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PubMed1999

Antimicrobial effectiveness of 2% glutaraldehyde versus other disinfectants for hospital equipment, in an in vitro test based on germ-carriers with a high microbial contamination.

2% glutaraldehyde is the reference disinfectant for hospital instruments. However, its high environmental toxicity makes desirable to search for alternatives. We compare the antimicrobial activity of 2% glutaraldehyde with 0.44% N-duopropenide (NDP), 0.66% NDP in 48 degrees alcoholic solution (NDP-alc), 0.13% glutaraldehyde-phenate, 1% or 3% persulphate (Virkon) and 0.1% or 0.5% chlorhexidine, using a model that mimics non-regular surface instruments contaminated with microbial strains (44 bacteria, 6 of which were Mycobacterium). The contaminated carrier is soaked in the disinfectant solution. After 5 or 20 minutes contact the disinfectant is neutralized. The overall results on all microorganisms in 20 minutes, show similar antibacterial activity for 2% glutaraldehyde and 0.66% NDP-alc, followed by 0.44% NDP and after by the two concentrations of Virkon and 0.5% chlorhexidine. The 0.13% glutaraldehyde-phenate and 0.1% chlorhexidine exhibited significantly less effect than any other disinfectant. 0.66% NDP-alc was faster antimicrobial activity than 2% glutaraldehyde, destroying totally the inoculum in 5 minutes. Activity on Mycobacterium showed great differences between 2% glutaraldehyde and the rest of products (> 5 log versus < 3 log reduction in 20 minutes), with an exception: NDP-alc, with similar and faster activity (> 5 log in 5 minutes) than 2% glutaraldehyde. With human blood, the survival microorganisms increase 0.3 log (average) in all the disinfectants used. The aggressiveness on metallic devices was greater in Virkon than in the other disinfectants. We conclude that NDP (alone or in alcoholic solution) may be a good alternative to glutaraldehyde in hospital instruments disinfection.

Aldehydes↗
PubMed2001

[Microbiological evaluation of two different disinfection protocols of a new hemodialysis monitor with an ultrafilter].

BACKGROUND: Hemodialysis monitors represent a frequent site for bacterial contamination. METHODS: Two different disinfection protocols on a new device (Formula(R), Bellco) have been compared: only chemical or chemical plus heat disinfection by means of CFU, and LAL test. The endotoxin removing capacity of ultrafilter was tested with varying lipopolysaccharide concentrations. RESULTS: Similar results were obtained with heat disinfection compared to chemical disinfection (CFU and LAL test). The LAL test (chromogenic and gel-clot) showed that the ultrafilter performance decreased with use and was significant after 200 operating hours. CONCLUSIONS: Heat disinfection between dialysis shifts and chemical disinfection at the end of the day exclude bacterial contamination of the monitor as well as chemical disinfection; LAL test is a useful and simple tool to assess the ultrafilters performance in each Center.

Bacterial Infections↗
PubMed2001

Synergistic effect of solar radiation and solar heating to disinfect drinking water sources.

Waterborne diseases are still common in developing countries as drinking water sources are contaminated and feasible means to reliably treat and disinfect these waters are not available. Many of these developing countries are in the tropical regions of the world where sunlight is plentiful. The objective of this study was to evaluate the effectiveness of combining solar radiation and solar heating to disinfect contaminated water using a modified Family Sol*Saver System (FSP). The non-UV transmittable cover sheet of the former FSP system was replaced with an UV transmittable plastic cover sheet to enable more wavelengths of sunlight to treat the water. Disinfection efficiency of both systems was evaluated based on reduction of the natural populations of faecal coliform, E. coli, enterococci, C. perfringens, total heterotrophic bacteria, hydrogen sulphide producing bacteria and FRNA virus. The results showed that under sunny and partly sunny conditions, water was heated to critical temperature (60 degrees C) in both the FSP systems inactivating more than 3 log (99.9%) of the concentrations of faecal coliform and E. coli to undetectable levels of < 1 CFU/100 mL within 2-5 h exposure to sunlight. However, under cloudy conditions, the two FSP systems did not reduce the concentrations of faecal indicator bacteria to levels of < 1 CFU/100 mL. Nonetheless, sufficient evidence was obtained to show that UV radiation of sunlight plus heat worked synergistically to enhance the inactivation of faecal indicator bacteria. The relative log removal of indicator microorganism in the FSP treated water was total heterotrophic bacteria < C. perfringens < F RNA virus < enterococci < E. coli < faecal coliform. In summary, time of exposure to heat and radiation effects of sunlight were important in disinfecting water by solar units. The data indicated that direct radiation of sunlight worked synergistically with solar heating of the water to disinfect the water. Thus, effective disinfection was observed even when the water temperature did not reach 60 degrees C. Finally, the hydrogen sulphide test is a simple and reliable test that householders can use to determine whether their water had been sufficiently disinfected.

