rus
Issue #3-4/2023
G.E.Krichevsky, N.D.Oltarzhevskaya, M.A.Shchedrina, Y.S.Fidorovskaya
NANOMEDICINE. THE USE OF BIOSYNTHETICALLY PRODUCED METAL NANOPARTICLES IN A NEW GENERATION OF WOUND-HEALING DEPOTMATERIALS DEVELOPMENT
NANOMEDICINE. THE USE OF BIOSYNTHETICALLY PRODUCED METAL NANOPARTICLES IN A NEW GENERATION OF WOUND-HEALING DEPOTMATERIALS DEVELOPMENT
DOI: https://doi.org/10.22184/1993-8578.2023.16.3-4.196.202
Nanotechnology, as an interdisciplinary and cross-sectoral technology, is now used worldwide in almost all fields of science and technology and in all branches of modern industry. The value of products derived from nanotechnology amounts to trillions of dollars. Nanotechnology is also being used effectively in all fields of medicine. New fields have appeared and consolidated: nanomedicine, nanotherapy, nanodiagnostics. Nanoparticles of various natures have a special place in medicine. This paper is devoted to practical use of silver nanoparticles in wound healing of purulent wounds. The effectiveness of the developed application containing silver nanoparticles and enzymes is presented.
Nanotechnology, as an interdisciplinary and cross-sectoral technology, is now used worldwide in almost all fields of science and technology and in all branches of modern industry. The value of products derived from nanotechnology amounts to trillions of dollars. Nanotechnology is also being used effectively in all fields of medicine. New fields have appeared and consolidated: nanomedicine, nanotherapy, nanodiagnostics. Nanoparticles of various natures have a special place in medicine. This paper is devoted to practical use of silver nanoparticles in wound healing of purulent wounds. The effectiveness of the developed application containing silver nanoparticles and enzymes is presented.
INTRODUCTION
Nanotechnology (NT) is organically included in science and technology cluster NBICS (nano-, bio-, cognitive-, socio-technology) as one of the determinants of civilization development in the 21st century [1, 2]. Medicine, as life science, is a priority area of NBICS practical application. Nanotechnology plays a great role in development of modern medicine, forming all new directions and terms: nanomedicine, nanotherapy, nanodiagnostics, etc. NT has penetrated into almost all fields of medicine and is used at all hierarchical levels of a living organism – molecular, cellular, intercellular, tissue (organs) and, finally, a body as a whole [3].
Nanoparticles of various nature and species are widely used in all fields of medicine. One of the most advanced areas of modern medicine is the targeted delivery of drugs to pathogenic cells and organs using nanocarriers. Nanocarriers load drugs and deliver them to the damaged organs, tissues and cells without lingering in healthy tissues. This eliminates, where possible, the side (sometimes toxic) effects of the drugs along the nanotransporters route through the human body.
An important place in NT is occupied by noble and heavy metal nanoparticles (MNP), which have unique properties that allow their effective use both in various fields of science and technology (optics, catalysis, environmental protection, agricultural engineering, modern packaging) and in many areas of medicine. Table 2 shows which diseases can be treated using MNPs [3].
MNPs are widely used both in nanotherapy of many diseases and in modern nanodiagnostics. Nanotherapy with MNPs is based on their unique biological activity at the cellular and molecular level. MNPs are universal biocides that "beat" all pathogenic microorganisms and viruses, as well as their colonies. Upon contact with the cell wall of the microorganism, MNPs interact with one of the components of the wall, glycoprotein, destroying a wall and penetrating inside a cell, where they then interact with most of the major components of the cell (DNA, RNA, enzymes, etc.) This results in a destructive oxidative stress (ROS) in the cell. All these transformations stop cell growth because the heredity apparatus is destroyed (see Fig.1).
This destructive effect of MNPs occurs in relation to all types of cells. If they come into contact with pathogenic microorganisms (bacteria, fungi), with viruses, their growth stops and, moreover, they die at certain concentrations of MNPs. There is a similar mechanism of interaction of MNPs with oncocytes, towards which MNPs act as cytostatics, suppressing growth of oncocytes [3]. Unfortunately, in a number of cases, MNPs in contact with healthy cells also suppress the growth and even kill them, i.e. act as toxic substances. This situation must be taken into account when using MNPs in various types of therapy, avoiding toxicity if possible by selecting optimal concentrations of MNPs.
