Smart chitosan nanogel for targeted doxorubicin delivery, ensuring precise release, and minimizing side effects in Ehrlich ascites carcinoma-bearing mice

In recent decades, bio-polymeric nanogels have become a forefront in medical research as innovative in-vivo drug carriers. This study introduces a pH-sensitive chitosan nanoparticles/P(N-Isopropylacrylamide-co-Acrylic acid) nanogel (CSNPs/P(NIPAm-co-AAc)), making significant advancements. The nanogel effectively encapsulated doxorubicin hydrochloride (Dx. HCl), a model drug, within its compartments through electrostatic binding. Comparing nano chitosan (CSNPs) before and after integrating copolymerized P(NIPAm-co-AAc), highlighting an improved and adaptable nanogel structure with responsive behaviors. The intraperitoneal delivery of Dx-loaded nanogel (Dx@N.gel) to Ehrlich ascites carcinoma (Eh)-bearing mice at doses equivalent to 1.5 and 3 mg/kg of Dx per day for 14 days exhibited superiority over the administration of free Dx. Dx@N.gel demonstrated heightened anticancer activity, significantly improving mean survival rates in Eh mice. The nanogel's multifaceted defense mechanism mitigated oxidative stress, inhibited lipid peroxidation, and curbed nitric oxide formation induced by free Dx. It effectively countered hepatic DNA deterioration, normalized elevated liver and cardiac enzyme levels, and ameliorated renal complications. This pH-responsive CSNPs/P(NIPAm-co-AAc) nanogel loaded with Dx represents a paradigm shift in antitumor drug delivery. Its efficacy and ability to minimize side effects, contrasting sharply with those of free Dx, offer a promising future where potent cancer therapies seamlessly align with patient well-being.

Synthesis, characterization of poly L(+) lactic acid and its application in sustained release of isosorbide dinitrate

Poly L(+) lactic acid (PLLA) has become crucial in the biomedical industry for various uses. The direct polycondensation method was used to prepare Poly L(+) Lactic Acid (PLLA). Different catalysts, including metal oxides and metal halides, were used to test the polymerization technique. The effect of the amount of catalysts and the type of coupling agent were investigated. The effect of reaction time and polymerization solvents was also studied. PLLA was loaded with isosorbide dinitrate utilizing the solvent evaporation process. The synthesized polymer-drug system was evaluated by different means such as FT-IR, TGA, DSC, XRD, entrapment efficiency (E.E), drug loading (D.L), particle size analysis, and zeta potential determination. Studies on in-vitro release using UV light at 227 nm at various pH levels were conducted, and the kinetics of release and cytotoxicity using the sulforhodamine B (SRB) assay on human skin fibroblast cells were examined.

Synthesis of Cross-Linked and Sterilized Water-Soluble Electrospun Nanofiber Biomatrix of Streptomycin-Imbedded PVA/CHN/β-CD for Wound Healing

The diagnosis and prognosis of chronic wounds are demanding and require objective assessment. Because of their potential medicinal applications, the syntheses of biopolymeric chitosan (CHN) structure and PVA-based mixed electrospun nanofibers with biomimetic features were thoroughly investigated. This study created different formulas, including a guest molecule and capping agent, using supporting PVA as a vehicle. CHN was used as a biomodifier, and beta-cyclodextrin (ß-CD) as a smoother and more efficiently entraps streptomycin (STP) compared with the silver sheet wound dressing. The relevant analyses showed that the size distribution increased with the incorporation of PVA, CHN, and ß-CD to 120.3, 161.9, and 192.02 nm. The webs boosted particle size and released content stability to 96.4% without compromising the nanofiber structure. Examining the synergistic effects of the PVA/CHN/STP/ß-CD nanoformulation against pathogenic strains of S. aureus, P. aeruginosa, and Aspergillus niger, clean zones were 47 ± 3.4, 45 ± 3.0, and 49 ± 3.7 mm were produced. PVA/CHN/STP/ß-CD formula exhibited a 98.9 ± 0.6% cell viability and wound closure of 100% at 72 h. The results reveal that the PVA/CHN/STP/ß-CD formula is promising for medical applications, especially in wound healing, compared with the silver sheet.

