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Scope of using the functional properties of fabrics to prevent the actions of different Microorganisms.


This research work has been done in Textile Coloration Lab of National Institute of Textile Engineering and Research (NITER), Fiber and Polymer Institute of Bangladesh Council of Scientific and Industrial Research and Microbiology Lab of Institute of Food and Radiation Biology (IFRB) of Atomic Energy Research Establishment.

cost-effective process for antimicrobial finishing of cotton textiles
cost-effective process for antimicrobial finishing of cotton textiles


Many antimicrobial finishing with synthetic chemicals were commonly been in used but the wash out effluent from the industry pollutes the environment and also becomes a cause for antimicrobial resistance in microbes at the exposed environment. Hence the present study is designed to identify a low temperature and cost-effective process for antimicrobial finishing of cotton textiles by using copper particle which is environment friendly. The antimicrobial treatment was performed by the formation of copper Nano particles and then treated textiles the prepared particles of copper. The antimicrobial activity was determined by using E. coli (as a model for Gram-negative bacteria), Salmonella enteridis, Bacillus subtilis and Staphylococcus aureus. The results showed that the treated textile has good antimicrobial effect and laundering durability.

Keywords: Medical textile, Antimicrobial finished textile, Copper particle, Scouring, Bleaching, Microorganisms, Antimicrobial test, fungal growth, Antimicrobial potency, etc.


The textile industry is one of the most significant and quickly developing commercial industries with good financial sources. Increasing competition around the world in textiles has given many opportunities to researchers and industry partners to find out new technological innovations to overcome the existing drawbacks. Major concerns by the industry are the quality and the durability of the fabrics. Damage to the cotton fabric are observed by the industry due to microbial attack, pilling of the threads etc. Textiles, especially those made of natural fibers, are an excellent medium for the growth of microorganisms when the basic requirements such as nutrients, moisture, oxygen, and appropriate temperature are present. The term ‘Antimicrobial’ refers to a broad range of technologies that can provide varying degrees of protection for textile products against microorganisms. We are now very conscious about our hygiene and cleanliness. Clothing and textile materials are not only the carriers of microorganisms such as pathogenic bacteria, odor generating bacteria and mold fungi, but also good media for the growth of the microorganisms. Anti-microbial finish is a recent innovation in finishes. The consumers are now increasingly aware of the hygienic life style and there is a necessity and expectation for a wide range of textile products finished with antimicrobial properties. This finish prevents the growth of bacteria and products finished in it have been proved environment friendly and health protecting, preventing diseases. It also prevents garments from unpleasant odor. Anti-microbial finish is a recent innovation in finishes. The consumers are now increasingly aware of the hygienic life style and there is a necessity and expectation for a wide range of textile products finished with antimicrobial properties. This finish prevents the growth of bacteria and products finished in it have been proved environment friendly and health protecting, preventing diseases. It also prevents garments from unpleasant odor. Growth of microbes on textiles can be observed in the early stages itself and can directly.

What are antimicrobials and antimicrobial finishes?

Antimicrobials that control, obliterate or stifle the development of various kinds of microorganisms and their adverse consequences of scent, staining and deterioration. Antimicrobials do not all work the same. By far most of antimicrobials work by leaching or moving from the surface on which they are applied. This is the mechanism used by leaching antimicrobials to poison a microorganism. Such chemicals have been used for decades in agricultural applications with mixed results. Other than influencing strength and valuable life, leaching technologies have the potential to cause a variety of other problems when used in garments. These include their negative effects because, they can contact the skin and potentially effect the normal skin bacteria, cross the skin barrier, and/or have the potential to cause rashes and other skin irritations. A more serious problem with leaching technologies has to do with their allowing for the adaptation of microorganisms. An antimicrobial with a completely different mode of action than the leaching technologies is a molecularly bonded unconventional technology. The bound unconventional antimicrobial technology, an organo-functional silane, has a mode of action that relies on the technology remaining affixed to the substrate killing microorganisms as they contact the surface to which it is applied. Effective levels of this technology do not leach or diminish over time. When applied, the technology actually polymerizes with the substrate making the surface

What Are Microbes? How micro-organism works?