Biomarkers↗
PubMed2003

Effects of different disinfectants on decontamination of laryngoscopes.

Guidelines for controlling possible contamination of laryngoscopes should be formulated with the benefit of relevant experimental data. In this study, the effects of five different disinfectants commonly used for the disinfection of laryngoscopes are evaluated. We formed 14 groups, with 10 blades in each. The first 7 groups were contaminated with hospital related meticillin resistant Staphylococcus aureus (MRSA), and the remaining 7 groups with hospital related multiple resistant Pseudomonas aeruginosa (PA). For the first group of blades, no disinfection procedure was carried out and, were assumed as a control group. Blades in remaining groups were rested for 10 minutes in containers containing 70% alcohol (II), 1/100 dilution of cetrimide (III), 1/100 dilution of chlorhexidine (IV), 1/10 dilution of chlorhexidine (V), 1/10 dilution of povidone iodine (VI), and 1/100 dilution of ammonium chloride (VII). Disinfectant used in a group was considered effective when growth was seen in 5 or less than 5 plates representing that group. All disenfectants tested were found effective on decontamination of laryngoscopes. Five different moderate level disinfectants, which are commonly used for the disinfection of laryngoscopes, have been found effective even on resistant hospital microorganisms like MRSA and P. aeruginosa. They may be the choices of the disinfectants, especially 1/10 dilution of chlorhexidine gluconate and 1/100 dilution of ammonium chloride.

Decontamination↗
PubMed2004

Evaluation of electrochemically generated ozone for the disinfection of water and wastewater.

Effective wastewater treatment is critical to public health and well-being. This is especially true in developing countries, where disinfection of wastewater is frequently inadequate. People who live in these areas may benefit from wastewater disinfection using ozone. This study evaluated the ability of a new electrochemical process of ozone generation, which produced ozone continuously at high pressure and concentration by the electrolysis of water, to disinfect tap water and secondarily treated wastewater. Inactivation of Klebsiella terrigena, Escherichia coli, MS2 bacteriophage and poliovirus 1 was evaluated first in reverse osmosis (RO) treated water. Inactivation of K. terrigena (6-log), E. coli (6-log), MS2 (6-log) and poliovirus 1 (>3-log) was observed after 1 min of ozonation in a 1 L batch reactor. Experiments were then performed to assess the microbiological impact of disinfection using ozone on secondarily treated municipal wastewater. The effect of ozonation on wastewater was determined for total and faecal coliforms, bacteriophages and heterotrophic plate count (HPC) bacteria. Electrochemical ozone generators provided an effective, rapid and low-cost method of wastewater disinfection. Based on the results of this research, electrochemically generated ozone would be well suited to remote, small-scale, disinfection operations and may provide a feasible means of wastewater disinfection in developing countries.

Developing Countries↗
PubMedDate not supplied

Influence of disinfectants on dentin bond strength of different adhesive systems.

The influence of water disinfectants used in dental unit waterlines on the dentin bonding of different adhesive systems was investigated by using push-out tests. Three hundred and twenty dentin disc specimens were prepared from caries-free human molars. In each specimen, a standardized conical cavity was prepared while cooling with water from a dental unit containing one of three different disinfectants (n=80 each group; A=control: water without disinfectant, B: Alpron neutral, C: Alpron mint, D: Dentosept P). Subsequent rinsing of the cavities was performed With the respective disinfectant. The cavities were filled with the following combinations of dentin adhesives and composites, resulting in 16 subgroups (n=20): Syntac Classic/Tetric Ceram, Clearfil Liner Bond 2V/Luxacore, OptiBond FL/Prodigy and Prime&Bond NT/Spectrum. After polishing the fillings, one half of each subgroup (n=10) was stored in water (37 degrees C) for 24 hours. The other half was stored in water (37 degrees C) for 180 days and additionally thermocycled (2000 cycles at 5/55 degrees C). The bond strength was then measured by push-out tests. Statistical analysis of the data was carried out using ANOVA and pairwise t-tests (Significance level p < or = 0.01). The disinfectants showed no significant influence on the loads required for debonding of Syntac Classic/Tetric Ceram, Clearfil Liner Bond 2V/Luxacore and OptiBond FL/Prodigy as compared to the controls. However, the use of disinfectants in the water supply of a dental unit decreased dentin bond strength in the specimens filled with Prime&Bond NT/Spectrum. Disinfectants in the water of dental unit waterlines may have an influence on dentin bonding, depending on the adhesive system used.