Intriguing and Facile Preparation Approach of CdO Nanorod-Based Abundant Chitosan for Symmetric Supercapacitors

Abundant chitosan was rationally used for the green fabrication of cadmium oxide nanorods (CdO nanorods) owing to its environmentally benign characteristics, bioavailability, low cost, etc. However, the primary unsubstituted amino group of chitosan interacts with the surface of Cd salt at higher temperatures, resulting in CdO nanorod formation. A one-step hydrothermal technique was adopted in the presence of chitosan. Optical, structural, and morphology techniques characterized CdO nanorods. According to X-ray diffraction crystallography, CdO is well crystallized in the face-centered cubic lattice with an Fm-3m (225) space group. The AC@CdO nanoelectrode demonstrated an outstanding gravimetric capacitance of 320 F g-1 at a current density of 0.5 A g-1, nearly three-fold that of ordinary AC electrodes. The AC electrode and the AC@CdO nanoelectrode retain 90 and 93% of their initial specific capacitance after 10,000 galvanostatic charge discharge cycles. The AC@CdO nanoelectrode has a lower equivalent series resistance value than the AC electrode. Moreover, AC@CdO symmetric supercapacitor devices achieve excellent results in terms of specific energy, specific power, and capacitance retention.

Enhance the oral insulin delivery route using a modified chitosan-based formulation fabricated by microwave

Chitosan (Cs) was subjected to ball milling and subsequently functionalized with Dinitro salicylic acid (Cs-DNS) to enhance the efficacy of oral insulin delivery. The hydrodynamic spherical particle sizes exhibited 33.29 ± 5.08 nm for modified Cs-DNS NPs. Irrespective of insulin entrapment, zeta potential measurements revealed positively charged Cs-DNS NPs (+ 35 ± 3.5 mV). The entrapment performance (EP%) was evaluated in vitro, and insulin release patterns at various pH levels. The EP% for Cs-DNS NPs was 99.3 ± 1.6. Cs- DNS NPs retained a considerable amount of insulin (92 %) in an acidic medium, and significant quantities were released at increasing pH values over time. In vivo investigations, the diabetic rats which taken insulin-incorporated NPs had lower serum glucose levels (SGL) after 3 h to (39.4 ± 0.6 %) for Cs- DNS NPs. For insulin-incorporated Cs- DNS NPs, the bioavailability (BA%) and pharmacological availability (PA%) were 17.5 ± 0.31 % and 8.6 ± 0.8 %, respectively. The assertion above highlights the significance and effectiveness of modified chitosan in promoting insulin delivery, decreasing SGL levels, and guaranteeing safety.

Controlled synthesis of in-situ gold nanoparticles onto chitosan functionalized PLGA nanoparticles for oral insulin delivery

Chitosan-based nanoparticles (chitosan nanoparticles (ChNps), chitosan gold Nps (ChAuNps), and chitosan gold Nps functionalized with poly lactic-co-glycolic acid (PLGA) (ChAuNps/PLGA)) were prepared as nanocarriers for insulin to improve its oral uptake. The emulsion solvent diffusion method was employed to functionalize the Nps with PLGA. TEM, SEM, DLS, and zeta potential were conducted to characterize the Nps. The morphological analysis confirmed the formation of spherical Nps with hydrodynamic particle sizes of 138±23, 16±2.2, and 50±9.3 nm for ChNps, ChAuNps, and ChAuNps/PLGA, respectively. Zeta potential measurements indicated two types of Nps, regardless of insulin entrapment, positively charged, (ChNps (+36 ± 4.2, +31 ± 2.2mv)) and ChAuNps (+37 ± 4.3, +33 ± 2.5mv) and negatively charged (ChAuNps/PLGA (-31 ± 2.7, -26 ± 2.1 mv)). The in vitro studies were assessed by measuring the entrapment efficiencies (EE%) and the release profiles of insulin at different pH values. EE% for ChNps, ChAuNps, and ChAuNps/PLGA were 97 ± 1.5, 98.4 ± 1.9, and 99 ± 1.2%, respectively. At an acidic medium, a significant level of insulin retention was observed (96 ± 0.08%) for ChAuNps/PLGA. While a high amount was released at higher pH values over an extended period of time. In vivo studies, diabetic rats treated with insulin-loaded Nps had reduced blood glucose level (BGL) (38 ± 2.8, 35 ± 6.5, and 27 ± 5.6%) for ChNps ChAuNps and ChAuNps/PLGA, respectively. The pharmacological availability (PA%) and bioavailability (FR%) for insulin-loaded ChAuNps/PLGA were 15.8 ± 0.71% and 7.7 ± 0.93%, respectively. Altogether, emphasize the role of biocompatible Nps and their efficiency in the convenient delivery of insulin, thus lowering the BGL in a safe condition.

