solutions (C_max  = 2.8 ± 0.3, 2 ± 0.3, 0.93 ± 0.03% radioactivity/g, 1 h post administration, respectively). This demonstrated that a relatively high-brain targeting could be achieved via intranasal route of administration of RH-loaded nanoparticles. The proposed models are further potential for application to deliver many other brain-targeting therapeutics.

K, Pilaquinga F, Kumar B, Debut A. Comparative statistical analysis of the release kinetics models for nanoprecipitated drug delivery systems based on poly(lactic-co-glycolic acid)

Poly(lactic-co-glycolic acid) is one of the most used polymers for drug delivery systems (DDSs). It shows excellent biocompatibility, biodegradability, and allows spatio-temporal control of the release of a drug by altering its chemistry. In spite of this, few formulations have reached the market. To characterize and optimize the drug release process, mathematical models offer a good alternative as they allow interpreting and predicting experimental findings, saving time and money. However, there is no general model that describes all types of drug release of polymeric DDSs. This study aims to perform a statistical comparison of several mathematical models commonly used in order to find which of them best describes the drug release profile from PLGA particles synthesized by nanoprecipitation method. For this purpose, 40 datasets extracted from scientific articles published since 2016 were collected. Each set was fitted by the models: order zero to fifth order polynomials, Korsmeyer-Peppas, Weibull and Hyperbolic Tangent Function. Some data sets had few observations that do not allow to apply statistic test, thus bootstrap resampling technique was performed. Statistic evidence showed that Hyperbolic Tangent Function model is the one that best fit most of the data.

Co-delivery of quercetin and caffeic-acid phenethyl ester by polymeric nanoparticles for improved antitumor efficacy in colon cancer cells

AIM

This study aimed to synthesise quercetin- caffeic-acid phenethyl ester (CAPE)-co-loaded poly(lactic-co-glycolic-acid) (PLGA) nanoparticles (QuCaNP) and investigate their anti-cancer activity on human colorectal carcinoma HT-29 cells.

METHODS

QuCaNPs were synthesised using single-emulsion (o/w) solvent evaporation method. Particle size, zeta potential, polydispersity index, in vitro release profile, and surface morphology of QuCaNPs were determined. Cytotoxicity, anti-migration, anti-proliferation and apoptotic activities of QuCaNPs were studied.

RESULTS

Mean diameter of QuCaNP was 237.8 ± 9.670 nm, with a polydispersity index (PDI) of 0.340 ± 0.027. Encapsulation efficiency was 74.28% (quercetin) and 65.24% (CAPE). Particle size and drug content of QuCaNP remained stable for 30 days at -20 °C. The half-maximal inhibitory concentration (IC₅₀) values of QuCaNP-treated HT-29 cells were calculated as 11.2 µg/mL (24 h) and 8.2 µg/mL (48 h). QuCaNP treatment increased mRNA levels of caspase-3 (2.38 fold) and caspase-9 (2-fold) and expressions of key proteins in the intrinsic apoptosis pathway in HT-29 cells.

CONCLUSION

Overall, our results demonstrated QuCaNPs exhibits improved anti-cancer activity on HT-29 cells.

Preventing Memory Effects in Surface-Enhanced Raman Scattering Substrates by Polymer Coating and Laser-Activated Deprotection

