ADDITIVE BASED ON MICRO AND NANO PARTICLES OF ZINC, SILVER AND COPPER METAL, USEFUL FOR IMPARTING VIRICIDAL ACTIVITY TO A POLYMER MATRIX

Abstract

Provided is an additive based on micro and nano particles of zinc, silver and copper metal for preparing a polymer material with antiviral and virucidal properties. The material is used to form or produce surfaces, containers of all types, garments, safety equipment, fabrics, paints, coatings or other items and reduces the growth or presence of respiratory viruses.

Claims

1. The invention relates to a master batch for preparing a material with antiviral and virucidal properties, characterized in that it comprises: (i) a polymeric material selected from low density polyethylene (PE), high density polyethylene (HDPE), linear density polyethylene (LLDPE), polypropylene (PP), polyethylene terephthalate (PET), copolyester 5011 (modified PET or PETG), polycarbonate (PC), polymethylmethacrylate (PMMA), starch mixtures, polytrimethylene terephthalate (PTT), vinyl polychloride (PVC), polystyrene (PS), polybutylene terephthalate (PBAT), polycaprolactone (PCL) and polylactic acid (PLA), at a concentration of 65 and 98.5% w/w until 100% of the mixture is completed. (ii) copper, zinc or metal silver particles at 1 to 25% w/w, wherein said particles have a purity of 99, 98 to 100%, without presenting oxygen or sulfides in their composition and present a size of 0, 1 to 100 microns. (iii) Additives such as glycerol monostearate, glycerol ester, sorbitol ester, alcaloxylated ester, oleochemical derivatives, amines and their derivatives, wherein the amines are selected from ethoxylated amines, ethoxylated alkyl amines (C13 to C15 ethoxylated alkyl amine) at concentrations of 0.5 and 10% w/w of the total master batch.

2. A master batch for preparing a material with antiviral and virucidal properties according to claim 1 wherein the polymeric material is selected from polyethylene and polyethylene terephthalate.

3. A master batch for preparing a material with antiviral and virucidal properties according to claim 1 wherein the copper particles have a size of 0.3 to 40 microns.

4. A master batch for preparing a material with antiviral and virucidal properties according to claim 1 wherein the metallic copper particles are at a concentration of 5-15% w/w

5. A master batch for preparing a material with antiviral and virucidal properties according to claim 1 wherein the metallic copper particles are at a concentration of 10% w/w

6. A master batch for preparing a material with antiviral and virucidal properties according to claim 1 wherein the additives are in a concentration of 0.5 to 10%.

7. A master batch for preparing a material with antiviral and virucidal properties according to claim 1 wherein the additives are in a concentration of 1 to 3%.

8. Polymeric material with antiviral and virucidal properties characterized in that it is composed or made with the masterbatch described in claims 1 to 7.

9. Polymeric material with antiviral and virucidal properties characterized in that it is composed or made with the masterbatch described in claims 1 to 7 and is in the form of pellets, yarns, plates, blades, leaves or the other.

10. Use of the polymeric material with antiviral and virucidal properties according to claims 8 and 9 characterized in that it serves to form or make surfaces, containers of all types, garments, safety implements, fabrics, paints and coatings or others.

11. Use of the polymeric material with antiviral and virucidal properties according to claim 10 which serves to decrease the growth or presence of respiratory viruses.

12. Use of the polymeric material with antiviral and virucidal properties according to claims 10 and 11 characterized in that it serves to decrease the growth or presence of human influenza virus respiratory viruses and SARS-COV2.

Description

DESCRIPTION OF THE FIGURES

[0048] FIG. 1. Virucidal effect of polymeric materials. The virucidal effect of two polymeric materials can be seen in the figure. It is represented in the virucidal effect in percent of viral load decrease. Where () corresponds to the polymeric material used as a control comprising polymer and metallic copper, () corresponds to the polymeric material described herein.

[0049] FIG. 2. Counting viral genomes from SARS-CoV-2 synthetic samples for calibration curve. The amplification of the SARS-COV-2 nucleocapsid gene in the synthetic viral samples is presented in the graph. It can be seen that the amplification has a number of equivalent copies a range of I×l O4 and I×l O6. y=68, 87x.sup.˜0′027 corresponds to the equation of the straight for this analysis.

[0050] FIG. 3. Counting of SARS-CoV-2 viral genomes from patient samples. The number of viral genomes obtained after incubation of the viral sample in the PET polymer matrix is presented in the graph. Where, () indicates the incubation for 1 hour, () indicates incubation for 4 hours and () indicates incubation for 12 hours. All incubations were performed at room temperature.

[0051] FIG. 4. Standardization of the damage produced by UV light in the genetic material of the virus. Figure (Cq) cycles of viral RNA exposed to UV light from 0 to 60 minutes are presented.

