Biocompatible DNA/5-Fluorouracil-Gemini Surfactant-Functionalized Gold Nanoparticles as Promising Vectors in Lung Cancer Therapy

Long-chain cationic gemini surfactants as drug retention adjuvant on liposomes. A methodological approach with atorvastatin

This study delves into the development and characterization of dipalmitoyl phosphatidylcholine (DPPC) liposomes incorporated with gemini surfactant (tetradecamethylene-1,14 bis(dimethyl tetradecyl ammonium bromide); 14-14-14) and atorvastatin, aimed at enhancing drug delivery efficiency for cardiovascular diseases. The integration of gemini surfactants into liposomes is investigated for its potential to improve atorvastatin encapsulation and retention, addressing the drug's poor water solubility and the limitations of conventional liposomal systems. Through a combination of dynamic light scattering (DLS), differential scanning calorimetry (DSC), and molecular dynamics (MD) simulations, the study reveals that the presence of gemini surfactants significantly reduces liposome size and polydispersity, indicative of a more uniform and potentially unilamellar structure. DSC analysis highlights a decrease in transition temperatures and an alteration in transition symmetry, suggesting enhanced stability and a favourable drug release profile at physiological temperatures. MD simulations provide insight into the internalization mechanism of gemini surfactants and atorvastatin within the liposomal bilayer, demonstrating their mutual incorporation facilitated by polar interactions. Spectrophotometry-based retention studies further confirmed that liposomes containing gemini surfactants exhibit superior atorvastatin retention capabilities, nearly doubling the encapsulation efficiency compared to conventional liposomes. This research highlights the promising role of gemini surfactant-incorporated liposomes as an efficient drug delivery platform for cardiovascular therapeutics, offering insights into the molecular interactions and structural dynamics underlying their enhanced performance.

Pulmonary Delivery of Nonviral Nucleic Acid-Based Vaccines With Spotlight on Gold Nanoparticles

Nucleic acid-based vaccines are leading-edge tools in developing next-generation preventative care. Much research has been done to convert vaccine gene therapy from an invasive to a noninvasive administration approach. The lung's large surface area and permeability make the pulmonary route a promising noninvasive delivery option for vaccines, with systemic and local applications. This review summarizes the challenges and the approaches that have been carried out to optimize the delivery of nucleic acids through the pulmonary route for vaccination purposes in recent years, with a spotlight on gold nanoparticles (AuNPs). Nonviral delivery systems have been widely explored, and AuNPs with their unique properties are emerging as promising tools for nucleic acid vaccines due to surface functionalization with mucus-penetrating polymers and targeting moieties that can bypass the barriers in pulmonary delivery and successfully deliver nucleic acids to the cells of interest. However, while promising, several challenges remain including selectively overcoming the lungs' immunological surveillance and adhesive mucus.

Gemini surfactants as next-generation drug carriers in cancer management

INTRODUCTION

Gemini surfactants (GS) are an elite class of amphiphilic molecules that have shown up as a potential candidate in the field of drug delivery because of their exceptional physicochemical properties. They comprise two hydrophilic headgroups connected by an adaptable spacer and hydrophobic tails that has shown promising results in delivering different therapeutic agents to cancer cells at preclinical level. However further studies are in demand to unlock the full potential of GS in this field.

AREAS COVERED

This review summarizes the new advancements in GS as drug carriers in cancer therapy, their capacity to overcome conventional shortcomings and the demand for innovative approaches in disease treatment. A detailed list of GS-based formulations along with a brief description on oligomeric surfactants have also been provided in this review. This article summarizes data from studies identified through literature database searches including PubMed and Google Scholar (2010-2023).

EXPERT OPINION

There are major challenges that need to be addressed in this field which restrict their progression toward clinical phase. Further research can focus on developing a theranostic system that can provide simultaneous real-time monitoring along with treatment care. Nevertheless, ensuring the safety parameters of these nanocarriers followed by their regulatory approval is a time-consuming and expensive process. A collaborative approach between regulatory bodies, research institutions, and pharmaceutical companies can speed up the process in the upcoming years.