Three waves changes, new variant strains, and vaccination effect against COVID-19 pandemic

It has been more than one year since the first case of the coronaviruses was infected by COVID-19 in China. The world witnessed three waves of the corona virus till now, and more upcoming is expected, whereas several challenges are presented. Empirical data displayed that the features of the virus effects do vary between the three periods. The severity of the disease, differences in symptoms, attitudes of the people have been reported, although the comparative characteristics of the three waves still keep essentially indefinite. In contrast, the sense of danger toward the cries gradually decreases in most countries. This may be due to some factors, including the approved vaccines, introducing alternative plans from politicians to control and deal with the epidemic, and decreasing the mortality rates. However, the alarm voice started to rise again with the appearance of new variant strains with several mutations in the virus. Several more questions began to be asked without sufficient answers. Mutations in COVID-19 have introduced an extreme challenge in preventing and treating SARS-COV-2. The essential feature for mutations is producing new variants known by high tensmibility, disturbing the viral fitness, and enhancing the virus replication. One of the variants that has emerged recently is the Delta variant (B.1.617.2), which was firstly detected in India. In November 2021, a more ferocious mutant appeared in South Africa, also called omicron (B.1.1.529). These mutants grabbed world attention because of their higher transmissibility than the progenitor variants and spread rapidly. Several information about the virus are still confusing and remains secret. There are eight approved vaccines in the market; however, the investigation race about their effect against reinfection and their role against the new variants is still under investigation. Furthermore, this is the first time vaccinating against COVID-19, so the question remains: Will we need an annual dose of the corona vaccines, and the side effects don't been observed till now?

Spectroscopic study of self-assembly of anti-hepatitis C virus sofosbuvir drug with bio-polymeric nanoparticles for improving the drug release effect

Self-assembly of Sofosbuvir drug (SOF) anti-hepatitis C virus (HCV) with bio-polymeric nanoparticles such as chitosan nanoparticles (Cs NPs) and polyvinyl alcohol nanoparticles (PVA NPs), the novel composites have been characterized successfully by different analysis such as Energy-dispersive X-ray spectroscopy (EDX), Scanning electron microscopy (SEM), UV-Visible spectrophotometer (UV-Vis) and Fourier Transmittance Infrared (FT-IR). The improvement of the Sofosbuvir effect as a result of loading drug on the bio-polymer NPs surface has been detected by the UV-Vis, and fluorescence spectroscopy techniques. The improvement of SOF efficiency was revealed via studying the drug release of SOF from biopolymers NPs surface at pH 7.4, UV-Vis spectra used for the releasing process. The binding constant (K_b) value was reported at 0.000055 and 0.3613 min^-1 for Cs and PVA NPs respectively. Also, the value of K_SV was documented at 0.0014 and 7.16 min^-1 for Cs@SOF and PVA@SOF hybrid nanocomposite. The incorporation rate (k) of SOF on the surface of biopolymer nano molecules was calculated to be 0.00812 and 0.0165 min^-1 for Cs and PVA NPs, respectively. Besides the observed value of (n) was close to the unit 0.74 and 0.86 for Cs and PVA NPs, respectively. The SOF released from Cs NPs surface was documented at 0.09 mg after 24 h, while PVA NPs reported at 0.7 mg at the same time and the release efficiency is 56.5 and 73% for Cs@SOF and PVP@SOF, respectively. From the results, we suggest Cs/SOF and PVA/SOF hybrid nanocomposites have spectroscopic results that make them promising candidate drugs, but need to the clinical trials.

New Prospects in Nano Phased Co-substituted Hydroxyapatite Enrolled in Polymeric Nanofiber Mats for Bone Tissue Engineering Applications

The most common forms of tissue impairment are fracture bones and significant bone disorders caused by multiple traumas or normal aging. Surgical care sometimes necessitates the placement of a temporary or permanent prosthesis, which continues to be a challenge for orthopedic surgeons, including those with large bone defects. Electrospun scaffolds made from natural and synthetic nanofiber-based polymers are studied as natural extracellular matrix (ECM)-like scaffolds for tissue engineering. Besides, nanostructured materials have properties and functions depending on the scale of natural materials such as hydroxyapatite (HAP), ranging from 1 to 100 nm, which activity was proficient upon enrolled in nanofiber mats. The use of nanofibers in combination with nano-HAP has increased the scaffold's ability to replicate the construction of natural bone tissue that is the aim of the present text. In bone engineering, nanofiber substrates facilitate cell adhesion, proliferation, and differentiation, while HAP induces cells to secrete ECM for bone mineralization and development. This review aims to draw the reader's attention to the critical issues with synthetic and natural polymers containing HAP in bone tissue engineering; co-substituted hydroxyapatite has also been mentioned.

