In vivo evaluation of toxicity and anti-inflammatory activity of iron oxide nanoparticles conjugated with ibuprofen

Composite Hydrogels with Embedded Silver Nanoparticles and Ibuprofen as Wound Dressing

The wound healing process is often slowed down as a result of complications from bacterial infections and inflammatory reactions. Therefore, it is necessary to develop dressings with fast antibacterial and anti-inflammatory activity that shorten the wound healing period by promoting cell migration and proliferation. Chitosan (CS)-based hydrogels have been widely studied for their antibacterial and wound healing capabilities. Herein, we developed a composite hydrogel based on CS and PVA embedding silver nanoparticles (AgNPs) with antibacterial properties and ibuprofen (Ib) as an anti-inflammatory agent. The hydrogel prepared by double physical cross-linking, with oxalic acid and by freeze-thawing, loaded with 0.225 wt.% AgNPs and 0.264 wt.% Ib, displayed good mechanical properties (compressive modulus = 132 kPa), a high swelling degree and sustained drug delivery (in simulated skin conditions). Moreover, the hydrogel showed strong antibacterial activity against S. aureus and K. pneumoniae due to the embedded AgNPs. In vivo, this hydrogel accelerated the wound regeneration process through the enhanced expression of TNF alpha IP8, by activating downstream cascades and supporting the healing process of inflammation; Cox2, which enhances the migration and proliferation of cells involved in re-epithelization and angiogenesis; MHCII, which promotes immune cooperation between local cells, eliminating dead tissue and controlling infection; the intense expression of Col I as a major marker in the tissue granulation process; and αSMA, which marks the presence of myofibroblasts involved in wound closure and indicates ongoing re-epithelization. The results reveal the potential healing effect of CS/PVA/AgNPs/Ib hydrogels and suggest their potential use as wound dressings.

One Pot Synthesis, Biological Efficacy of AuNPs and Au-Amoxicillin Conjugates Functionalized with Crude Flavonoids Extract of Micromeria biflora

Amoxicillin is the most widely used antibiotic in human medicine for treating bacterial infections. However, in the present research, Micromeria biflora's flavonoids extract mediated gold nanoparticles (AuNPs) were conjugated with amoxicillin (Au-amoxi) to study their efficacy against the inflammation and pain caused by bacterial infections. The formation of AuNPs and Au-amoxi conjugates were confirmed by UV-visible surface plasmon peaks at 535 nm and 545 nm, respectively. The scanning electron microscopy (SEM), zeta potential (ZP), and X-ray diffraction (XRD) studies reveal that the size of AuNPs and Au-amoxi are found to be 42 nm and 45 nm, respectively. Fourier-transform infrared spectroscopy (FT-IR) absorption bands at 3200 cm^-1, 1000 cm^-1, 1500 cm^-1, and 1650 cm^-1 reveal the possible involvement of different moieties for the formation of AuNPs and Au-amoxi. The pH studies show that AuNPs and Au-amoxi conjugates are stable at lower pH. The carrageenan-induced paw edema test, writhing test, and hot plate test were used to conduct in vivo anti-inflammatory and antinociceptive studies, respectively. According to in vivo anti-inflammatory activity, Au-amoxi compounds have higher efficiency (70%) after 3 h at a dose of 10 mg/kg body weight as compared to standard diclofenac (60%) at 20 mg/kg, amoxicillin (30%) at 100 mg/kg, and flavonoids extract (35%) at 100 mg/kg. Similarly, for antinociceptive activities, writhing test results show that Au-amoxi conjugates produced the same number of writhes (15) but at a lower dose (10 mg/kg) compared to standard diclofenac (20 mg/kg). The hot plate test results demonstrate that the Au-amoxi has a better latency time of 25 s at 10 mg/kg dose when compared to standard Tramadol of 22 s at 30 mg/ kg, amoxicillin of 14 s at 100 mg/kg, and extract of 14 s at 100 mg/kg after placing the mice on the hot plate for 30, 60, and 90 min with a significance of (p ≤ 0.001). These findings show that the conjugation of AuNPs with amoxicillin to form Au-amoxi can boost its anti-inflammatory and antinociceptive potential caused by bacterial infections.