The MNPs properties, including bioactivity, depend significantly on their morphology (particle size, shape) [2]. Therefore, it is useful to always specify these parameters when describing an experiment.
This paper will focus on the use of MNPs for healing chronic wounds, a disease that is very common and problematic throughout the world, bringing great suffering to people and enormous costs to solve this economic and social problem (loss of quality of life, disability, costly treatment).
The problem is now exacerbated by the number of military conflicts, technological disasters. There are now 1.5–2 million people in Europe suffering from chronic wounds, with £5 billion spent annually in the UK and up to $25 billion in the US on treating the disease.
Development of a new generation of wound healing agents using MNPs
The treatment of chronic wounds is based on the knowledge of the natural multistage healing process; to be effective, the wound must first be cleared of protein breakdown products, which is done mechanically or by enzymes, reducing viscosity of discharge and evacuating it from the wound, then the inflammatory process, determined by pathogens, is tackled, followed by the repair (regeneration) of damaged tissue. In real life, it is not possible to completely separate one stage from the other, although treatment process most often uses wound lysis agents sequentially followed by antimicrobials.
Silver nitrate was chosen as the antimicrobial component due to its wide range of antimicrobial activity, but conversion of the silver nitrate precursor into nanoform was important to achieve effective treatment and reduce toxicity. Local targeted delivery of silver cations and nanoparticles to the lesion site was envisaged, for which a textile material made of hydrophilic viscose fibres was applied to the wound with a viscous hydrogel composition made of natural biopolymer-polysaccharide sodium alginate and silver nitrate salt introduced on one side of it. The choice of sodium alginate is not accidental. In addition to its important properties for use in medicine – anti-allergenicity, haemostatic properties, high content of trace elements contributing to tissue regeneration – alginate in this case plays the role of reducing silver cations to nanoparticles, i.e. becomes a kind of bioreactor, and also acts as a colloidal stabilizer of metal particles nanodispersions. To enhance reduction of silver ions to nanoparticles, alkali in the form of sodium carbonate was introduced into the polymer composition. In addition to indicated function, as evidenced by the appearance of a brown tint to composition, an alkaline environment at pH 7.0–8.5 favours wound healing. To prove the nanoparticles formation under these conditions, an alginate composition (composition 0.05%, 0.1M AgNO3, 6% sodium alginate) applied to the surface of a fresh mica chip was examined by probe microscopy; the study confirmed formation of silver nanoparticles, crystallized as tetrahedrons up to 50 nm in height. Transfer of silver cations into the nanoform was approximately 80 %; however, due to the higher bactericidal activity of the nanoform, the larger contact surface with pathogenic microflora, the effect is higher than that of metal cations and is achieved at a lower concentration of silver nitrate; silver cations, also with bactericidal activity, are involved in the antimicrobial action.
The desirable simultaneous effect of both stages of the wound process – lysis of wound discharge and antimicrobial effect – in treatment of long-term non-healing wounds was mentioned earlier. The natural proteolytic enzyme papain was used to achieve lysis of purulent secretions, which has a rather mild effect on the tissue and acts in a wide pH and temperature range. It was necessary to evaluate the possible effect on the joint use of papain and silver ions on the transition of the latter to the nanoform and decrease of the enzyme activity, as undesirable interaction between metal cations and enzymes is known [4]. Formation of silver nanoparticles in the above composition (in the presence of particles in ionic form) was confirmed by probe microscopy, and determination of papain activity by the Anson method showed its preservation, and proposed introduction of a second polymer, namely, hydroxypropyl methylcellulose, into the composition allowed the enzyme to be protected even in the case of the mandatory for medical products gamma sterilization operation, preserving rheological parameters of composition.
Thus, all components of the medical product created (Coletex ASP wipe, RZN approval for wide use) have a therapeutic effect: simultaneous presence of an enzyme and a biocide can affect different parts of the wound process to clean the wound and eliminate the purulent inflammatory focus, sodium alginate biopolymer helps to create a desired pH in the wound for healing, leads to increased regeneration processes, the textile material protects the wound from external influences, sorbs the wound.