Chitosan based-nanoparticles and nanocapsules: Overview, physicochemical features, applications of a nanofibrous scaffold, and bioprinting

Recent advancements in the synthesis, properties, and applications of chitosan as the second after cellulose available biopolymer in nature were discussed in this review. A general overview of processing and production procedures from A to Z was highlighted. Chitosan exists in three polymorphic forms which differ in degree of crystallinity (α, β, and γ). Thus, the degree of deacetylation, crystallinity, surface area, and molecular mass significantly affect most applications. Otherwise, the synthesis of chitosan nanofibers is suffering from many drawbacks that were recently treated by co-electrospun with other polymers such as polyvinyl alcohol (PVA), polyethylene oxide (PEO), and polycaprolactone (PCL). Ultimately, this review focuses on the area of new trend utilization of chitosan nanoparticles as nanospheres and nanocapsules, in cartilage and bone regenerative medicine. Owing to its biocompatibility, bioavailability, biodegradability, and costless synthesis, chitosan is a promising biopolymeric structure for water remediation, drug delivery, antimicrobials, and tissue engineering.

The degradation of methylene blue dye using copper-doped hydroxyapatite encapsulated into polycaprolactone nanofibrous membranes

Methylene blue is degraded under visible light irradiation in the presence of the nanofibrous membranes of PCL containing modified HAP with different contents of Cu ions.

Polycaprolactone based electrospun matrices loaded with Ag/hydroxyapatite as wound dressings: Morphology, cell adhesion, and antibacterial activity

The development of a scaffold matrix that can inhibit bacterial infection and promote wound healing simultaneously is an essential demand to improve the health care system. Hydroxyapatite (HAP) doped with different concentrations of silver ions (Ag⁺) were incorporated into electrospun nanofibrous scaffolds of polycaprolactone (PCL) using the electrospinning technique. The formed phase was identified using XRD, while the morphological and roughness behavior were investigated using FESEM. It was shown that scaffolds were configured in randomly distributed nanofibers with diameters around of 0.19-0.40, 0.31-0.54, 1.36, 0.122-0.429 μm for 0.0Ag-HAP@PCL, 0.2Ag-HAP@PCL, 0.6Ag-HAP@PCL, and 0.8Ag-HAP@PCL, respectively. Moreover, the maximum roughness peak height increased significantly from 179 to 284 nm, with the lowest and highest contributions of Ag. The mechanical properties were examined and displayed that the tensile strength increased from 3.11 ± 0.21 MPa to its highest value at 3.57 ± 0.31 MPa for 0.4Ag-HAP@PCL. On the other hand, the cell viability also was enhanced with the addition of Ag and improved from 97.1 ± 4.6% to be around 102.3 ± 3.1% at the highest contribution of Ag. The antibacterial activity was determined, and the highest imbibition zones were achieved at the highest Ag dopant to be 12.5 ± 1.1 mm and 11.4 ± 1.5 mm against E. coli and S. aureus. The in vitro cell proliferation was observed through human fibroblasts cell lone (HFB4) and illustrated that cells were able to grow and spread not only on the fibers' surface but also, they were spreading and adhered through the deep pores.

Synthesis of Biocompatible and Environmentally Nanofibrous Mats Loaded with Moxifloxacin as a Model Drug for Biomedical Applications

Biopolymeric chitosan structure (Cs) is rationally investigated owing to its potentiality in pharmaceutical applications. The synthetic routes of biomimetic Cs-based blend electrospun nanofibers were studied. Herein, biocompatible crosslinked electrospun polyvinyl alcohol (PVA)/Cs-reduced gold nanoparticles (Cs(Rg))/β-CD (beta-cyclodextrin) in pure water were fabricated. To this end, supportive PVA as a carrier, Cs bio modifier, and gold reductant and β-CD as smoother, inclusion guest molecule, and capping agent exhibit efficient entrapment of moxifloxacin (Mox) and consequently accelerate release. Besides, PVA/Cs(Rg)/β-CD paves towards controlled drug encapsulation-release affinity, antimicrobial, and for wound dressing. Without losing the nanofiber structure, the webs prolonged stability for particle size and release content up to 96.4%. The synergistic effect of the nanoformulation PVA/Cs(Rg)/β-CD against pathogenic bacteria, fungus, and yeast, including Staphylococcus aureus, Escherichia coli, Candida albicans, and Aspergillus niger, posed clear zones up to 53 φmm. Furthermore, a certain combination of PVA/Cs (Rg)/β-CD showed a total antioxidant capacity of 311.10 ± 2.86 mg AAE/g sample. In vitro cytotoxicity assay of HePG2 and MCF-7 NF6 can eradicate 34.8 and 29.3 µg/mL against selected cells.

