Biological Characterization of Polymeric Matrix and Graphene Oxide Biocomposites Filaments for Biomedical Implant Applications: A Preliminary Report

Carbon nanostructures application, such as graphene (Gr) and graphene oxide (GO), provides suitable efforts for new material acquirement in biomedical areas. By aiming to combine the unique physicochemical properties of GO to Poly L-lactic acid (PLLA), PLLA-GO filaments were produced and characterized by X-ray diffraction (XRD). The in vivo biocompatibility of these nanocomposites was performed by subcutaneous and intramuscular implantation in adult Wistar rats. Evaluation of the implantation inflammatory response (21 days) and mesenchymal stem cells (MSCs) with PLLA-GO took place in culture for 7 days. Through XRD, new crystallographic planes were formed by mixing GO with PLLA (PLLA-GO). Using macroscopic analysis, GO implanted in the subcutaneous region showed particles’ organization, forming a structure similar to a ribbon, without tissue invasion. Histologically, no tissue architecture changes were observed, and PLLA-GO cell adhesion was demonstrated by scanning electron microscopy (SEM). Finally, PLLA-GO nanocomposites showed promising results due to the in vivo biocompatibility test, which demonstrated effective integration and absence of inflammation after 21 days of implantation. These results indicate the future use of PLLA-GO nanocomposites as a new effort for tissue engineering (TE) application, although further analysis is required to evaluate their proliferative capacity and viability.

Characterisation of Rapid In Situ Forming Gelipin Hydrogel for Future Use in Irregular Deep Cutaneous Wound Healing

The irregular deep chronic wound is a grand challenge to be healed due to multiple factors including slow angiogenesis that causing regenerated tissue failure. The narrow gap of deep wounds could hinder and slow down normal wound healing. Thus, the current study aimed to develop a polymerised genipin-crosslinked gelatin (gelipin) hydrogel (GNP_GH) as a potential biodegradable filler for the abovementioned limitations. Briefly, GNP_GH bioscaffolds have been developed successfully within three-minute polymerisation at room temperature (22–24 °C). The physicochemical and biocompatibility of GNP_GH bioscaffolds were respectively evaluated. Amongst GNP_GH groups, the 0.1%GNP_GH10% displayed the highest injectability (97.3 ± 0.6%). Meanwhile, the 0.5%GNP_GH15% degraded within more than two weeks with optimum swelling capacity (108.83 ± 15.7%) and higher mechanical strength (22.6 ± 3.9 kPa) than non-crosslinked gelatin hydrogel 15% (NC_GH15%). Furthermore, 0.1%GNP_GH15% offered higher porosity (˃80%) and lower wettability (48.7 ± 0.3) than NC_GH15%. Surface and cross-section SEM photographs displayed an interconnected porous structure for all GNP_GH groups. The EDX spectra and maps represented no major changes after GNP modification. Moreover, no toxicity effect of GNP_GH against dermal fibroblasts was shown during the biocompatibility test. In conclusion, the abovementioned findings indicated that gelipin has excellent physicochemical properties and acceptable biocompatibility as an acellular rapid treatment for future use in irregular deep cutaneous wounds.

Facile production of chlorophyllides using recombinant CrCLH1 and their cytotoxicity towards multidrug resistant breast cancer cell lines

The purity of chlorophylls plays one of the key role for the production of chlorophyllides. We have designed a facile method for chlorophyll purification by twice solvent extraction. Twice extraction causes the loss of chlorophylls, but the purity of total chlorophylls can be enhanced 182%. Then, the purified chlorophylls can be converted to relatively pure chlorophyllides facilely. The results show that higher purity of chlorophyllides could be obtained when purified chlorophylls (ethanol-hexane extract) was used as starting materials than that of crude chlorophylls (ethanol-only extract). In biocompatibility test, the results showed that the prepared chlorophyllides can be applied as biomaterials. When the prepared chlorophyllides were applied to anticancer tests, they were active both in MCF7 and MDA-MB-231 (multidrug resistant breast cancer cells) cell lines. In addition, the results suggested that the prepared chlorophyllides could be a potential candidate of combination therapy with doxorubicin to breast cancers.