Microbes are the smallest creatures that are not seen by the unaided eye. They include a selection of micro-organisms like Bacteria, Fungi, Algae and viruses. Bacteria are uni-cellular organisms which grow very rapidly under warmth and moisture. Further, sub divisions in the bacteria family are Gram positive (Staphylococcus aureus), Gram negative (E-Coli), spore bearing or non-spore bearing type. Some specific types of bacteria are pathogenic and cause cross infection. Fungi, molds or mildew are complex organisms with slow growth rate. They stain the fabric and deteriorate the performance properties of the fabrics. Fungi are active at a pH level of 6.5. Algae are typical microorganisms which are either fungal or bacterial. Algae require continuous sources of water and sun light to grow and develop darker stains on the fabrics. Cotton is biologically degraded by several microorganisms. Micro-organisms do not directly attack the substrate upon which they live. They are able to manufacture very complex non-living molecules called ‘enzymes’ which have the power to break down cellulose. These enzymes are solubilizing biocatalysts, proteinaceous, and highly specific. They enable complicated chemical reactions to occur under mild conditions even though the amount present at any time may be very small, for example, 0.001 to 0.01% on the weight of the substrate. Cellulolytic enzymes are not produced on the cellulose on the absence of cellulose. These enzymes are locally absorbed on the cellulose chains and it is proposed that different steps of degradation may occur.

Fig 1 how cessuose bond is broken
How cellulose bond is broken by Microorganism


Figure 1 shows how cellulose is broken down under the influence of an enzyme. The diagram illustrates cleavage of a “glycosidic” bond in cellulose (a polymer of glucose) by reaction with a molecule of water. This hydrolysis, the fundamental step in the biodegradation of cellulose, which would otherwise be immeasurably slow, is accelerated by the presence of an “enzyme”, or biocatalyst. The insoluble polymer is converted into soluble sugars which can then be metabolized inside the bacterial or fungal cells.

Factors Affecting the Growth of Microorganism in Fabric

Storage temperature, pH, Relative Humidity of environment, Moisture content, Laundering are the most important controlling factors in case of fabric storage to avoid the growth of microorganisms. Microorganisms grow over a very wide range of temperatures (250c – 300c). The quantity of the textile product must be taken into account in selecting a storage temperature at refrigerator temperature or below. The relative Humidity (RH) of the storage environment is also an important parameter to maintain. Fabric that undergoes surface spoilage from molds, yeast and certain bacteria should be stored under conditions of low RH. It is now generally accepted that the water requirements of microorganisms should be defined in terms of water activity. Laundering also causes little observable surface damage to cotton fiber but it is observed that damage to cotton fiber by microbial attack increases with each laundering. Severe damage is noticed after 10th laundering, suggesting that possible physical breakdown may make the fibers more accessible to microbial attack.


Sources of microbes

Whilst a few microorganisms are useful, others are dangerous and purpose disease. Disease-causing microorganisms spread to aquatic wildlife and vegetation and possibly even to people. Microorganisms also can reduce the amount of oxygen in the water, thereby hindering the water’s capacity to aid aquatic animal and plant life Microorganisms, together with bacteria, viruses and parasites, can come from in the air we breathe, in the soil, in our skin and bodies, improperly handled sewage, runoff from animal wastes, industrial sources including slaughter houses, meals and paper processing vegetation, and a few landfills and etc.


Necessity of antimicrobial finishing or Benefits of antimicrobial finish

  1. Preventing cross infection by microorganism
  2. Reducing the formation of odor created by microbes
  3. for safeguard of apparel and textile products from staining, discoloration and quality deterioration
  4. Make the durability better for the fabric by controlling growth of microbes
  5. Stops skin diseases
  6. Provides freshness to the fabrics.


Why and which types of apparels need antimicrobial finishing?

The inherent properties of the textile fibers provide room for the growth of microorganisms. Besides, the chemical processes may induce the growth of microbes. Humid and warm environment still aggravate the problem. Apparels like undergarments, socks, sportswear, medical bedding mattresses and covers need antimicrobial finish. Again, the consumers are now increasingly aware of the hygienic life styles and there is a necessity for a wide range of apparel products finished with advanced technological antimicrobial finishes.

Techniques of antimicrobial Treatment

The following three methods are applied for the treatment of cellulosic textile materials:

  1. Physical barrier
  2. The addition of toxic substances
  3. Chemical modification


Physical Barrier

Microbial growth requires contact between bacteria and fiber. Though micro encapsulation is not a chemical finishing process, it is a physicochemical method where a substrate reservoir of antimicrobial compound is placed between two layers of protective plastic. Coating materials such as paraffin, rubber etc. have been used with cotton yarns, netting, ropes, canvas etc. as a rot proofing agent.