Tumor microenvironment-activated, immunomodulatory nanosheets loaded with copper(II) and 5-FU for synergistic chemodynamic therapy and chemotherapy

The tumor microenvironment (TME) has a redox state that differs greatly from normal tissues, as characterized by the overexpression of H2O2 and glutathione (GSH). To address the GSH-related restrictions on chemodynamic therapy (CDT) efficacy, we have developed a Cu(II)-based CDT strategy. In this study, a novel organic-inorganic hybrid drug delivery system (LDH/HA/5-FU) was conceived and prepared by the intercalation of 5-FU into the interlayer of copper-aluminum layered double hydroxide (CuAl-LDH) via ion exchange strategy and the adsorption of hyaluronic acid (HA) on the surface of CuAl-LDH. Taking advantage of the pH-degradable property of CuAl-LDH and the CD44-targeting property of HA, the formed LDH/HA/5-FU nanosheets could specifically target tumor cells' overexpressing CD44 receptor, rapidly release Cu(II) and 5-FU in tumor cells, inducing tumor cell apoptosis and cuproptosis, and long-term intracellular GSH depletion and toxic hydroxyl radicals (·OH) generation could be achieved through the cyclic catalytic reaction of Cu(I)/Cu(II). Meanwhile, peritumoral injection of LDH/HA/5-FU nanosheets might function as an adjuvant to increase the levels of antitumor tumor-associated macrophages (TAMs) and T cells. In vivo experiments further verified that the intelligently designed LDH/HA/5-FU nanosheets successfully promoted the immune systems, with an excellent inhibition efficacy towards tumors by combining Cu-based CDT and chemotherapy, showing promising potential for solid tumor treatments.

Synergistic Antibacterial Effects of Amoxicillin and Gold Nanoparticles: A Therapeutic Option to Combat Antibiotic Resistance

Compacted Au@16-mph-16/DNA-AMOX (NSi) nanosystems were prepared from amoxicillin (AMOX) and precursor Au@16-mph-16 gold nanoparticles (Ni) using a Deoxyribonucleic acid (DNA) biopolymer as a glue. The synthesized nanocarrier was tested on different bacterial strains of Escherichia coli, Staphylococcus aureus, and Streptococcus pneumoniae to evaluate its effectiveness as an antibiotic as well as its internalization. Synthesis of the nanosystems required previous structural and thermodynamic studies using circular dichroism (CD) and UV-visible techniques to guarantee optimal complex formation and maximal DNA compaction, characteristics which facilitate the correct uptake of the nanocarrier. Two nanocomplexes with different compositions and structures, denoted NS1 and NS2, were prepared, the first involving external Au@16-mph-16 binding and the second partial intercalation. The Ni and NSi nanosystems obtained were characterized via transmission electron microscopy (TEM), zeta potential, and dynamic light scattering (DLS) techniques to measure their charge, aggregation state and hydrodynamic size, and to verify their presence inside the bacteria. From these studies, it was concluded that the zeta potential values for gold nanoparticles, NS1, and NS2 nanosystems were 67.8, -36.7, and -45.1 mV. Moreover, the particle size distribution of the Au@16-mph-16 gold nanoparticles and NS2 nanoformulation was found to be 2.6 nm and 69.0 nm, respectively. However, for NS1 nanoformulation, a bimodal size distribution of 44 nm (95.5%) and 205 nm (4.5%) was found. Minimal inhibitory concentration (MIC) values were determined for the bacteria studied using a microdilution plates assay. The effect on Escherichia coli bacteria was notable, with MIC values of 17 µM for both the NS1 and NS2 nanosystems. The Staphylococcus aureus chart shows a greater inhibition effect of NS2 and NP2 in non-diluted wells, and clearly reveals a great effect on Streptococcus pneumoniae, reaching MIC values of 0.53 µM in more diluted wells. These results are in good agreement with TEM internalization studies of bacteria that reveal significant internalization and damage in Streptococcus pneumoniae. In all the treatments carried out, the antibiotic capacity of gold nanosystems as enhancers of amoxicillin was demonstrated, causing both the precursors and the nanosystems to act very quickly, and thus favoring microbial death with a small amount of antibiotic. Therefore, these gold nanosystems may constitute an effective therapy to combat resistance to antibiotics, in addition to avoiding the secondary effects derived from the administration of high doses of antibiotics.

Functionalized Metal Nanoparticles in Cancer Therapy

Currently, there are many studies on the application of nanotechnology in therapy. Metallic nanoparticles are promising nanomaterials in cancer therapy; however, functionalization of these nanoparticles with biomolecules has become relevant as their effect on cancer cells is considerably increased by photothermal and photodynamic therapies, drug nanocarriers, and specificity by antibodies, resulting in new therapies that are more specific against different types of cancer. This review describes studies on the effect of functionalized palladium, gold, silver and platinum nanoparticles in the treatment of cancer, these nanoparticles themselves show an anticancer effect. This effect is further enhanced when the NPs are functionalized with either antibodies, DNA, RNA, peptides, proteins, or folic acid and other molecules. These NPs can penetrate the cell and accumulate in the tumor tissue, resulting in a cytotoxic effect through the generation of ROS, the induction of apoptosis, cell cycle arrest, DNA fragmentation, and a photothermal effect. NP-based therapy is a new strategy that can be used synergistically with chemotherapy and radiotherapy to achieve more effective therapies and reduce side effects.