Prevention of urinary infection through the incorporation of silver–ricinoleic acid–polystyrene nanoparticles on the catheter surface

Nosocominal infections associated with biofilm formation on urinary catheters cause serious complications. The aim of this study was to investigate the feasibility of the polyurethane (PU) catheter modified with tetracycline hydrochloride (TCH) attached Ag nanoparticles embedded PolyRicinoleic acid-Polystyrene Nanoparticles (PU-TCH-AgNPs-PRici-PS NPs) and the influence on antimicrobial and antibiofilm activity of urinary catheters infected by Escherichia coli and Staphylococcus aureus. For this purpose, AgNPs embedded PRici graft PS graft copolymers (AgNPs-PRici-g-PS) were synthesized via free radical polymerization and characterized by FTIR, HNMR and DSC. AgNPs-PRici-PS NPs were prepared and optimized by the different parameters and the optimized size of nanoparticle was found as about 150 ± 1 nm. The characterization of the nanoparticles and the morphological evaluation were carried out by FTIR and SEM. Short term stability of nanoparticles was realised at 4°C for 30 days. In vitro release profiles of TCH and Ag NPs were also investigated. The formation of biofilm on PU modified TCH-Ag NPs-PRici-PS NPs, was evaluated and the biocompatibility test of the nanoparticles was realized via the mouse fibroblast (L929) and mouse urinary bladder cells (G/G An1). This is the first time that TCH-AgNPs-PRici-PS NPs used in the modification of PU catheter demonstrated high antimicrobial and antibiofilm activities against the urinary tract infection.

The Development of a Novel Device Based on Loss of Guidewire Resistance to Identify Epidural Space in a Porcine Model

Background. The application of additive manufacturing (3D printing) has been recently expanded to various medical fields. The new technique named loss of guide wire resistance (LOGR) was developed via 3D printing for the detection of epidural space using a guide wire instead of air or saline used in the loss of resistance (LOR) technique. Methods. The prototype model of epidural space finder consists of a polyactic acid (PLA) or a resin. It was manufactured with 3D printing. Biocompatibility test (eluate and sterility tests) was performed in both products. The advantage of the newly developed device was compared with conventional loss of resistance (LOR) technique in a porcine model. Results. Eluate and sterility tests revealed that the PLA was more biocompatible than the resin. The LOGR technique facilitated rapid access to epidural space compared with the LOR technique (41.64 ± 32.18 vs. 92.28 ± 61.46 seconds, N = 14, p=0.0102, paired sample t-test), without any differences in success rate (87.5%). Conclusion. We conclude that LOGR technique is comparable to LOR technique to access the epidural space, although the advantage of either technique in terms of complications such as dural puncture or epidural hematoma is unknown. We demonstrated the potential benefit of 3D printer for the development of a new medical device for anesthesia.

Green Synthesis of Gold and Silver Nanoparticles Using Leaf Extract of Clerodendrum inerme; Characterization, Antimicrobial, and Antioxidant Activities