Amines↗
PubMedDate not supplied

The persistence of microorganisms on impression materials following disinfection.

Following in vitro inoculation with C albicans or P aeruginosa, three impression materials--polysulfide rubber, irreversible hydrocolloid, and poly(vinyl siloxane)--were disinfected with either 0.1% or 0.02% chlorhexidine gluconate and a quantitative assessment of the microorganisms was made. Very few microorganisms were retained on the poly(vinyl siloxane) material immediately after microbial inoculation. The numbers of microorganisms on polysulfide impression materials diminished rapidly with time even without disinfection, and a 30-minute disinfection procedure resulted in total microbe elimination. With irreversible hydrocolloid, microorganisms persisted and disinfection procedures were considerably less effective. When the disinfection efficacy of three commercially available agents was compared using irreversible hydrocolloid impression material, chlorhexidine gluconate (0.2%) was found to be less effective than either glutaraldehyde (2%) or sodium hypochlorite (0.0125%); the latter two agents were comparable in their antimicrobial effect. Thus, a simple disinfection regime of 30 minutes with commonly available disinfectants may be effective in eliminating cross-contamination from impression materials.

Anti-Infective Agents, Local↗
PubMed1990

On the methods of disinfecting bronchofibroscopes.

An apparatus is proposed for the wet disinfection of bronchofibroscopes which enables to wash with disinfectant solution the external surfaces of the tube and instrument channel while keeping dry the control mechanism. Several disinfecting regimens have been tested using chlorohexidine (Gibitan), benzalkonium chloride (Roccal), diocide and ethanol solutions. On experimental contamination of bronchofibroscopes with a P. aeruginosa culture effective disinfection was achieved using 0.5% aqueous and ethanol solution of chlorohexidine and 1% benzalkonium chloride solution (5-min, exposure in the circulation mode of the apparatus), 0.1% solution of diocide only produced a bactericidal effect after a 30-min, exposure. Adequate disinfection was not feasible when the endoscope was soaked in disinfectant. Similar results were obtained when bronchofibroscopes were disinfected in a clinical setup where they became contaminated with the most common pathogenic and potentially pathogenic microflora from the airways of patients suffering from purulent pulmonary diseases.

Benzalkonium Compounds↗
PubMed1989

[Problems in disinfection of dental impression materials].

In view of the risk of infection of the dentist and his staff in the dental surgery and dental laboratory and also of the patient with regard to hepatitis B and potentially also of AIDS, interruption of possible chains of infection by means of specific disinfection measures is to be demanded. Whereas appropriate hygiene concepts exist for disinfection of instruments, surfaces of equipment and furniture with regard to selection and application of various methods which may be considered, there are still extensive deficits for the domain of impression materials and their possible decontamination. In this regard, dentists frequently lack information with an adequate scientific basis that is understandable and oriented to practical requirements. Owing to the diversity of materials and their different behavior (cf. Tab. 1), appropriate recommendations can only be made on the basis of extensive studies. We assume that a practically relevant procedure must meet the following requirements: 1) sufficiently high rates of bacterial reduction in accordance with the guidelines of the DGHM, 2) lack of alterations in the dimensions or surfaces of the materials, 3) universal applicability, 4) practicability within a time period which is acceptable for smooth operation of the practice, 5) can be employed without problems for the staff. The object of the report are bacteriological results and materials testing data for the application of various methods of disinfection to selected impression materials. To summarize, it can be stated with regard to the bacteriological results that disinfection of impression materials is possible with fulfillment of the criteria specified above, but that there is a pronounced dependence of the results on the product formulation of the disinfectant and also of the impression material (cf. Fig. 4 and 5). Investigations of the material-related effects of the disinfection measures showed that extrapolation of the findings from one group of materials to another is also not possible in this connection, and that moreover the materials used to produce the model must also be included besides the impression materials used (cf. Fig. 9). Accordingly, statements on the suitability of a disinfection procedure are present admissible at most for the respective combination of materials tested, which makes practical introduction problematical.