[0052] FIG. 5. Virucidal effect of PE and PET polymeric materials. The effect of polymer matrices copper SARS-CoV-2 samples is presented in the figure. It indicates the control of viral growth, PE_natural corresponds to PE without copper treatment, PET_virgin corresponds to PET without copper treatment, PE 9919-50% and PET_9927-50% correspond to PE and PET with 50% masterbatch, dotted lines indicate that there was no amplification of genetic material.

EXAMPLES OF APPLICATION

Example 1. Preparation of Polymeric Matrix with Virucidal Activity

[0053] This procedure is performed for obtaining a homogeneous polymeric matrix having virucidal activity.

[0054] The method for obtaining a virucidal polymeric matrix consists of the following steps: [0055] 1) Premix: At this stage the copper particles are mixed with the additives. Initially the metal is added with the additives, using a model TRR300 turbo mixer soft mix equipment, the initial mixture being performed at low speed in 3 cycles of 30 seconds, once this mixture is terminated, aqueous dispersion additives are added and mixed for 2 cycles of 90 seconds allowing excess additive and residual moisture to be removed. The additives should melt in a range of temperatures between 90 and 120° C. to achieve the additives to coat the metal particles. [0056] 2) drying: step wherein the premix is dried under oxygen absence conditions by preventing oxidation of the metal using a modified furnace to allow drying in the absence of oxygen. At this stage a modified furnace was used in the absence of oxygen; for this, oxygen from the nitrogen drying chamber is removed prior to entering the mixture for drying thereby eliminating residual moisture by maintaining the purity of the particulate metal so that it can react and release ions at their maximum capacity. This process is performed at atmospheric pressure, at a temperature ranging between 100° C. and 120° C. for a period ranging between 30 and 60 minutes, both of the above parameters being fixed according to the amount of additive and residual moisture present the mixture. [0057] 3) Preparation of the polymer matrix: where the dry premix is incorporated with the polymer to form a masterbatch in this latter step processes such as dosing, extrusion, cutting, prilling, sorting, drying and packaging are used. Particularly, an extrusion process is performed using a Coperion ZSK 18 extrusion equipment or the like with gravimetric dosing. In this process the masterbatch is produced The dosing system includes at least three gravimetric dosages with the possibility of entering the copper/additive mixture to the process, once the polymer is melted and in the zone designed for this purpose, with a geometry of spindles specifically designed for this purpose. The extrusion temperature ranges from 180° C. to 160° C. it is very important to work with vacuum system, with a minimum pressure of −0.8 bar, to ensure removal of volatiles and remaining impurities. For each polymer the temperatures vary and move in ranges between 20 to 30° C. over the polymer melt temperature. Finally, the material is dry cooled, to avoid the presence of moisture, for them a vented conveyor belt is used, then the material obtained is cut into a pelletizer. Said pellet-shaped material is dried again at 60° C. for 1 hour, to then be packaged. Such pellet-shaped material must be passed through its selection system, which ensures homogeneity of the pellets, by size selection, is then packaged in moisture and moisture barrier bags, which are hermetic and sealed.

Example 2. Evaluation of Viral Activity of the Polymer Matrix on Influenza Virus

[0058] In this example of application, procedures performed for in vitro evaluation of the virucidal activity of the polymer matrix on influenza H1N1 virus, pandemic 2009 are described.

[0059] For this assay, 10 μL of a solution containing the H1N1 influenza virus was used that were placed on different materials to compare the virucidal effect, including the polymeric material described in this invention. The assay was incubated for a period of time of 1, 4 and 12 hours, to then recover the viruses and be deposited on an MDCK cell culture. The results of such an analysis indicate that by contacting the material described in this invention with the virus reduces the viral load by up to 98%, more specifically, the viral load decreases by 94% to the 1 hour incubation, in 96% after 4 hours of incubation, reaching a viral load decrease of 98% to 12 hours of incubation (Table 1).

[0060] This assay was compared to another material used as a control, which comprises in its composition only polymer and metallic copper. The results obtained allow the polymeric material described in this invention to exhibit greater virucidal activity with respect to the control (FIG. 1, Table 1), where the latter reduced viral load to 82% over a period of 12 hours. Thus, the use of this material prepared with the polymer, amines, additives and copper metals is capable of significantly eliminating or decreasing the viral load that can be presented in this type of materials, which avoids the propagation and contact of this type of virus.