Due to their versatile applications, gold (Au) and silver (Ag) nanoparticles (NPs) have been synthesized by many approaches, including green processes using plant extracts for reducing metal ions. In this work, we propose to use plant extract with active biomedical components for NPs synthesis, aiming to obtain NPs inheriting the biomedical functions of the plants. By using leaves extract of Clerodendrum inerme (C. inerme) as both a reducing agent and a capping agent, we have synthesized gold (CI-Au) and silver (CI-Ag) NPs covered with biomedically active functional groups from C. inerme. The synthesized NPs were evaluated for different biological activities such as antibacterial and antimycotic against different pathogenic microbes (B. subtilis, S. aureus, Klebsiella, and E. coli) and (A. niger, T. harzianum, and A. flavus), respectively, using agar well diffusion assays. The antimicrobial propensity of NPs further assessed by reactive oxygen species (ROS) glutathione (GSH) and FTIR analysis. Biofilm inhibition activity was also carried out using colorimetric assays. The antioxidant and cytotoxic potential of CI-Au and CI-Ag NPs was determined using DPPH free radical scavenging and MTT assay, respectively. The CI-Au and CI-Ag NPs were demonstrated to have much better antioxidant in terms of %DPPH scavenging (75.85% ± 0.67% and 78.87% ± 0.19%), respectively. They exhibited excellent antibacterial, antimycotic, biofilm inhibition and cytotoxic performance against pathogenic microbes and MCF-7 cells compared to commercial Au and Ag NPs functionalized with dodecanethiol and PVP, respectively. The biocompatibility test further corroborated that CI-Ag and CI-Au NPs are more biocompatible at the concentration level of 1–50 µM. Hence, this work opens a new environmentally-friendly path for synthesizing nanomaterials inherited with enhanced and/or additional biomedical functionalities inherited from their herbal sources.

EVALUATION OF POLYMORPHONUCLEAR IMMUNE CELLS IN BIOCOMPATIBILITY TEST DFLP SPONGE CARTILAGE SCAFFOLD, ADIPOSE DERIVED MSC AND SECRETOME WITH CARTILAGE INJECTION MODEL

Background: In recent years, Freeze-Dried Scaffold Bovine Cartilage has been widely used as an alternative therapy for joint cartilage defects. This study aims to determine the biocompatibility of scaffold without involving implantation which provides clinical reports as expected through the evaluation of post-implantation chondrocytes regeneration, biocompatibility markers of the scaffold, and biocompatibility of sponge cartilage scaffold involving cartilage defects New Zealand White Rabbit.Methods: This experimental in-vivo study was conducted for four weeks. Rabbits were divided into 4 treatment groups: microfracture defect group with DFLP sponge cartilage scaffold (P1) implantation; Microfracture defect group with DFLP sponge cartilage scaffold-secretome implantation (P2); Microfracture defect group with DFLP sponge cartilage scaffold-adipose derived Mesenchymal Stem Cells (ADMSCs) (P3); Microfracture defect group without implantation (control). The evaluations of basophil, eosinophil, neutrophil, and polymorphonuclear (PMN) cells were done in the first 24 hours, 3 days, and 1 week after the treatment. The collected data will be analyzed statistically.Results: Research observations performed three times in the first, third, and seventh days. The results showed a small number of average Neutrophil (Neutrophil granulated) and PMN (segmented Neutrophils) cells both in the P2 and P3 groups compared with the control and the P1 group.Conclusion: In general, biocompatibility is not included on the cytotoxic effects including inflammatory reactions and post-cartilage scaffold sponge implantation (DFLP) with or without the addition of ADMSC and secretome in the white rabbit New Zealand cartilage defect associated with differences seen in eosinophils, basophils, neutrophils, also total PMN cells in four groups.

Eu3 + doped hydroxyapatite as a fluorescent material for biomedical applications

The present study is based on obtaining a contrast agent but improved with a mineralogical phase for hard tissue medical imaging. In this sense, Eu3 + is used for the contrast agent part, because of the luminescent properties and for the action part on bone regeneration the hydroxyapatite is used. The obtained mix focuses on the promotion of information regarding the development of new bone tissue, which is evidenced by the luminescent Eu3 +. Using a simple method of synthesis, it was obtained a luminescent europium-doped nanohydroxyapatite which was characterized by physico-chemical and biological point of view. With the SEM, TEM and XRD equipment’s the morphological and structural properties were analyzed. Also, to evaluate the luminescent features of the obtained material it was subjected to the UV-Vis and photoluminescence (PL) spectra. Because of the fact that the material has application in medical investigation and not only, it was performed a biocompatibility test (MTT assay) and fluorescent microscopy. The results can be a promising start due to its characteristics, in such manner the Eu3 + doped hydroxyapatite can be used as a fluorescent material for biomedical applications [1].