Journal of Bioactive and Compatible Polymers

The bleeding problem might seem straightforward, but it involves a plethora of complex biochemical pathways and responses. Hemorrhage control remains one of the leading causes of “preventable deaths” worldwide. The past few decades have seen a wide range of biomaterials and their derivatives targeted to serve as hemostatic agents, but none can be deemed as an ideal solution. In this review, we have highlighted the current diversity in hemostatic agents and their modalities. We have enclosed a comprehensive outlook of the proposed solutions and their clinical performance so far. In addition to these, several promising compositions are still in their infancy or developmental phases. The inclusion of novel upcoming nanocomposites has further widened the potencies of existing formulations as well.

A method for purifying the polysaccharides from Sterculia foetida L. gum was developed. The effects of purifying conditions were also studied. Results have shown that the conditions of pH 0.5, temperature of 80°C, and 2.5-h reaction duration gave the best polysaccharides yield. The mineral content and the molecular weight of the obtained polysaccharides were measured for characterization. The cross-linking of the polysaccharides with citric acid in order to achieve a desired polymer was performed successfully. The obtained polymers under different conditions were evaluated for the potential application as a hemostatic agent, including tests of swelling behavior in different fluids, whole-blood clotting time and enzymatic bio-degradation. Results have shown that the citric acid/polysaccharides ratio of 0.01 produced a comparative yield of polymer flakes with increased swelling properties, as well as shortened in vitro blood clotting time and gradual biodegradability in three experimental days. Therefore, the citric acid/polysaccharides ratio of 0.01 was selected for the subsequent experiment to obtain the polymer after 1.5 h of purification, which gave the best swelling properties, 20 times the initial weight, reduced the whole-blood clotting time by 50% and showed a rapid bio-degradation. The results obtained from this study provide essential knowledge on the research of the use of S. foetida gum polysaccharides as a passive hemostatic agent, thereby extending the potential pharmaceutical applications of natural polysaccharides in Vietnam.

As a biosynthetic polymer, Bacterial cellulose (BC) has been largely used in biomedical and technological fields for the excellent biocompatibility and water holding capability. In this study, BC hydrogel were mass-produced from G. xylinus. A novel gel, BC nanocomposite (BC/NC) hydrogel, was prepared via in situ free radical aqueous polymerization from NIPAM in the presence of Clay was added as physical crosslinker. The physical and chemical properties were evaluated, and the results showed that the properties of the composite hydrogel were improved, for example, the Young’s modulus rose by nearly 30%, from 4.7 to 6.0 Mpa with the increasing of NIPAM. BC/NC-lys hydrogel were prepared by treating BC/NC hydrogel with Lysostaphin solution, and the cytocompatibility and antibacterial activities were assessed in vitro. The effects of composite hydrogel on wound healing were examined in rat skin models, the cure rate was up to 92.35% in the test group and only 78.83% in the control group after 14 days. The composite BC/NC3-lys hydrogel were developed in the hope of accelerating the wound healing process as well as decreasing the infection rate.

Fabricating degradable polymer-based membranes has attracted much attention for guided bone regeneration. Chitosan/gelatin (Cs/Gel) composites are among the most known scaffolds with structural similarity to bone matrix and a high potential to support cell attachment and proliferation. Recently, plant-derived phenolic compound apigenin has been identified to direct the osteogenic differentiation of mesenchymal stem cells and retain osteoblast metabolic functions. We incorporated apigenin into Cs/Gel membranes to improve apigenin bioavailability and get proper concentrations for efficient biological activities. Apigenin-loaded Cs/Gel membranes were prepared using a solution casting method with various apigenin contents (0, 10, 25, 50, and 100 µM). Chemical composition, morphological characteristics, swelling behavior, degradation rate, and apigenin release from membranes were evaluated. Saos-2 osteoblasts were cultured on membranes to investigate cell-membrane interaction, proliferation, viability, and mineralization under the osteogenic culture condition. The results showed that membranes had homogeneous and moderate rough surfaces, facilitating osteoblast attachment and expansion. Swelling ratios exceeded 200%, reaching a stable rate in 24 h. Apigenin-loaded membranes degraded slower in vitro. Membranes containing lower apigenin concentrations exhibited a higher cargo release profile over 21 days. Apigenin improved osteoblast proliferation and viability, but the mineralization depended on apigenin dose, with optimized values at low concentrations. These data suggested that Cs/Gel membranes loaded with low apigenin contents improved osteoblast survival, proliferation, and mineralization.

A leading cancer diagnosis in women worldwide is cervical cancer, with current treatments all posing a risk of serious side effects. Less toxic, but effective treatments are sought after. Aloe vera (barbadensis miller), known for its beneficial properties, has been studied for cancer treatment. While aloe gel has been shown to exhibit anti-cancer activity, it cannot form a hydrogel alone. Therefore, an interpenetrating network comprising alginate blended with aloe was examined as a cervical cancer treatment. We hypothesized the antioxidant properties of aloe gel would decrease cancer cell viability while the alginate hydrogel would improve mucoadhesion. We further hypothesized the antioxidant activity of aloe gel would induce cancer cell death at levels similar to common chemotherapeutics, and aimed to determine if these chemotherapeutic behaviors are constructive or destructive. Material and adhesive properties, drug encapsulation, and cancer cell viability were investigated and validated. The effect of aloe-alginate hydrogels on cervical cancer cell viability was not significantly different compared to aloe-blends containing doxorubicin (DOX), indicating that the aloe alone decreased cancer cell viability rendering the additional cytotoxic therapeutic not impactful as an adjuvant therapy. This study provides insight into the potential of natural biopolymers for treating cervical cancer without systemic toxic compounds.

This study evaluates the use of chitosan–silver nanocomposites (CSN) as an insecticide against the bed bug (Cimex lectularius). Adult bed bugs were collected from infested residential areas and identified using light microscopy and scanning electron microscopy. CSN were prepared and photographed for characterization using transmission electron microscopy, dynamic light scattering, and zeta potential. The insecticidal effect of different concentrations of CSN (400–1000 ppm) was compared to that of 0.1% cypermethrin as a positive control and normal saline as a negative control. The bugs (n = 25) were immersed for 20 min in the corresponding medium, dried with filter papers, and then incubated at 27–28°C and 70% RH with a 12:12 h light–dark photoperiod. The mortality rates were recorded at different time intervals (2, 4, 6, 12, and 24 h post-incubation (hPI)), and the entire experiment was repeated five times. Image analysis showed round- to spherical-shaped CSN ranging in size from 34 to 72 nm. The mortality rates were positively associated with increasing concentrations of CSN. The mortality rate first reached 100% for concentrations of 800 ppm at 24 hPI and 1000 ppm at 12 hPI. The calculated LC₅₀ was found at a concentration of 1165 ppm at 2 hPI, and the LC₉₉ was found at a concentration of 1914 ppm at 2 hPI. The positive control, cypermethrin, induced 100% mortality among the bugs at 2 hPI, while the negative control caused no mortality. These results clearly show the potential of CSN as an insecticide against C. lectularius. Future studies on best practices for implementing these particles in clinical settings are recommended.