The present study describes the development of multifunctional hemostatic sponges to control bleeding. Chitosan (Ch) and poly(vinyl alcohol) (PVA) were selected as the basic polymeric matrix [Ch/PVA] for sponges. Glycerol and citric acid were used as crosslinkers [Ch/PVA/G(Cl)] to enhance the mechanical properties of the developed sponges. Ciprofloxacin (AB) was added to the developed sponge to impart antibacterial activity. Hydroxyapatite (HA) was also added, which would make the sponge suitable for bone surgery. Among the developed sponges, the Ch/PVA/G(Cl)-HA-AB sponge demonstrated enhanced cell viability, mechanical properties, and strong antimicrobial effect against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus, in addition to platelet aggregation activity. The addition of ciprofloxacin and hydroxyapatite promotes a unique synergistic effect of antimicrobial activity and hemostasis. Thus, the present study introduces Ch/PVA/G(Cl)-HA-AB, a multifunctional hemostatic sponge that would be suitable for bone surgical applications.

To examine the utilization of metal oxide nanoparticles (NPs) in different commercial products, this work focuses on the determination of cost-effective and scalable synthesis protocols. The solvothermal protocol is well-known as a scalable method but has recently been shown to lack economic feasibility. The mechanochemical method has recently been recognized to be a more economic and environmentally friendly substitute for the solvothermal method. In this study, zinc oxide nanoparticles (ZnO NPs) and copper oxide nanoparticles (CuO NPs) were synthesized using two (aqueous and organic) solvothermal (wet) methods and two (manual and automated) mechanochemical (dry) methods. The four methods were evaluated and compared. The automated mechanochemical method generated a significantly higher yield of ZnO NPs (82%) and CuO NPs (84%) using the least energy and time. However, the prepared ZnO NPs displayed higher cytotoxicity against Vero E6 cells when compared to that of CuO NPs. Because of their low cytotoxicity, CuO NPs synthesized via the automated mechanochemical method were selected for application onto cotton fabrics. Lower cytotoxicity was observed for CuO NPs treated fabrics with an IC50 of 562 mg/mL and ZnO treated fabrics with an IC50 at 23.93 mg/mL when the treated fabrics were tested against L929 fibroblast cells. Additionally, the cotton fabrics retained bactericidal and virucidal effects after four washes. Thus, the current study recommends the automated mechanochemical method as a cost-effective scalable approach for the synthesis of CuO NPs. The application of CuO NPs onto cotton fabrics generated washable antimicrobial face masks.

Cellulose is a widely available and renewable biopolymer that can be extracted from different natural sources such as plants, and bacteria. Rice husk is of special interest as a source of cellulose, as it is abundant and has a high cellulose content. The extraction of cellulose from rice husk has traditionally been a multi-step procedure that is time-consuming and involves the use of harsh chemicals. However, in this study, a one-step facile method was developed and optimized for the extraction of cellulose from rice husks. The process involved adjusting the ratio of sodium hypochlorite solution to the mass of solid rice husk and the progressive removal of non-cellulosic constituents was confirmed via scanning electron microscopy (SEM), and Maule lignin test. The extracted cellulose was then incorporated into glass ionomer cement (GIC) for dental applications. The mechanical properties of the GIC have increased in G12 and G18 vs. an observable decrease in G21 (p = 0.02 and p = 0.01, respectively), including increased compressive strength and stiffness. The addition of 3% cellulose extracted using C12 conditions (1 husk : 12 hypochlorite for 6 h) to GIC has increased GIC mechanical strength by 130% as compared to control GIC. The addition of 1% cellulose extracted using C18 conditions (1 husk : 18 hypochlorite for 6 h) to GIC has increased GIC mechanical strength by 58.5% as compared to the control. In conclusion, cellulose can be extracted from rice husks using a one-step facile method, and its incorporation into GIC can enhance its mechanical properties and improve its potential use for dental applications.

Over the past several decades, the development of engineered small particles as targeted and drug delivery systems (TDDS) has received great attention thanks to the possibility to overcome the limitations of classical cancer chemotherapy, including targeting incapability, nonspecific action and, consequently, systemic toxicity. Thus, this research aims at using a novel design of Poly(N-isopropylacrylamide) p(NIPAM)-based microgels to specifically target cancer cells and avoid the healthy ones, which is expected to decrease or eliminate the side effects of chemotherapeutic drugs. Smart NIPAM-based microgels were functionalized with acrylic acid and coupled to folic acid (FA), targeting the folate receptors overexpressed by cancer cells and to the chemotherapeutic drug doxorubicin (Dox). The successful conjugation of FA and Dox was demonstrated by dynamic light scattering (DLS), Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), UV-VIS analysis, and differential scanning calorimetry (DSC). Furthermore, viability assay performed on cancer and healthy breast cells, suggested the microgels’ biocompatibility and the cytotoxic effect of the conjugated drug. On the other hand, the specific tumor targeting of synthetized microgels was demonstrated by a co-cultured (healthy and cancer cells) assay monitored using confocal microscopy and flow cytometry. Results suggest successful targeting of cancer cells and drug release. These data support the use of pNIPAM-based microgels as good candidates as TDDS.

General anaesthetics are routinely used to sedate patients during prolonged surgeries and administered via intravenous injection and/or inhalation. All anaesthetics have short half-lives, hence the need for their continuous administration. This causes several side effects such as pain, vomiting, nausea, bradycardia, and on rare occasions death post-administration. Several clinical trials studied the synergetic effect of a combination of anaesthetic drugs to reduce the drug load. Another solution is to encapsulate anaesthetics in nanoparticles to reduce their dose and side effects as well as achieve their sustained release manner. Different types of nanoparticles were developed as carriers of intravenous and intrathecal anaesthetics generating platforms which facilitate drug transport across the blood–brain barrier (BBB). Nanocarriers encapsulating common anaesthetic drugs such as propofol, etomidate, and ketamine were developed and characterized in terms of size, stability, onset and duration of loss of right reflex, and tolerance to pain in small animal models. The review discusses the types of nanocarriers used to reduce the side effects of the anaesthetic drugs while prolonging the sedation time. More rigorous studies are still required to evaluate the nanocarrier formulations regarding their ability to deliver anaesthetic drugs across the BBB, safety, and finally applicability in clinical settings.