Addition of toxic substance

Toxic inhibitors can be applied to the fibers, slivers, yarns or fabrics during sizing, dyeing or other stages of manufacturing to obtain resistance to microbial attack. Most popular inorganic inhibitors are compounds of copper, such as; cuprammonium hydroxide, carbonate and chloride. Phenolic compounds were the most popular mildew proofing agents in the past. Pentachloro phenol is the most widely used compound as mildew and rot proofing. Their use is restricted as these toxic inhibitors are harmful for skin.

Chemical modification: Chemical modification of cellulosic materials through.

  1. Acetylation

This is the earliest procedure for protecting cotton fibers from micro-organisms. The degree of resistance depends on amount of acetylation.

Cell-OH + CH3CO-O-OCCH3   —>  Cell-O-COCH3

  1. Phosphorylation

This treatment involves the reaction of cellulose with H3PO4 solution followed by drying and curing at temperature of 150-200 °C. The phosphate ester of cellulose thus produced has good flame and mildew resistance properties.


It involves the introduction of cyanoethyl group to cellulose by an ether linkage. It occurs as below

Cell-OH + CH2=CH-CN —–> Cell-O-CH2-CH2-CN

Only one –OH blocking provides good resistance to micro-organisms. Two outstanding advantages are good resistance to heat, good resistance to rotting. Cotton fiber can be protected from microbial degradation by treatment with formaldehyde as below

Cell-OH + H-CHO —-> Cell-O-CH2-O-Cell


 Other techniques of AM finishes

  1. Treating with AM finishes coating on apparel surface.
  2. Cross linking on apparel surface during printing or any other processes.
  3. Micro encapsulation of the antimicrobial agents with the fiber matrix.
  4. Regenerable N-halamine : N-Helamine are alternate methods for textiles functional finishing employ renewable antimicrobial agents. Another approach is using peroxydic moieties, such as peroxide and peroxyacids, which have been widely used disinfectants in the food and beverage industries as well as bleaching agents for textiles and paper. As for their mode of action, peroxydic compounds attack the microbe cell membrane, get into the cytoplasm and affect the microorganism enzymes.
  5. Development of Cost-Effective Menstrual Absorbent Pad with Eco-Friendly Antimicrobial Finish: Fabrics were first treated with Tulshi and Aloe Vera extract solution. Methanol extracts of the herb were directly applied on non-woven fabric by pad-dry cure method.
  6. PHMB: It is a hetro-disperse mixture of polyhexamethylenebiguanides with an average molecular weight ofapproximately 2500 Da. These are known as powerful biocides active against wide variety of bacteria, fungi, allege and viruses. Being a potent and broad spectrum bactericidal with low toxicity (MIC=0.5-10 ppm), it has been used as a disinfectant in the food industry and in the sanitization of swimming pools and is being used as a biocide in mouthwashes and wound dressing8. Due to good absorption onto cellulosic fiber, PHMB is used as germicides wound dressing and hygienic wipes and as an antimicrobial agent for textile as well. Poly hexamide treated cotton fabrics have been reported to maintained bactericidal properties for 10-15 laundry cycles.
  7. Quaternary ammonium compounds: seem attractive because their target is primarily the microbial membrane and they accumulate in the cell driven by the membrane potential. These compounds, particularly those containing chains of 12-18 carbon atoms, have been widely used as disinfectants. They carry a positive charge at the N atom in solution and inflict a variety of detrimental effects on microbes, including damage to cell membranes, denaturation of proteins and disruption of the cell structure. showed that, a novel quaternary ammonium salt, which contains both perfluoroalkyl group and diallyl groups, should be suitable a finishing agent for providing the fabrics with barriers against microorganisms, water, oil, soil and blood. Moreover, the introduction of diallyl groups.
  8. Miscellaneous: Besides the above agents, chemical modification of cellulosic materials through acetylation, phosphorylation and reaction with formaldehyde, cyanoethylation can be applied to receive the resistance to degradation against the cellulolytic microorganisms.
  9. Use of graft polymers, homo polymers and/or co polymerization on to the fiber.


