Polymer based hydrogel

Abstract

The present invention relates to an anti-aging antimicrobial wound healing polymer based hydrogel. In the study of the present invention, a wound healing gel formulation is developed by combining poloxamer polymers and boron component at adequate concentrations in a carbopol based gel. The said gel exhibits fast action on the damaged area and prevents scar formation.

Claims

1. An anti-aging, wound-healing and antimicrobial hydrogel, which is comprising: 3% boron compound, 4% poloxamer and 1% gel; wherein the boron compound and the poloxamer are added to the gel that is prepared as a carrier, wherein the boron compound is selected from a group consisting of sodium pentaborate pentahydrate, boric acid, alkaline and alkaline earth metal borates and all hydrate forms of these borates, ammonium borates, and boric acid esters.

2. The hydrogel according to claim 1, wherein the gel comprises carbopol.

3. The hydrogel according to claim 1, wherein the boron derivative is a sodium pentaborate pentahydrate.

4. The hydrogel according to claim 1, wherein a mixture of the gel, the boron compound and the poloxamer are stored at 4 C. for 16-24 hours before it can be used.

5. The hydrogel according to claim 1, wherein the boron compound is a boric acid.

6. The hydrogel according to claim 1, wherein the boron compound is alkaline metal borates.

7. The hydrogel according to claim 1, wherein the boron compound is alkaline earth metal borates.

8. The hydrogel according to claim 1, wherein the form of the hydrogel is selected from a group consisting of lotion, cream, emulsion, spray, foam, gelatin, paste, powder, plaster, skin plate, and wound dressing textile product.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Polymer based hydrogel developed to fulfill the objectives of the present invention is illustrated in the accompanying figures, in which:

(2) FIG. 1 shows the effect of the combination of 15 g/ml NAB and poloxamer on L929 cell viability (NAB: Sodium pentaborate pentahydrate; NAB+Poloxamer: Gel).

(3) FIG. 2 shows the time dependent effect of 15 g/ml NAB and poloxamer combinations on L929 cell viability (NAB: Sodium pentaborate pentahydrate; NAB+Poloxamer: Gel).

(4) FIG. 3 shows the effect of the gel combination and sodium pentaborate pentahydrate, which is used as the active ingredient, at eight different high concentrations in the range of 1-8 mg/ml on L929 cell viability.

(5) FIG. 4 shows the effect of sodium pentaborate pentahydrate, which is used as the active ingredient in the gel combination, at nine different high concentrations in the range of 10-200 g/ml on human fibroblast cell viability.

(6) FIG. 5 is the view of the effect of the gel combination and different combinations of the molecules used in the combination on L929 in vitro wound closure.

(7) FIG. 6 is the view of in vitro wound closure on human fibroblast cells.

(8) FIG. 7 is the view of results of in vitro wound closure of (a) L929/HUVEC co culture, (b) keratinocyte, and (c) human fibroblast wound closure.

(9) FIG. 8 is the view of the results of (a) Akt, (b) Bax and (c) p53 gene levels.

(10) FIG. 9 is the view of the results of (a) glutathione peroxidase, (b) superoxide dismutase and (c) malondialdehyde levels.

(11) FIG. 10 is the view of karyotype analysis results of human fibroblast cells.

DETAILED DESCRIPTION OF THE INVENTION

(12) In the study of the present invention, a wound healing gel formulation is developed by combining poloxamer polymers and boron component in a carbopol based gel.

(13) Experimental Study

(14) Preparation of the Gel

(15) The gel which will be used as a carrier for the active molecules, is prepared by using 1% carbopol. In preparation of the gel, the distilled water, to which 1% carbopol is added, is left for hydration at room temperature. In the process of hydratation, carbopol is gelated by adding 1.6 grams of 18% NaOH to a completely water saturated 1 liter solution. 3% boron compound and 4% poloxamer were added to the gel mixture which was homogenized by mixing after hydratation was completed. The mixture was stored at 4 C. for 16-24 hours and made ready for use.

(16) In the preparation of the hydrogel of the present invention, sodium pentaborate pentahydrate was specially preferred as the boron compound. Apart from this compound; boric acid, alkaline and alkaline earth metal borates and all hydrate forms of these borates, ammonium borates, boric acid esters can also be used.