TABLE-US-00001 TABLE 1 Comparison of the decrease of viral load using different polymers. Time Título Titulo Reducción del (hour) Material TCID50 viral título viral 1 C1 978053.7 1 × 10.sup.6 M1 370084.6 4 × 10.sup.5 62% C2 97053.7 1 × 10.sup.6 M2 56234.1 6 × 10.sup.4 94% 4 C1 562341.3 6 × 10.sup.5 M1 208113.9 2 × 10.sup.5 63% C2 31622.8 3 × 10.sup.4 M2 1389.1 1 × 10.sup.3 96% 12 C1 173925.3 2 × 10.sup.5 M1 30928.8 3 × 10.sup.4 82% C2 173925.3 2 × 10.sup.5 M2 4392.8 4 × 10.sup.3 98%

[0061] The decrease in viral load using different polymers is presented in the table. C1 and C2 corresponds to the control material containing only polymer; MI corresponds to the polymer composite and metallic copper; M2 corresponds to the material described in this invention including metallic copper at a concentration of 10% and additives between 1 and 3%. the calculation for viral load reduction is performed using comparison between C1 and C2 with M1 and M2 respectively.

Example 3 Evaluation of the Virucidal Activity of the Matrix or Polymeric Material on Coronavirus

[0062] In this example of application, procedures performed for in vitro evaluation of the virucidal activity of the polymeric material of the present invention are described on SARS-Cov-2 coronavirus samples. Particularly, in this example application a polymer matrix of PE (polyethylene) and PET (polyethylene terephthalate) was used.

Preparation of Viral Samples and Incubation in Polymer Matrices.

[0063] Synthetic samples from viral solutions and nasopharyngeal samples obtained from patients counted with SARS-Cov-2 coronavirus were used for this assay.

[0064] The polymer matrices were cut with dimensions of 1.5 cm×1.5 cm and placed in 24-well plates. Each was added 300 μL of the virus sample and incubated for 2 hours at room temperature.

Nucleic Acid Extraction.

[0065] After the incubation period of the polymer matrices, the samples were again incubated with a 1:1 volume of lysis buffer for 5 minutes, then this sample is incubated with 70% ethanol (1:1 ratio) and transferred to silica columns. RNA extraction was performed using the total RNA extraction kit from Omega Biotek to obtain total RNA according to manufacturer's instructions.

[0066] RT-qPCR.

[0067] After obtaining the viral RNA, a reverse transcriptase is performed. For amplification, One-step Fast Virus Kit (Thermo Fisher Scientific) and probe (s) that detect or amplify specific regions of the virus nucleocapsid gene (N gene) was used. In addition, a set of primers for human P RNAse gene detection and corresponding reaction controls were used.

[0068] The results show that the regions of the synthetic viral genome corresponding to the nucleocapsid in a range of equivalent copies between I×104 to I×l 06 (figure) was achieved. With these results a calibration curve was made in order to relate the results to the patient samples.

[0069] After obtaining the calibration curves, an assay was performed where the samples from patients were incubated on the PET polymer matrix, thus the matrix was used without copper treatment and a matrix with copper treatment and their corresponding additives (10% copper and 2% additives). These samples were incubated at 1, 4 and 12 hours. Equivalent genomes of genomes was performed by RT-qPCR (Figure). In these results it was observed that the copper-treated PET plastic exhibits a decrease effect on the copy number of the detected viral genome, with respect to the PET matrix found without the addition of copper.

[0070] To determine that the effect on decreasing the copy number of the virus genetic material is due to the action of copper polymer matrices and not by the action of other agents, such as UV light, an assay was performed where the samples were first exposed to UV light and then RT-qPCR. This is because the exposure of the virus to UV light at the time degrades the genomes that are free in the sample thereby serving to estimate the number of genome copies found in virus with intact capsids, therefore, when performing the RT-qPCR the higher integrity of the genome to be amplified is ensured. The results of this assay show that the UV has a dependent dose effect depending on the exposure time so that a suitable dose of UV can be established for the final assay on the polymer matrices (figure).

[0071] To determine the impact on the integrity of the virus genome of copper-treated plastics was evaluated by RT-qPCR the reduction in the number of viral RNA copies over time after a controlled and unique UV exposure. For this assay PE and PET was used without additives (or virgin), PE with 50% masterbatch (PE_9919-50%), PET with 50% masterbatch

[0072] (PET_9927-50%) where the incubation period was 2 hours at room temperature (Figure). The results of this analysis indicate that PE and PET materials corresponding to PET_9927-50% and PE_9918 50% decrease the viral load by 99% over a period of 2 hours. This was determined using the calibration curve and the results of the cycles (Ct) for each of the materials.

[0073] Therefore, assays demonstrate that there is a degradation of the genetic material of the virus and the capsid of the SARS-CoV-2 virus during the exposure of these polymeric materials presenting a treatment with nano and microparticles of metallic copper and specific additives.

LITERATURE

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