pH-Dependent Behavior of Novel 5-FU Delivery System in Environmental Conditions Comparable to the Gastro-Intestinal Tract

A biogenic carrier for 5-fluorouracil (5-FU) loading and subsequent tableting as a new drug formulation for slow release has been proposed using the biomineral from blue crab carapace. Due to its highly ordered 3D porous nanoarchitecture, the biogenic carbonate carrier could achieve increased effectiveness in colorectal cancer cure provided that the formulation would successfully pass through the gastric acid conditions. Following the recently proven viability of the concept by demonstrating the slow release of the drug from the carrier using the highly sensitive SERS technique, here we investigated the 5-FU release from the composite tablet drug in pH conditions replicating the gastric environment. The released drug from the tablet was studied in solutions with three relevant pH values, pH 2, pH 3, and pH 4. The 5-FU SERS spectral signature for each pH value was used to build calibration curves for quantitative SERS analysis. The results suggested a similarly slow-releasing pattern in acid pH environments to that in neutral conditions. Although biogenic calcite dissolution was expected in acid conditions, the X-ray diffraction and Raman spectroscopy showed preservation of calcite mineral along with the monohydrocalcite during acid solution exposure for two hours. The total released amount in a time course of seven hours, however, was lower in acidic pH solutions, with a maximum fraction of ~40% of the total amount of loaded drug, for pH 2, as opposed to ~80% for neutral values. Nonetheless, these results clearly prove that the novel composite drug retains its slow-releasing character in environmental conditions compatible with the gastrointestinal pH and that it is a viable and biocompatible alternative for oral delivery of anticancer drug to reach the lower gastro-intestinal tract.

Accumulation, Chronicity, and Induction of Oxidative Stress Regulating Genes Through Allium cepa L. Functionalized Silver Nanoparticles in Freshwater Common Carp (Cyprinus carpio)

Green evolutionary products such as biologically fabricated nanoparticles (NPs) pose a hazard to aquatic creatures. Herein, biogenic silver nanoparticles (AgNPs) were synthesized by the reaction between ionic silver (AgNO₃) and aqueous onion peel extract (Allium cepa L). The synthesized biogenic AgNPs were characterized with UV-Visible spectrophotometer, XRD, FT-IR, and TEM with EDS analysis; then, their toxicity was assessed on common carp fish (Cyprinus carpio) using biomarkers of haematological alterations, oxidative stress, histological changes, differential gene expression patterns, and bioaccumulation. The 96 h lethal toxicity was analysed with various concentrations (2, 4, 6, 8, and 10 mg/l) of biogenic AgNPs. Based on 96 h LC₅₀, sublethal concentrations (1/15^th, 1/10^th, and 1/5^th) were given to C. carpio for 28 days. At the end of experiment, the bioaccumulations of Ag content were accumulated mainly in the gills, followed by the liver and muscle. At an interval of 7 days, the haematological alterations showed significance (p < 0.05) and elevation of antioxidant defence mechanism reveals the toxicity of biogenic synthesized AgNPs. Adverse effects on oxidative stress were probably related to the histopathological damage of its vital organs like gill, liver, and muscle. Finally, the fish treated with biogenic synthesized AgNPs were significantly (p < 0.05) downregulates the oxidative stress genes such as Cu-Zn SOD, CAT, GPx1a, GST-α, CYP1A, and Nrf-2 expression patterns. The present study provides evidence of biogenic synthesized AgNPs influence on the aquatic life through induction of oxidative stress.

Gold Nanosystems Covered with Doxorubicin/DNA Complexes: A Therapeutic Target for Prostate and Liver Cancer

Different gold nanosystems covered with DNA and doxorubicin (Doxo) were designed and synthesized for cancer therapy, starting from Au@16-Ph-16 cationic nanoparticles and DNA-Doxo complexes prepared under saturation conditions. For the preparation of stable, biocompatible, and small-sized compacted Au@16-Ph-16/DNA-Doxo nanotransporters, the conditions for the DNA-Doxo compaction process induced by gold nanoparticles were first explored using fluorescence spectroscopy, circular dichroism and atomic force microscopy techniques. The reverse process, which is fundamental for Doxo liberation at the site of action, was found to occur at higher C_Au@16-Ph-16 concentrations using these techniques. Zeta potential, dynamic light scattering and UV-visible spectroscopy reveal that the prepared compacted nanosystems are stable, highly charged and of adequate size for the effective delivery of Doxo to the cell. This fact is verified by in vitro biocompatibility and internalization studies using two prostate cancer-derived cell lines (LNCaP and DU145) and one hepatocellular carcinoma-derived cell line (SNU-387), as well as a non-tumor prostate (PNT2) cell line and a non-hepatocarcinoma hepatoblastoma cell line (Hep-G2) model used as a control in liver cells. However, the most outstanding results of this work are derived from the use of the C_I+N_I combined treatments which present strong action in cancer-derived cell lines, while a protective effect is observed in non-tumor cell lines. Hence, novel therapeutic targets based on gold nanoparticles denote high selectivity compared to conventional treatment based on free Doxo at the same concentration. The results obtained show the viability of both the proposed methodology for internalization of compacted nanocomplexes inside the cell and the effectiveness of the possible treatment and minimization of side effects in prostate and liver cancer.