Benefits of Antimicrobial Textiles

A huge variety textile product is now to be had for the benefit of the consumer. At first, the essential goal of the completion was to shield materials from being influenced by microorganisms especially parasites. Garbs, tents, guard materials and specialized materials, for example, geotextiles have hence completely been done utilizing antimicrobial specialists. Afterward, the home materials, for example, window ornaments covers, and shower mats accompanied antimicrobial completion. The use of the completion is currently reached out to materials utilized for outside, medical services area, sports and recreation. Novel technologies in antimicrobial finishing are successfully employed in non-woven sector especially in medical textiles. Textile fibers with built-in antimicrobial properties will also serve the purpose alone or in blends with other fibers. Bioactive fiber is a modified form of the finish, which includes chemotherapeutics in their structure such as synthetic drugs of bactericidal and fungicidal qualities. These fibers are not only used in medicine and health prophylaxis applications but also for manufacturing textile products of daily use and technical textiles. The field of application of the bioactive fibers includes sanitary materials, dressing materials, surgical threads, materials for filtration of gases and liquids, air conditioning and ventilation, constructional materials, special materials for food industry, pharmaceutical industry, footwear industry, clothing industry, automotive industry etc.


 Textile Products Used in Medical Sector

Medical textiles are manufactured items which consist of textile stuff used in hygiene, well-being and personal care, as well as surgical end uses. In other words, the medical textiles marketplace is a large, as a substitute complicated and extraordinarily various sector of the technical textiles and nonwovens industry. It’s comprised of numerous product categories, segments, sub-segments and sub-sub-segments. Products encompass a variety of different shapes, sizes and configurations. Any textile structure which has been designed and produced for the uses of medical applications, including implantable applications is to be called medical textile. The engineering method to expand textile products with a view to be suitable for scientific and surgical possess have to possess a combination of the properties inclusive of energy, flexibility, antimicrobial and moisture and air permeability. The current uses of textiles in Bangladesh may broadly be classified into two groups. One is Non-plantable materials and the other is health and hygiene products. Non-plantable materials are used for external application on the body and may or may not make contact with skin. Some examples of this kind of products are Wound care products, Bandages, Gauze, Lint/Cotton. Solving the problem of healthcare-associated infections and occupationally acquired infections involves an equation with many complex variables. One of the key components is healthcare workers (HCWs), such as doctors, nurses, laboratory personnel and technical professionals, who are frequently exposed to blood and body fluids. These fluids can transmit bacteria that cause colonization or infection, including multi-drug-resistant organisms (MDROs) such as Acinetobacter spp. and Enterobacteriaceae (Escherichia coli, Klebsiella pneumoniae). There is also a risk of transmission of viruses, including noroviruses, respiratory viruses and bloodborne viruses (human immunodeficiency virus, hepatitis B and C viruses), that can survive for hours or days on surfaces.


1.2 The applications of antimicrobial copper

One of the main applications of copper is in hospitals, although the use is not widespread. In the same study as above, researchers determined the germiest surfaces in a hospital room, bed rails, call buttons, chair arms, tray table, data input, and IV pole and replaced them with copper components. The results were very promising. Compared to the rooms made with traditional materials, there was an 83% reduction in bacterial load on the surfaces in the rooms with copper components. Additionally, infection rates of patients were reduced by 58%. Technically, you can use copper at home. However, according to Johnson, the majority of copper products for the home have a treatment on it to prevent the oxidation that causes the beautiful original color of the copper to turn to a greenish-blue over time. This treatment prevents you from getting the beneficial antimicrobial properties of copper. That being said, copper still has the ability to be toxic to bacteria when it’s at this oxidized greenish state, however, according to Johnson, scientists still don’t know exactly how this mechanism works. According to current research, the downside of using copper is that it isn’t as effective at destroying viruses as it is at killing bacteria – particularly if it’s an airborne virus. Much of this has to do with the fact that viruses are technically not living organisms they are infection agents, which are not alive like cells are, and as such they are more durable. Viruses are different in that they are not cells but rather infect healthy cells that allows them to replicate. The virus can come in direct contact with the upper respiratory tract and eyes and enter healthy cells, so a copper strategy would be largely ineffective says Bilsky. Another downside is that there are some unsubstantiated claims that may mislead people. Some companies try to market copper jewelry or copper-infused socks as antimicrobial protection for the wearer, but these are ineffective. Hopefully, more research will continue to be conducted so we can better understand the antimicrobial properties of copper and the most effective ways to use it in everyday life to keep us healthy.