Eco-friendly synthesis of functionalized chitosan-based nanoantibiotic system for potential delivery of linezolid as antimicrobial agents

To obtain a healthy human being with beneficial microflora against different pathogenic infections, classical antibiotics with nanosized biomaterials were used to inhibit the growth of bacterium by their potent synergistic effect. Hence, this study planned to load an oxazolidinone antibiotic named linezolid (LD) onto functionalized chitosan (CN) with 3, 5- dinitrosalyslic acid (DA) via microwave synthesis without harsh condition. The exploring synergistic effect of linezolid (LD) with CN/DA controllable nanostructure was compact efflux-mediated methicillin-resistant Staphylococcus aureus (MRSA) burden and other selected bactericide Gram-positive ((S. aureus), Gram-negative (E. coli), Fungi (C. albicans), Yeast (A. niger), and E. faecalis. The obtained results showed that LD was incorporated into both the internal and external surface of the aggregated CN/DA nanosystem with an average diameter of 150 nm ± 4 hints of the drug loading. Owing to the nature of functionalized CN, the release efficiency attains 98.4% within 100 min. The designed LD@CN/DA exhibited inhibition zone 54 mm, 59 mm, 69 mm, 54 mm, 57 mm, and 24 mm against the tested microbes respectively rather than individual LD. The major target of the current research is achieved by using LD@CN/DA as a nanoantibiotic system that has exceptional consistently active against multi-resistant pathogens, in between MRSA which resist LD. Also, cell viability was performed even after three days of direct cell culture on the surface of the designed nanoantibiotic. The mechanism of microbial inhibition was correlated and rationalized to different charges and the presence of oxygen species against microbial infections. Our findings provide a deep explanation about nanostructured antibiotics design with enhanced potentially pathogen-specific activity.

Halogen bond triggered aggregation induced emission in an iodinated cyanine dye for ultra sensitive detection of Ag nanoparticles in tap water and agricultural wastewater

Aggregation induced emission (AIE) has emerged as a powerful method for sensing applications. Based on AIE triggered by halogen bond (XB) formation, an ultrasensitive and selective sensor for picomolar detection of Ag nanoparticles (Ag NPs) is reported. The dye (CyI) has an iodine atom in its skeleton which functions as a halogen bond acceptor, and aggregates on the Ag NP plasmonic surfaces as a halogen bond donor or forms halogen bonds with the vacant π orbitals of silver ions (Ag⁺). Formation of XB leads to fluorescence enhancement, which forms the basis of the Ag NPs or Ag⁺ sensor. The sensor response is linearly dependent on the Ag NP concentration over the range 1.0–8.2 pM with an LOD of 6.21 pM (σ = 3), while for Ag⁺ it was linear over the 1.0–10 μM range (LOD = 2.36 μM). The sensor shows a remarkable sensitivity for Ag NPs (pM), compared to that for Ag⁺ (μM). The sensor did not show any interference from different metal ions with 10-fold higher concentrations. This result indicates that the proposed sensor is inexpensive, simple, sensitive, and selective for the detection of Ag NPs in both tap and wastewater samples.

Based on AIE triggered by halogen bond (XB) formation, we established an ultrasensitive and selective sensor for picomolar detection of Ag nanoparticles (Ag NPs).

Synthesis of monodisperse core shell PVA@P(AMPS-co-NIPAm) nanogels structured for pre-concentration of Fe(III) ions

Core shell-structured poly(vinyl alcohol) @ poly(2-acrylamido-2-methyl-1-propane-sulfonic acid-co-N-isopropylacrylamide) PVA@P(AMPS-co-NIPAm) spheres are synthesized. The well-defined PVA@P(AMPS-co-NIPAm) core shell nanogels with diameter nearly 30 nm enriches Fe(III), and the nanogels are characterized by FT-IR, TEM, SEM and X-ray diffraction (XRD). The many factors affecting adsorption were successfully investigated. The maximum capacity of Fe(III) ions was 320 (mg/g) for PVA@P(90AMPS-co-10NIPAm) (wt.: wt%). The equilibrium data matching well with the Langmuir model and the pseudo-second-order form described the adsorption process better than the pseudo-first-order model. Findings of the present study highlight using a simple synthesis of PVA@P(AMPS-co-NIPAm) nanogels as superior and recyclable nanoadsorbents.