Bacteria↗
PubMed1978

[Hydrogen peroxide, chloramine T and chlorhexidrine in the disinfection of acrylic resin].

The effectiveness of 3% h drogen peroxide, 5% chloramine T and 0,5% chlorhexidine gluconate solutions in disinfection of acrylic resine plates massively infected with oral flora was analysed. The acrylic resine plates used for investigations, were infected in vitro with mixed salivary flora characterized by small numbers of yeast-like fungi (1st group), or great number of these microorganisms (2nd group). Infected plates were exposed to solutions of analysed disinfectants during various time periods. After rinsing or inactivation of disinfectant residues, acrylic plates were put into bacteriological medium and incubated during 7 days period in 37 degrees C. The results of this study indicated the effectiveness of acrylic plates disinfection to be dependent on used disinfectant, time of exposition, and microorganisms present on the surface of acrylic resine. The solutions of disinfectants were less active in the cases of plates infected with material containing great numbers of yeast-like microorganisms. Among analysed disinfectants 0,5% solution of chlorhexidine was characterized by most effective and rapid activity, whereas 3% solution of hydrogen peroxide was found to be the least effective.

Acrylic Resins↗
PubMed1986

Antibacterial activity of dilute povidone-iodine solutions used for ocular surface disinfection in dogs.

Bacterial cultures of specimens from healthy canine eyelids and ocular surfaces were found to demonstrate bacterial growth in 69.7% (53/76) of the eyes sampled. Organisms most commonly isolated included: Staphylococcus aureus, alpha-hemolytic Streptococcus sp, S epidermidis, and Escherichia coli. Evaluation of dilute povidone-iodine solutions for effectiveness as ocular surface disinfectants was conducted. Bacterial growth initially detected in 32 of 46 eyes was not detected after disinfection with a 2-minute scrub and 2-minute soaking procedure, using 1:2, 1:10, or 1:50 dilutions of a povidone-iodine solution that contained 1% available iodine. The eyelid and ocular surfaces of 16 eyes were disinfected with 1:100 povidone-iodine solution. Bacterial growth initially present in 10 of 16 eyes was present in 1 eye after disinfection and consisted of a single colony of E coli. After eyes were disinfected with 1:10, 1:50, or 1:100 povidone-iodine solutions, there was no evidence of corneal epithelial edema or sloughing. In 15 eyes subjected to disinfection with the 1:2 dilution, one instance of epithelial corneal edema was noticed. A 1:50 dilution of povidone-iodine is recommended as an ocular surface disinfectant for use in presurgical situations.

Animals↗
PubMedDate not supplied

[Analysis of the use of disinfectants in Italy particularly in Southern Italy].

In an investigation of the use of disinfectants in hospitals, the replies received from 338 institutions were analysed and subsequently compared with those obtained from southern Italy. It was found that benzalkonium chloride was the substance most widely used in Italy for disinfection of the surgical field, wounds, excoriations, sores, the skin prior to injections, surgical instruments, medical apparatus, catheters, thermometers and sanitary appliances, whereas chlorhexidine was preferred for disinfection of the hands, and for ambient surfaces in combination with cetrimide. Formic aldehyde was preferred for ambient surfaces, the air of confined spaces, and, in conjunction with chlorine and its derivatives, for sanitary services and their vessels. Glutaraldehyde was the substance most commonly employed for the disinfection of medical apparatus fitted with optic fibre lenses. In southern Italy, by contrast with the position in Italy as a whole, there was a greater use of chlorine and its derivatives for the disinfection of ambient surfaces, benzalkonium chloride for the disinfection and cleaning of sanitary services, vessels, and equipment with optic fibres, and alcohols for the disinfection of surgical instruments and sanitary appliances.

Disinfectants↗
PubMed1995

A comparative study of the microbiologic effectiveness of chemical disinfectants and peroxide-neutralizer systems.