(17) Analysis Studies

(18) Disc Diffusion Method

(19) Antimicrobial property of the developed hydrogel composition was tested according to disc diffusion method which is described previously in the literature (Lalitha and Vellore, 2005). The 100 l solution containing 10.sup.8 cfu/mil of bacteria, 10.sup.6 cfu/ml of yeast and 10.sup.4 spore/ml of fungi was prepared with new cultures and was inoculated with spreading method on Nutrient Agar (NA), Sabouraud Dextrose Agar (SDA) and Potato Dextrose Agar (PDA), respectively. 20 l hydrogel combination was introduced on the empty discs which were then placed on the inoculated media. Hydrogel not containing the active ingredient was used as the negative control. As for positive control. Ofloxacin (10 g/disc) and nystatin (30 g/disc) were used for bacteria and fungi, respectively. The inoculated petri dishes were incubated for 24 hours for bacteria and 48 hours for yeasts at 361 C. and 72 hours for fungi at 251 C. Antimicrobial activity against microorganisms tested in disc diffusion method was assessed by measuring the inhibition zone.

(20) Determining Cell Toxicity

(21) Toxic effect of the prepared gel combination was determined by using the MTS (3-(4,5-dimethyl-thiazol-2-yl)-5-(3-carboxy-methoxyphenyl)-2-(4-sulfo-phenyl)-2H-tetrazolium) method given. In the literature (Yalvac et al., 2009). The molecules used in the gel were prepared alone or in combination in the medium and applied on the L929 (Mouse Fibroblast), HF (Human Fibroblast) and human keratinocyte cell lines which were seeded on 96-well culture plates (5000 cells/well) by counting. The response of the cells to toxicity of the molecules was determined by measuring cell viability for 3 days. Cell viability was determined by using a method called MTS which measures mitochondrial dehydrogenase enzyme activity of the cell. The MTS substance added onto the cells together with the medium results in colored formazan crystals formation as an indicator of cell viability. The resulting color change was evaluated based on the absorbance measurement, by using ELISA plate reader (FIG. 1, 2, 3, 4, 5). The obtained results were analyzed.

(22) Wound Healing Scratch Model

(23) In order to determine the effect of the gel on wound healing, its capacity for cell migration and wound closure was analyzed by using the scratch assay described in the literature (Walter et al. 2010). In in vitro wound healing model, L929 (Mouse Fibroblast), HF (Human Fibroblast) and human keratinocyte cell lines and L929-HUVEC co-culture were used. The cells were seeded onto 12 well culture plates at a concentration of 100,000 cells/well, and by storing them in a carbon dioxide incubator so that they were enabled to attach and reach the sufficient density. Scratches were formed by using 200 l pipette tip such that they will be perpendicular to the horizontal lines drawn by an acetate pen from the center of the wells to the outside of the wells. Gel combination was applied on the cells and scratch closure was observed. Setrach closure (FIG. 6-7) was analyzed by using NIH Image program upon photographing the regions of the straches which correspond to the lines drawn by an acetate pen and which are in the field of view of the microscope at 0, 12 and 24 hours.

(24) Real Time PCR

(25) Real time PCR (Polymerase Chain Reaction) analyses were performed according to the literature by using SYBR Green method (Yalvac et al, 2010). The primers belonging to the collagen, fibronectin, laminin, Akt, Bax and P53 genes were designed using Primer BLAST software (The National Center for Biotechnology=NCBI). Total RNAs were isolated from the cells on which gel combination was applied and cDNA was synthesized. The synthesized cDNAs were mixed with primers in SYBR Green mix solution such that the final volume will be 20 l and the expression levels of the genes (FIG. 8) were analyzed by using BIO-RAD device.

(26) Examination of Oxidative Stress Parameters

(27) Antioxidant parameters were determined by glutathione peroxidase and superoxide dismutase enzyme activity assay and analysis of the MDA (malondialdehyde) levels. The cells which were subjected to the gel combination, to the active agent and only to the medium for control purposes in 6-well culture plates were collected and protein isolation was performed from the cell pellet by determined by measuring absorbance and drawing a standard curve at 595 nm wavelength with Bradford solution in 96-well ELISA plates by using bovine albumin protein standards (0.125, 0.25, 0.5, 0.75, 1.0, 1.5, 2.0 mg/ml). The enzyme activity assays and MDA levels were determined such that they wilt comply with the protocols given in commercials kits (FIG. 9).