The development of continuous monitoring systems requires in situ sensors that are capable of screening multiple chemical species and providing real-time information. Such in situ measurements, in which the sample is analyzed at the point of interest, are hindered by underlying problems derived from the recording of successive measurements within complex environments. In this context, surface-enhanced Raman scattering (SERS) spectroscopy appears as a noninvasive technology with the ability of identifying low concentrations of chemical species as well as resolving dynamic processes under different conditions. To this aim, the technique requires the use of a plasmonic substrate, typically made of nanostructured metals such as gold or silver, to enhance the Raman signal of adsorbed molecules (the analyte). However, a common source of uncertainty in real-time SERS measurements originates from the irreversible adsorption of (analyte) molecules onto the plasmonic substrate, which may interfere in subsequent measurements. This so-called "SERS memory effect" leads to measurements that do not accurately reflect varying conditions of the sample over time. We introduce herein the design of plasmonic substrates involving a nonpermeable poly(lactic-co-glycolic acid) (PLGA) thin layer on top of the plasmonic nanostructure, toward controlling the adsorption of molecules at different times. The polymeric layer can be locally degraded by irradiation with the same laser used for SERS measurements (albeit at a higher fluence), thereby creating a micrometer-sized window on the plasmonic substrate available to molecules present in solution at a selected measurement time. Using SERS substrates coated with such thermolabile polymer layers, we demonstrate the possibility of performing over 10,000 consecutive measurements per substrate as well as accurate continuous monitoring of analytes in microfluidic channels and biological systems.

99mTc radiolabeling of polyethylenimine capped carbon dots for tumor targeting: synthesis, characterization and biodistribution

PURPOSE

Due to the favorable physicochemical properties and the biocompatibility, carbon dots (CDs) have gained a great attention as a tumor targeting agent. This study investigates polyethylenimine capped CDs (PEI capped CDs) as a prospective nanocarrier of technetium-99m (99mTc) for tumor targeting. Technetium-labeled CDs could be introduced as a promising candidate for single photon emission tomography (SPECT) imaging.

MATERIALS AND METHODS

Polyethylenimine capped CDs were prepared by hydrothermal method using hyperbranched PEI and citric acid. For a purpose of comparison, citrate capped CDs were also prepared by microwave irradiation. Both types of CDs were characterized and radiolabeled with 99mTc using sodium borohydride (NaBH4) as a reducing agent. Biodistribution and tumor targeting efficiency of the produced radiolabeled CDs have been studied in Earlich ascites tumor mice model.

RESULTS

Citrate capped CDs and PEI capped CDs have been synthesized successfully and characterized. High radiochemical yield of 99mTc-citrate capped CDs 99mTc-PEI capped CDs was obtained (97 ± 0.7 and 90 ± 0.2, respectively). Biodistribution studies of 99mTc-labeled PEI capped CDs have shown a potential tumor uptake (10 ± 0.5% Radioactivity/gram tumor) with high target to non-target ratio (T/NT) around 7 at 1-h post injection. 99mTc-citrate capped CDs have achieved a lower tumor uptake level (3.8 ± 0.3% Radioactivity/gram tumor 1 h post injection).

CONCLUSION

This study introduces PEI capped CDs as a promising nanocarrier of 99mTc for efficient tumor targeting. Technetium-labeled PEI capped CDs could be utilized as a potential SPECT tumor imaging agent.

PLGA Nanoparticle-Based Formulations to Cross the Blood-Brain Barrier for Drug Delivery: From R&D to cGMP

The blood–brain barrier (BBB) is a natural obstacle for drug delivery into the human brain, hindering treatment of central nervous system (CNS) disorders such as acute ischemic stroke, brain tumors, and human immunodeficiency virus (HIV)-1-associated neurocognitive disorders. Poly(lactic-co-glycolic acid) (PLGA) is a biocompatible polymer that is used in Food and Drug Administration (FDA)-approved pharmaceutical products and medical devices. PLGA nanoparticles (NPs) have been reported to improve drug penetration across the BBB both in vitro and in vivo. Poly(ethylene glycol) (PEG), poly(vinyl alcohol) (PVA), and poloxamer (Pluronic) are widely used as excipients to further improve the stability and effectiveness of PLGA formulations. Peptides and other linkers can be attached on the surface of PLGA to provide targeting delivery. With the newly published guidance from the FDA and the progress of current Good Manufacturing Practice (cGMP) technologies, manufacturing PLGA NP-based drug products can be achieved with higher efficiency, larger quantity, and better quality. The translation from bench to bed is feasible with proper research, concurrent development, quality control, and regulatory assurance.