Figure 2 shows the results of the chronic wound treatment in the middle third of the thigh. Within three weeks there is complete clearing of the wound, reduction of its area, reparative tissue regeneration and closure of the soft tissue defect (without surgical treatment).
CONCLUSIONS
A new generation of domestic therapeutic depot material containing silver nanoparticles (universal biocide) and natural papain enzyme has been developed;
the therapeutic depo-material obtained using this technology allows effective treatment of chronic wounds that are difficult to heal, which has been confirmed in clinical conditions.
PEER REVIEW INFO
Editorial board thanks the anonymous reviewer(s) for their contribution to the peer review of this work. It is also grateful for their consent to publish papers on the journal’s website and SEL eLibrary eLIBRARY.RU.
Declaration of Competing Interest. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Nanotechnology (NT) is organically included in science and technology cluster NBICS (nano-, bio-, cognitive-, socio-technology) as one of the determinants of civilization development in the 21st century [1, 2]. Medicine, as life science, is a priority area of NBICS practical application. Nanotechnology plays a great role in development of modern medicine, forming all new directions and terms: nanomedicine, nanotherapy, nanodiagnostics, etc. NT has penetrated into almost all fields of medicine and is used at all hierarchical levels of a living organism – molecular, cellular, intercellular, tissue (organs) and, finally, a body as a whole [3].
Nanoparticles of various nature and species are widely used in all fields of medicine. One of the most advanced areas of modern medicine is the targeted delivery of drugs to pathogenic cells and organs using nanocarriers. Nanocarriers load drugs and deliver them to the damaged organs, tissues and cells without lingering in healthy tissues. This eliminates, where possible, the side (sometimes toxic) effects of the drugs along the nanotransporters route through the human body.
An important place in NT is occupied by noble and heavy metal nanoparticles (MNP), which have unique properties that allow their effective use both in various fields of science and technology (optics, catalysis, environmental protection, agricultural engineering, modern packaging) and in many areas of medicine. Table 2 shows which diseases can be treated using MNPs [3].
MNPs are widely used both in nanotherapy of many diseases and in modern nanodiagnostics. Nanotherapy with MNPs is based on their unique biological activity at the cellular and molecular level. MNPs are universal biocides that "beat" all pathogenic microorganisms and viruses, as well as their colonies. Upon contact with the cell wall of the microorganism, MNPs interact with one of the components of the wall, glycoprotein, destroying a wall and penetrating inside a cell, where they then interact with most of the major components of the cell (DNA, RNA, enzymes, etc.) This results in a destructive oxidative stress (ROS) in the cell. All these transformations stop cell growth because the heredity apparatus is destroyed (see Fig.1).
This destructive effect of MNPs occurs in relation to all types of cells. If they come into contact with pathogenic microorganisms (bacteria, fungi), with viruses, their growth stops and, moreover, they die at certain concentrations of MNPs. There is a similar mechanism of interaction of MNPs with oncocytes, towards which MNPs act as cytostatics, suppressing growth of oncocytes [3]. Unfortunately, in a number of cases, MNPs in contact with healthy cells also suppress the growth and even kill them, i.e. act as toxic substances. This situation must be taken into account when using MNPs in various types of therapy, avoiding toxicity if possible by selecting optimal concentrations of MNPs.
The MNPs properties, including bioactivity, depend significantly on their morphology (particle size, shape) [2]. Therefore, it is useful to always specify these parameters when describing an experiment.
This paper will focus on the use of MNPs for healing chronic wounds, a disease that is very common and problematic throughout the world, bringing great suffering to people and enormous costs to solve this economic and social problem (loss of quality of life, disability, costly treatment).
The problem is now exacerbated by the number of military conflicts, technological disasters. There are now 1.5–2 million people in Europe suffering from chronic wounds, with £5 billion spent annually in the UK and up to $25 billion in the US on treating the disease.