(28) Chromosomal Analyses

(29) Whether the gel combination causes chromosomal anomaly was determined by using cyto-genetic analyses according to the literature (Yalvac et al., 2011). The cells were grown to a concentration of 50% in T-75 cell culture plates such that there is an active ingredient group and control group. The cells were primarily stored in a chromosome dissolving solution for 2.45 hours and then in a metaphase arresting solution for 75 minutes. After the cells were collected with trypsin, they were fixed with Carney fixative, spread on glass slides, incubated at 65 C. overnight, stained with Giemsa and metaphase appearances thereof were analyzed by means of a light microscope (FIG. 10).

(30) Experimental Results

(31) In vitro cell viability analyses were performed on L929 cells (mouse fibroblast cells) with the purpose of determining the toxic effects of the molecules, alone or in combination, in the gel mixture composed of sodium pentaborate pentahydrate and poloxamer polymer combination. It was observed that 15 g/ml sodium pentaborate pentahydrate and poloxamer mixture, which was used in the preparation of the gel, did not have toxic effect on the mouse fibroblast cells used as model cells in wound healing experiments. After the MTS analyses that were performed for a period of three days, it was determined that the gel combination and the substances used in its composition did not have toxic effect (FIG. 1).

(32) The toxicity analyses were repeated in order to find out the time dependent effect and the suitable metabolization period for the gel with the concentrations and combinations used in cell viability analyses. MTS experiments were made with L929 cells at 3, 6, 9 and 12 hours and optimum activity period was determined. After the analyses, it was determined that the application of 9 hours was the time period in which maximum activity was observed (FIG. 2).

(33) With the purpose of finding out whether sodium pentaborate pentahydrate used as an active ingredient within the gel combination has negative effects on cell viability at high concentrations in in vitro conditions, toxicity analyses were conducted for three days for the gel mixture prepared within carbopol used as 8 different concentrations ranging between 1 and 8 mg/ml and a carrier molecule. When analyzed statistically, a significant amount of toxic effect was determined at concentrations higher than 5 mg/ml (FIG. 3).

(34) Following the toxicity analyses conducted on mouse fibroblast cells, cell viability analyses on human fibroblast cell line were completed as well. Cell viability analyses were conducted on human fibroblast in in vitro conditions by using nine different concentrations ranging between 10 and 200 g/ml. No toxic effect was observed at the applied concentrations (FIG. 4).

(35) In in vitro conditions, wound healing assay was performed by scratching the cells which are growing as a single layer and analyzing healing by photographing the wound area at certain time periods. A wound closure experiment was conducted with L929 cells in in vitro conditions in order to determine the activity of the prepared gel formulation on wound healing. The wound area was analyzed by NIH image program by photographing the wound are at 0, 12 and 24 hours. While in the first 12 hour period, sodium pentaborate pentahydrate used as active ingredient in the gel was more effective than the gel combination; at the end of 24 hour monitoring, it was determined that the gel combination substantially increased wound closure. At the end of 12 hours, approximately 49% closure was observed at the control group, while 71% and 64% closures were observed at the group to which sodium pentaborate pentahydrate and the gel combination were administered, respectively. At the end of 24 hours, while the wound closure rate of the control group was 75%, in the groups to which sodium pentaborate pentahydrate and gel combination were administered the wound closure rates were measured as 84% and 91%, respectively (FIG. 5).

(36) In vitro wound healing experiments were repeated by using human fibroblast cells. Wound closure was analyzed by taking photographs at 12 and 24 hours. When the wound closure rates were analyzed, it was determined that sodium pentaborate pentahydrate used in the gel was more effective on wound healing than the control group and get combination. At the end of a 12 hour period of time, the wound closure rate of the control group was determined as 39%, while the wound closure rates of the groups to which sodium pentaborate pentahydrate and gel combination were administered were 58% and 54%, respectively. At the end of 24 hours, the wound closure rate of the control group was measured as 67%, while the wound closure rates of the groups to which sodium pentaborate pentahydrate and gel combination were administered were measured as 91% and 85%, respectively (FIG. 6).