Materials and Methods: Knit Fabric, Copper sulfate, Ascorbic acid, Bio-quart 200A, Poly ethylene Glycol , NaOH ,Soda ash ,Wetting agent, Sequestering agent, Detergent, Hydrogen Peroxide, Bezaktiv Red S-2B , Bezaktiv Yellow 3-R 150, Bezaktiv Blue S-RN.


Source of Fabric and chemical Collection:

  • Fabrics from Pakiza Knit Composite Ltd.
  • Chemicals from DYSIN-CHEM LIMITED
  • Dyes from R.H.CORPORATION


Description of the Samples:


Table 1: Description of Samples
Sample Name. Description Dyeing % Finishing
A 100% Cotton ,Knit fabric (s/j), 160 GSM,

30s Combed.

Bezaktiv Red S-2B,(1%) Bezaktiv Yellow3-R150 (1%), Bezaktiv Blue S-RN (0.5%). N/A
B 100% Cotton ,Knit fabric (s/j), 160 GSM,

30s Combed.

Bezaktiv Red S-2B,(1%) Bezaktiv Yellow3-R150 (1%), Bezaktiv Blue S-RN (0.5%). Copper Finished


Sample Preparation Procedure

Process Flow Chart of Sample Preparation

Figure 2: Process Flow Chart of Sample Preparation.


Samples are scoured by using 5gm/L Alkali (NaOH), 3 gm/L Soda ash to adjust PH (PH required for scouring is 10.5) and 1 gm/L Wetting agent, Sequestering agent and Detergent. IR Lab Dyeing Machine was used scouring at 90 degree Celsius for 1 hour.


Samples are bleached by using 5gm/L Sodium silicate, 0.5 gm/L NaOH and 1.8 gm/L Na2CO3, 4.5 gm/L H2O2 (35%) as well as 1 gm/L Wetting agent, sequestering agent and Detergent.IR Lab Dyeing Machine was used for Bleaching  at 90 degree Celsius for 1 hour.


Dyeing has done under the given parameters in IR LAB DYEING MACHINE:

Table 2: Dyeing Parameters
SL Process Parameter Unit Amount Stock solution
01 Levelling Agent gm/L 1
02 Bezaktiv Red S-2B, Bezaktiv Yellow 3-R 150, Bezaktiv Blue S-RN. % 1%,1%,0.5% 1%
03 Glauber Salt gm/L 40
04 Soda Ash gm/L 10
05 Sample Weight gm 5
06 M:L 1:15
07 Temperature Degree Celsius 90
08 Time Min 60


2.3.3 Nano particle formation:

Copper nanoparticles can be applied to fabric quickly and easily, from an aqueous suspension, using a small paintbrush. The solution can be made in any glass container, such as a jar, with common chemicals that are safe to use anywhere.


  1. Filled one glass container with 100 mL of water.
  2. Dissolved the copper sulfate in the box stirred until all the solids are dissolved this could take numerous minutes.
  3. Filled the other container with 100 mL of hot water.
  4. Dissolved the ascorbic acid in the hot water stirred until all dissolved this may also take several minutes and reheated the solution afterwards.
  5. Poured the hot ascorbic acid solution into the container of copper sulfate solution and stirred the solution that immediately turned into a dark greenish brown color.
  6. After a few moments metallic copper began to precipitate out of solution and settle at the bottom which has a salmon color.
  7. Continued stirring until all of the copper precipitates out the solution became lighter eventually turned into emerald green while the layer of copper became thicker.
  8. Allowed all the copper particles to settle to the bottom of the container, then slowly decant off the green liquid layer.
  9. covered the copper particles with a layer of distilled water to prevent the copper from oxidizing in the air, particles are ready to apply.

Fig 3: Freshly Prepared Copper (II) Particles with mother solution

Fig 4:  Copper (II) Particles without solution.


Final Sample Preparation: Using 15% copper Nano particles the samples are finished at 60-degree Celsius temperature at 1:15 ration for 20 minutes.


Final Sample Preparation
Final Sample Preparation                                                                                                                

Test procedure for Antimicrobial Finishing

The fabric sample was cut into small pieces (1 sq. Inch) in aseptic condition and kept them in the sterilized conical flask containing 100 ml of sterilized water. The conical flask was kept at room temperature for 48 hours for the diffusion of antimicrobial agent to the water. The known microbial samples were prepared with normal saline and diluted for the microbial counts. The same dilution was also used for the challenge test. Diffused solution from fabrics was then used as samples for the potency test. 100 ml of microbial sample (known microbial counts) of diffused was then separated on to the agar medium and 100 ml of diffused fabric solution as a challenge was added to find out the antimicrobial potency which had been added in the supplied fabric samples.