Development of a new generation of wound healing agents using MNPs
The treatment of chronic wounds is based on the knowledge of the natural multistage healing process; to be effective, the wound must first be cleared of protein breakdown products, which is done mechanically or by enzymes, reducing viscosity of discharge and evacuating it from the wound, then the inflammatory process, determined by pathogens, is tackled, followed by the repair (regeneration) of damaged tissue. In real life, it is not possible to completely separate one stage from the other, although treatment process most often uses wound lysis agents sequentially followed by antimicrobials.
Silver nitrate was chosen as the antimicrobial component due to its wide range of antimicrobial activity, but conversion of the silver nitrate precursor into nanoform was important to achieve effective treatment and reduce toxicity. Local targeted delivery of silver cations and nanoparticles to the lesion site was envisaged, for which a textile material made of hydrophilic viscose fibres was applied to the wound with a viscous hydrogel composition made of natural biopolymer-polysaccharide sodium alginate and silver nitrate salt introduced on one side of it. The choice of sodium alginate is not accidental. In addition to its important properties for use in medicine – anti-allergenicity, haemostatic properties, high content of trace elements contributing to tissue regeneration – alginate in this case plays the role of reducing silver cations to nanoparticles, i.e. becomes a kind of bioreactor, and also acts as a colloidal stabilizer of metal particles nanodispersions. To enhance reduction of silver ions to nanoparticles, alkali in the form of sodium carbonate was introduced into the polymer composition. In addition to indicated function, as evidenced by the appearance of a brown tint to composition, an alkaline environment at pH 7.0–8.5 favours wound healing. To prove the nanoparticles formation under these conditions, an alginate composition (composition 0.05%, 0.1M AgNO3, 6% sodium alginate) applied to the surface of a fresh mica chip was examined by probe microscopy; the study confirmed formation of silver nanoparticles, crystallized as tetrahedrons up to 50 nm in height. Transfer of silver cations into the nanoform was approximately 80 %; however, due to the higher bactericidal activity of the nanoform, the larger contact surface with pathogenic microflora, the effect is higher than that of metal cations and is achieved at a lower concentration of silver nitrate; silver cations, also with bactericidal activity, are involved in the antimicrobial action.
The desirable simultaneous effect of both stages of the wound process – lysis of wound discharge and antimicrobial effect – in treatment of long-term non-healing wounds was mentioned earlier. The natural proteolytic enzyme papain was used to achieve lysis of purulent secretions, which has a rather mild effect on the tissue and acts in a wide pH and temperature range. It was necessary to evaluate the possible effect on the joint use of papain and silver ions on the transition of the latter to the nanoform and decrease of the enzyme activity, as undesirable interaction between metal cations and enzymes is known [4]. Formation of silver nanoparticles in the above composition (in the presence of particles in ionic form) was confirmed by probe microscopy, and determination of papain activity by the Anson method showed its preservation, and proposed introduction of a second polymer, namely, hydroxypropyl methylcellulose, into the composition allowed the enzyme to be protected even in the case of the mandatory for medical products gamma sterilization operation, preserving rheological parameters of composition.
Thus, all components of the medical product created (Coletex ASP wipe, RZN approval for wide use) have a therapeutic effect: simultaneous presence of an enzyme and a biocide can affect different parts of the wound process to clean the wound and eliminate the purulent inflammatory focus, sodium alginate biopolymer helps to create a desired pH in the wound for healing, leads to increased regeneration processes, the textile material protects the wound from external influences, sorbs the wound.
Figure 2 shows the results of the chronic wound treatment in the middle third of the thigh. Within three weeks there is complete clearing of the wound, reduction of its area, reparative tissue regeneration and closure of the soft tissue defect (without surgical treatment).
CONCLUSIONS
A new generation of domestic therapeutic depot material containing silver nanoparticles (universal biocide) and natural papain enzyme has been developed;
the therapeutic depo-material obtained using this technology allows effective treatment of chronic wounds that are difficult to heal, which has been confirmed in clinical conditions.
PEER REVIEW INFO
Editorial board thanks the anonymous reviewer(s) for their contribution to the peer review of this work. It is also grateful for their consent to publish papers on the journal’s website and SEL eLibrary eLIBRARY.RU.
Declaration of Competing Interest. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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