Where Is Nano Today and Where Is It Headed? A Review of Nanomedicine and the Dilemma of Nanotoxicology

Worldwide nanotechnology development and application have fueled many scientific advances, but technophilic expectations and technophobic demands must be counterbalanced in parallel. Some of the burning issues today are the following: (1) Where is nano today? (2) How good are the communication and investment networks between academia/research and governments? (3) Is there any spotlight application for nanotechnology? Nanomedicine is a particular arm of nanotechnology within the healthcare landscape, focused on diagnosis, treatment, and monitoring of emerging (such as coronavirus disease 2019, COVID-19) and contemporary (including diabetes, cardiovascular diseases, neurodegenerative disorders, and cancer) diseases. However, it may only represent the bright side of the coin. In fact, in the recent past, the concept of nanotoxicology has emerged to address the dark shadows of nanomedicine. The nanomedicine field requires more nanotoxicological studies to identify undesirable effects and guarantee safety. Here, we provide an overall perspective on nanomedicine and nanotoxicology as central pieces of the giant puzzle of nanotechnology. First, the impact of nanotechnology on education and research is highlighted, followed by market trends and scientific output tendencies. In the next section, the nanomedicine and nanotoxicology dilemma is addressed through the interplay of in silico, in vitro, and in vivo models with the support of omics and microfluidic approaches. Lastly, a reflection on the regulatory issues and clinical trials is provided. Finally, some conclusions and future perspectives are proposed for a clearer and safer translation of nanomedicines from the bench to the bedside.

Wide visible-range activatable fluorescence ZnSe:Eu3+/Mn2+@ZnS quantum dots: local atomic structure order and application as a nanoprobe for bioimaging

The development of QDs-based fluorescent bionanoprobe for cellular imaging fundamentally relies upon the precise knowledge of particle-cell interaction, optical properties of QDs inside and outside of the cell, movement of a particle in and out of the cell, and the fate of particle. We reported engineering and physicochemical characterization of water-dispersible Eu³⁺/Mn²⁺ co-doped ZnSe@ZnS core/shell QDs and studied their potential as a bionanoprobe for biomedical applications, evaluating their biocompatibility, fluorescence behaviour by CytoViva dual mode fluorescence imaging, time-dependent uptake, endocytosis and exocytosis in RAW 264.7 macrophages. The oxidation state and local atomic structure of the Eu dopant studied by X-ray absorption fine structure (XAFS) analysis manifested that the Eu³⁺ ions occupied sites in both ZnSe and ZnS lattices for the core/shell QDs. A novel approach was developed to relieve the excitation constraint of wide bandgap ZnSe by co-incorporation of Eu³⁺/Mn²⁺ codopants, enabling the QDs to be excited at a wide UV-visible range. The QDs displayed tunable emission colors by a gradual increase in Eu³⁺ concentration at a fixed amount of Mn²⁺, systematically enhancing the Mn²⁺ emission intensity via energy transfer from the Eu³⁺ to Mn²⁺ ion. The ZnSe:Eu³⁺/Mn²⁺@ZnS QDs presented high cell viability above 85% and induced no cell activation. The detailed analyses of QDs-treated cells by dual mode fluorescence CytoViva microscopy confirmed the systematic color-tunable fluorescence and its intensity enhances as a function of incubation time. The QDs were internalized by the cells predominantly via macropinocytosis and other lipid raft-mediated endocytic pathways, retaining an efficient amount for 24 h. The unique color tunability and consistent high intensity emission make these QDs useful for developing a multiplex fluorescent bionanoprobe, activatable in wide-visible region.

Green Fabrication and Release Mechanisms of pH-Sensitive Chitosan-Ibuprofen Aerogels for Controlled Transdermal Delivery of Ibuprofen

Ibuprofen is a potent non-steroidal anti-inflammatory drug due to its analgesic, antipyretic, and anti-inflammatory actions. However, its poor solubility in water makes it difficult to manufacture ibuprofen tablets, which limited the application of ibuprofen in drug delivery systems. Polymer–drug aerogels have attracted huge interest in optimizing the drug delivery efficiency and improving the physicochemical characteristics and therapeutic quality. Here, chitosan–ibuprofen aerogels with excellent swelling, high biocompatibility, and better drug delivery efficiency were synthesized by a simple method. Our study found that the chitosan–ibuprofen aerogels exhibited remarkably improved thermal stability, excellent swelling ratio, and high drug loading. As a consequence of these favorable properties, the chitosan–ibuprofen aerogels exhibited improved drug delivery efficiency and achieved drug prolonged administration. Our study highlights the great potential of polymer–drug aerogels in improving the drug delivery efficiency of transdermal drug delivery systems.