Testing methods for Antimicrobial Finishing:


The AATCC Test Method 147 is a qualitative antimicrobial test used to detect bacteriostatic activity on textile materials. This antimicrobial testing method is useful for obtaining a rough estimate of activity by the size of the zone of inhibition and the narrowing of the streaks caused by the presence of the antimicrobial agent permitting an estimate of the residual antimicrobial activity after multiple washings. In this method the agar surface is covered by thin strips of fabric which is to be tested and previously inoculated. In this method the inhabitation zones are quantitively defined after the incubation. This method is quick and easily executed but nonrealistic and non-reproducible. The AATCC 147 is a Qualitative test used to detect bacteriostatic activity on textile materials. The test Method determines antibacterial activity of diffusible antimicrobial agents on treated textile materials. The test is followed in the cases where the antibacterial agent is migratory i.e. diffusible through the agar. The size of the zone of inhibition and the narrowing of the streaks caused by the presence of the antibacterial agent permit an estimate of the residual antibacterial activity after multiple washings. Specimens of the test material, including corresponding untreated controls of the same material, are placed in intimate contact with growth agar which has been previously streaked with test organism. After incubation, a clear area of interrupted growth underneath and along the sides of the test material indicates antibacterial activity of the specimen. The AATCC 147 Test organism is Gram positive organism which is Staphylococcus aureus, ATCC No. 6538. Gram negative organism is Klebsiella pneumoniae, ATCC No. 4352. 5 to 7 days for commonly used organisms like mentioned in AATCC 147 test standard. The method is not suitable for materials which are not migratory and are unable to diffuse thru the bacterial growth medium.



The method is known as Antimicrobial Test Assessment of Antimicrobial Finishes on Textile Materials. This antimicrobial test is a quantitative method (AATCC 100) in which assessment of antibacterial finishes on textile materials (fabric finishes, etc.) is determined by the degree of antibacterial activity. In this method test and control fabrics are inoculated with suspension of microorganisms. Concentration is enumerated after a defined contact. Microbial growth is identified by the basis of differences between test and control fabrics. The method is realistic but time consuming.


ISO 20743

 The method is known as Textiles determination of antibacterial activity of antibacterial finished product.


The method is known as Antimicrobial Test Antifungal Activity – Antimicrobial Assessment on Textile Materials The two purposes of this antimicrobial test method (AATCC 30) are to determine the susceptibility of the textile materials to mildew and rot and to evaluate the antimicrobial efficacy of fungicides on textile materials.


The method is known as Antimicrobial Test New Carpet Materials -.Antimicrobial Testing This antimicrobial testing method (AATCC 174) is designed to determine the antimicrobial activity of new carpet materials.

JIS I 1902

The method is known as testing for antibacterial activity and efficiency on textile products. This a quantitive method. In this method fabric is inoculated in in liquid media with specific concentration of microbial suspension. After a certain contact period the microorganism are enumerated. This method is reproducible but very expensive as well as time consuming.


This method is known as standard test method for determining the antimicrobial activity or immobilized antimicrobial agents under dynamic contact conditions. This is a quantitive method .Test and control fabrics are placed individually in a liquid media where test microorganisms are also inoculated. Flasks are then shaken carefully. After the required contact period microbial concentration can be determined and reduction can be calculated.


Result and Discussion

Zeta Potential Analysis:

Zeta potential is a measurement based on the charges on the particles in a suspension or emulsion. A zeta potential analyzer does the measurements and calculations to ascertain the zeta potential of a given material. Zeta potential analyzers are used by the ceramics, electronic and pharmaceutical industries to determine the stability of their suspensions and emulsions. The higher the zeta potential, the more stability the product has. Applying an electric field and measuring the velocity of charged particles and using ultrasound waves to create motion and then measure the electric.


Staphylococcus aureus count

Staphylococcus aureus is the most perilous of the entirety of the numerous normal staphylococcal microscopic organisms. These gram-positive, sphere-shaped frequently cause skin diseases yet can cause pneumonia, heart valve contaminations, and bone diseases. Staphylococcus aureus testing was conveyed to notice the presence of puss shaping microbes. The sample was homogenously distributed on to the plate using a glass spreader in a backward and forward movement while rotating the plate and then the plates were incubated at 37°C for 24 hours. Figure shows the staphylococcus containing plate from which Staphylococcus aureus was counted.