(37) Co-culture experiments were conducted to mimic the wound healing in the skin. Wound healing was analyzed by culturing L929 mouse fibroblast ceils and HUVEC endothelial cells in in vitro conditions. At the end of a 12 hour period of time, the wound closure rate of the control group was determined as 41%, while the wound closure rates of the groups to which sodium pentaborate pentahydrate and gel combination were administered were determined as 59% and 54%, respectively. At the end of 24 hours, the wound closure rate of the control group was measured as 76%, while the wound closure rates of the groups to which sodium pentaborate pentahydrate and gel combination were administered were measured as 100% and 97%, respectively. It was determined that the active ingredient sodium pentaborate pentahydrate and the gel combination were more effective on wound healing in comparison to the control group (FIG. 7).

(38) Real time PCR analyses were conducted in order to show the activity of the prepared gel combination on wound healing in gene expression level. The analyses conducted at gene expression level were completed by analyzing the genes affecting cell migration and the apoptotic genes. The decrease in the Akt gene levels is a factor that affects the wound closure in the cells and the decrease in the gene level is an indicator of the increase in cell migration (Jones et al., 2010). Bax and p53 genes play roles in apoptotic mechanism and the decrease in their expression levels is considered as an indicator of cell proliferation. The results of the analysis that was conducted showed that the gel combination and the active molecule used in the combination decreased apoptotie gene levels and akt gene levels (FIG. 8).

(39) Oxidative stress is a factor which is effective in wound healing process and skin aging. With the activity of various antioxidant enzymes, the reactive oxygen species produced in the body and their harmful effects are eliminated. The effect of the gel combination developed in the present invention on antioxidant enzyme activity was determined by measuring the glutathione peroxidase, superoxide dismutase (SOD) and malondialdehyde (MDA) levels. Glutathione peroxidase, superoxide dismutase and malondialdehyde are used in the literature in wound healing studies as an indicator for observing the effects of oxidative stress. SOD converts superoxide ion to hydrogen peroxide and the resulting hydrogen peroxide is converted to water with glutathione peroxidase in lysozyme. Furthermore, MDA is also produced as a result of lipid peroxidation and causes mutations upon interacting with DNA. The increase in glutathione peroxidase and superoxide dismutase enzyme activity and the decrease in MDA level are considered as indicators of an effective wound healing (Bayati and Abdulla, 2012). The fact that glutathione peroxidase has protective effect in the inflammation step of wound healing is proved in the studies conducted (Munz et al., 1997). The glutathione peroxidase activity is indirectly measured by analyzing NADPH (Nicotinamide Adenine Dinucleotide Phosphate) oxidation based on absorbance. A substantial amount of enzyme activity was determined in the gel combination and sodium pentaborate pentahydrate groups in comparison to the control group. Superoxide dismutase enzyme activity was determined indirectly. The high level of enzyme activity was observed in the gel combination and sodium pentaborate pentahydrate groups.

(40) When malondialdehyde levels, which are indicators of lipid peroxidation, were analyzed, low MDA levels were observed in the gel combination and sodium pentaborate pentahydrate groups in comparison to the control group. When oxidative stress parameters were examined, it was determined that sodium pentaborate pentahydrate group alone was more effective then the gel combination (FIG. 9).

(41) Karyotype analyses were conducted in order to determine whether the prepared gel combination caused a chromosomal anomaly on the cells. The results showed that when sodium pentaborate pentahydrate and gel combination were applied, the cells maintained their normal karyotypes (FIG. 10).

(42) By using the Polymer based hydrogel of the present invention; lotion, cream, emulsion, spray, foam, gelatin, paste, powder or plasters, skin plate and wound dressing textile products can be developed in different therapeutic compositions which are antimicrobial (antibacterial, anticandidal, antifungal) and fast wound healing, and which prevent formations of wrinkles and scars.

(43) All kinds of perfumes, moisturizers and surfactants, which will not chemically interact with the products in the formulations, can be added to the said hydrogel at suitable concentrations such that they will not reduce the antimicrobial, wound healing and anti-aging properties thereof.

(44) The hydrogel formulation disclosed in the present patent document can be used in all medical products, personal care products, cosmetic applications, drug formulations and medical applications upon being optimized.