Facile approach for surfactant-free synthesis of Au@ginsenoside Rh2 nanoparticles and researches on anticancer activity

Background

Inorganic nanocomposites especially Au nanostructures have exhibited outstanding physicochemical properties in biomedical fields. For further clinical applications on theranostics, especially drug delivery, numerous explorations of green and facile synthesis methods combining with pharmacoactive natural components have been investigated to construct safe and multifunctional bioactive Au nanoparticles (NPs). Ginsenoside Rh2 is protopanaxadiol type compound isolated from plants of genus Panax, with excellent anticancer effect and antioxidant activity. In this research, we prepared the novel Au nanoparticles using ginsenoside Rh2 as both reducing and stabilizing agents.

Results

The synthesized Au@ginsenoside Rh2 NPs were proved to exhibit desirable inhibitory effect on different cancer cell lines, which benefited from the inherent anticancer effect of the ginsenoside Rh2. Investigations in vitro indicated that Au@ginsenoside Rh2 NPs inhibited cell proliferation, cell migration and invasion, induced cell cycle arrest, enhanced the reactive oxygen species (ROS) generation, and regulated the protein expressions of caspase-3, 8, 9 to trigger cell apoptosis as well.

Conclusions

Because of the absence of toxic chemical surfactants, the eco-friendly synthesis method of Au NPs modified by natural phytochemicals avoided tedious separation and modification processes. On the other hand, Au@ginsenoside Rh2 NPs also improved water solubility and bioavailability of the hydrophobic drug ginsenoside Rh2. It broadened minds for preparation and application of traditional Chinese medicines (TCMs) modified metal nanoparticles and deserved further study.

Use of Nanoparticles to Prevent Resistance to Antibiotics-Synthesis and Characterization of Gold Nanosystems Based on Tetracycline

Antimicrobial resistance (AMR) is a serious public health problem worldwide which, according to the World Health Organization (WHO), requires research into new and more effective drugs. In this work, both gold nanoparticles covered with 16-3-16 cationic gemini surfactant (Au@16-3-16) and DNA/tetracycline (DNA/TC) intercalated complexes were prepared to effectively transport tetracycline (TC). Synthesis of the Au@16-3-16 precursor was carried out by using trihydrated gold, adding sodium borohydride as a reducing agent and the gemini surfactant 16-3-16 as stabilizing agent. Circular dichroism and atomic force microscopy techniques were then used to ascertain the optimal R range of the relationship between the concentrations of Au@16-3-16 and the DNA/TC complex (R = CAu@16-3-16/CDNA) that allow the obtainment of stable and compact nanosystems, these characteristics being fundamental for their use as antibiotic transporters. Stability studies over time were carried out for distinct selected Au@16-3-16 and Au@16-3-16/DNA-TC nanoformulations using the ultraviolet−visible spectrophotometry technique, checking their stability for at least one month. In addition, in order to know the charge and size distribution of the nanocomplexes, DLS and zeta potential measurements were performed in the solution. The results showed that the characterized nanosystems were highly charged, stable and of a reduced size (<100 nm) that allows them to cross bacterial membranes effectively (>1 μm). Once the different physicochemical characteristics of the gold nanosystems were measured, Au@16-3-16 and Au@16-3-16/DNA-TC were tested on Escherichia coli and Staphylococcus aureus to study their antibacterial properties and internalization capacity in microbes. Differences in the interaction of the precursors and the compacted nanosystems generated were observed in Gram-positive and Gram-negative bacteria, possibly due to membrane damage or electrostatic interaction with internalization by endocytosis. In the internalization experiments, depending on the treatment application time, the greatest bacterial destruction was observed for all nanoformulations explored at 18 h of incubation. Importantly, the results obtained demonstrate that both new nanosystems based on TC and Au@16-3-16 precursors have optimal antimicrobial properties and would be beneficial for use in patients, avoiding possible side effects.