E.coli count

  1. coli (Escherichia coli), is a type of bacteria that commonly lives for intestines. It’s also located in the gut of a few animals. Most forms of E. coli are innocent or even assist hold your digestive tract healthful. However some lines can motive diarrhea in case you consume infected meals or drink fouled water. . E. coli is determined by counting the number of yellow and yellow brown colonies growing on a 0.45 micron filter placed on m-TEC media and incubated at 35.0º C for 22-24 hours. The addition of urea substrate confirms that colonies are E. coli.

Salmonella enteridis count:

Salmonella is a genus of rod-shaped Gram-negative bacteria of the family Enterobacteriaceae. The two species of Salmonella are Salmonella enterica and Salmonella bongori. S. enterica is the type species and is further divided into six subspecies.Total Salmonella enteridis depend take a look at has been performed to discover the presence of lethal pathogenic bacteria. The Salmonellae can be transmitted by means of water, air, and food or greater in reality direct anal-oral transmission. Figure four shows the Shigella-Salmonellae containing plate from which Shigella-Salmonellae was counted. No Shigella-Salmonellae has been discovered from the samples of copper finished fabric.

Bacillus subtilis count:

Bacillus subtilis regarded additionally as the hay bacillus or grass bacillus, is a Gram positive catalase-high quality bacterium, determined in soil and the gastrointestinal tract of ruminants and people. Bacillus subtilis was conveyed to notice the presence of puss shaping microbes. The sample was homogenously distributed on to the plate using a glass spreader in a backward and forward movement while rotating the plate and then the plates were incubated at 37°C for 24 hours. Figure shows the Bacillus subtilis containing plate from which Bacillus subtilis was counted.

Antimicrobial Assessment on Normal Dyed Fabric:

Assessment of E.coli
Fig 8: Assessment of E.coli | Count on normal dyed sample. (Sample A)
Fig 9: Assessment of Salmonella enteridis Count on normal dyed sample. (Sample A)
Fig 9: Assessment of Salmonella enteridis Count on normal dyed sample. (Sample A)
Fig 10: Assessment of Staphylococcus aureus Count on normal dyed sample (Sample A)
Fig 10: Assessment of Staphylococcus aureus Count on normal dyed sample (Sample A)
Fig 11: Assessment of Bacillus subtilis Count on normal dyed sample. . (Sample A)
Fig 11: Assessment of Bacillus subtilis Count on normal dyed sample. . (Sample A)






Table 3:  Particulars of  Sample A

Name of the sample


Sample B1, Sample B2, Sample B3, Sample B4.

Type/particulars of the sample


Copper Finished

Test Parameter : Antimicrobial activity
Date of receipt : 03.03.2021
Date of analysis : 09.03.2021
Date of issue of the report : 14.03.2021
Name of the Institution : Atomic Energy Research Establishment (Bangladesh).


Table 4:  Antimicrobial Activity of Sample A
Sl. No. Name of the Product Organism used Zone of Inhibition

(Diameter in mm)




Sample A (Normal DYED)

Sample A

Bacillus subtilis 0.0
Staphylococcus aureus 0.0
E. coli 0.0
Salmonella enteridis 0.0


  Antimicrobial Assessment on Copper Finished Fabric

Fig 13 : Assessment of Salmonella enteridis count on copper particle finished sample.
Fig 13 : Assessment of Salmonella enteridis count on copper particle finished sample.
Fig 13 : Assessment of Salmonella enteridis count on copper particle finished sample.
Fig 13 : Assessment of Salmonella enteridis count on copper particle finished sample.


Fig 14: Assessment of Staphylococcus aureus Count on copper particle finished sample.
Fig 14: Assessment of Staphylococcus aureus
Count on copper particle finished sample.
Fig 15 Count on copper particle finished sample.
Fig 15
Count on copper particle finished sample.




Table 5: Particulars of Sample B

Name of the sample


Sample B1, Sample B2, Sample B3, Sample B4.

Type/particulars of the sample


Copper Finished

Test Parameter : Antimicrobial activity
Date of receipt : 03.03.2021
Date of analysis : 09.03.2021
Date of issue of the report : 14.03.2021
Name of the Institution : Atomic Energy Research Establishment (Bangladesh).


Table 6: Antimicrobial Activity of Sample B.
Sl. No. Name of the Product Organism used Zone of Inhibition

(Diameter in mm)

01 Samplen B(copper finished)


Bacillus subtilis 19.25
Staphylococcus aureus 15.5
E. coli 15.5
Salmonella enteridis 12.02


Where, diameter =  ((π × Area)/4)

In antimicrobial attachment zone of inhibition is used. A Zone of Inhibition Test, also called a Kirby-Bauer Test, is a qualitative method used clinically to measure antibiotic resistance and industrially to test the ability of solids and textiles to inhibit microbial growth. A bacterial or fungal strain of interest is grown in pure culture. Using a sterile swab, a suspension of the pure culture is spread evenly over the face of a sterile agar plate. [13] The antimicrobial agent is applied to the center of the agar plate (in a fashion such that the antimicrobial doesn’t spread out from the center). A hole can be bored in the center of an agar for a liquid substance. The agar plate is incubated for hours (or longer if necessary), at a temperature suitable for the test microorganism. If antimicrobial agent leaches from the object into the agar and then exerts a growth-inhibiting effect, then a clear zone (the zone of inhibition) appears around the test product. The size of the zone of inhibition is usually related to the level of antimicrobial activity present in the sample or product – a larger zone of inhibition usually means that the antimicrobial is more potent. Zone of inhibition testing is fast and inexpensive relative to other laboratory tests for antimicrobial activity. Zone of inhibition testing is especially well suited for determining (albeit qualitatively) the ability of water-soluble antimicrobials to inhibit the growth of microorganisms. A number of samples can be screened for antimicrobial properties quickly using this test method. A variety of antimicrobial product types can be tested using this method. Liquids, coated antimicrobial surfaces, and antimicrobial-impregnated solid products can all be tested for their ability to produce a zone of inhibition. Antimicrobial agents that leach out of the object and into the aqueous agar matrix, such as silver ions, usually show better results than antimicrobials that stay affixed to the object or textile or that are not water-soluble. Zone of Inhibition tests do not necessarily indicate that microorganisms have been killed by an antimicrobial product – just that they have been prevented from growing. Microbial growth agars themselves may interfere with the function of some antimicrobial agents. The method cannot be used to test the activity of antimicrobial agents against viruses, since viruses don’t “grow” on agar plates like bacteria (viruses don’t replicate outside of their host organisms).The method has some natural variability, and zones of microbial inhibition do not always have clear or regular boundaries.

The method is not classically quantitative (though sometimes the diameter of the zones of inhibition are measured and recorded)Researchers who develop antimicrobial textiles, surfaces, and liquids use this test as a quick and easy way to measure and compare levels of inhibitory activity. [14] With this method, approximately one million cells from a single strain are spread over an agar plate using a sterile swab, then incubated in the presence of the antimicrobial object (ex: an oxacillin disk, pictured below). If the bacterial or fungal strain is susceptible to the antimicrobial agent, then a zone of inhibition appears on the agar plate, such as on the agar plate on the left-hand side of the photo below. If it is resistant to the antimicrobial agent, then no zone is evident, such as on the agar plate on the right-hand side of the photo of upper fig 11-18. Zone of Inhibition Testing is a fast, qualitative means to measure the ability of an antimicrobial agent to inhibit the growth of microorganisms. In the world of antimicrobial substances/surfaces, the degree to which these materials are inhibitory can be of vital importance to the health of the consumer. This test is an outstanding qualitative way for manufacturers of antimicrobial surfaces/substances to be able to compare the inhibition levels of their products. Microchem Laboratory was built around antimicrobial innovation and antimicrobial research and development. If your company is interested in screening chemicals, products, or antimicrobial treatments for their ability to inhibit the growth of microorganisms, the zone of inhibition test may be a great place to start. The Kirby-Bauer test or the disc diffusion antibiotic sensitivity test is used to detect whether an antibiotic is effective to treat a given bacteria. The test sample is usually collected from any patient who is known to have been infected. A small part of the collected sample is applied uniformly on a petri-dish. A piece of filter paper impregnated with a few different antibiotics applied at different places, is then placed on the dish. This setup is finally placed in agar. The antibiotic diffuses into agar after which it’s concentration.

Antimicrobial activity comparison
Fig 16: Antimicrobial activity comparison


Copper finished fabric has shown goon zone of inhibition in antimicrobial test, whereas normal dyed fabric has shown no zone of inhibition

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