We evaluated the antimicrobial activity of chemical and hydrogen peroxide-neutralizer contact lens disinfection systems. The acute activity, storage, and recontamination potential of the two disinfection methods were compared by challenging the disinfectants with Staphylococcus spp., Pseudomonas aeruginosa, Serratia marcescens, Candida spp., and Aspergillus fumigatus. Chemical disinfectants preserved with polyquaternium-1 and polyhexamethylene biguanide and hydrogen peroxide-neutralizer systems with no additional preservatives were tested. Additionally, lens cases from patients using both systems were evaluated. Lens cases from patients using peroxide-neutralizer systems tended toward heavier contamination (31.8%) than the cases disinfected with a chemical system (20.3%, P = 0.16). The laboratory results showed that the differences in activity of chemical and peroxide-neutralizer systems was not statistically significant at the disinfection times against Staphylococcus epidermidis, S. marcescens, Candida parapsilosis, and A. fumigatus (P = 0.1037 to P = 0.5412). A statistical difference was shown against C. albicans (P = 0.0176) in favor of the peroxide-neutralizer systems. The reverse was true during storage. Although the chemical disinfectants maintained the population of microorganisms, the bacteria and yeast increased to over 10(7) CFU/mL in neutralized peroxide systems. Overall, the results emphasize the importance of contact lens products containing preservatives for lasting protection from microorganisms.

Biguanides↗
PubMed1994

Field effectiveness of needle disinfection among injecting drug users.

To examine the putative protective effect of disinfectant use on HIV seroconversion among injecting drug users, we conducted a nested case-control study of black heterosexuals comparing 34 HIV seroconverters with 154 persistent seronegatives matched on gender, cocaine injection (yes/no), date of study entry, and duration of follow-up. Injecting drug users who reported using disinfectant all the time had an odds ratio of seroconversion of 0.87, as compared with those who reported no use of disinfectants; the corresponding odds ratio was 1.00 for those who used disinfectants less than all the time. We examined the effect of drug use and sex practice variables, and responses to a socially desirable responding scale as possible confounders for the effect of needle disinfection on HIV seroconversion; the adjusted odds ratios for disinfectant use and HIV seroconversion were unchanged in this analysis. Despite limited statistical power and the potential for residual confounding, these data suggest that disinfection of injection equipment is not a substitute for abstinence from drugs or use of sterile injection equipment.

1-Propanol↗
PubMed1977

[Virucidal efficacy of a chemical instrument surface disinfectant ("Gigasept") against coxsackie virus type B3. II. Investigation in the instrumental surface test (author's transl)].

The virucidal efficacy of the chemical disinfectant "Gigasept" on the basis of succine dialdehyde and formaldehyde was tested with an instrumental surface test which was elaborated for the control of instrument-surface disinfectants. These must be able to inactivate viruses on plastics, rubber and metal. Therefore, PVC tubes, PVC dental suction tubes, red rubber catheter and aluminium surfaces were included in this investigation. Coxsackie virus type B3 served as test virus. The surfaces were coated with liquid virus suspensions with the exemption of the aluminium surface which was contaminated with a gelatinous virus suspension. The instrumental surface test procedure enabled not only the analysis of the specific virucidal effect but also the evaluation of the unspecific virus adsorption onto the surface as well as the unspecific virus resuspension from the surface. Parameter for the disinfectant activity was the virus inactivation kinetic, i.e. the interdependence of the titer reduction vs. disinfectant contact time of a 5% solution of "Gigasept". An optimal disinfection must gain absence of virus, a titer reduction of larger than or equal to 103ID 50 and a significant titer decrease of p less than 0.0001. According to these criteria an optimal disinfection was achieved with a 5% Gigasept concentration after 4 hours. The different surfaces did not influence the virucidal activity of the disinfectant. The results of the instrumental surface tests confirmed those of the suspension test.

Disinfectants↗
PubMed1997

[Sensitivity to disinfectants of methicillin resistant Staphylococcus aureus strains (MRSA) and gentamicin resistant strains].

The aim of the study was to find out whether methicillin-resistant S. aureus strains (MRSA) are tolerant in a higher degree to disinfectants, and whether a correlation exists between lower sensitivity to these agents and resistance to gentamicin. The study was carried out on 30 strains of MRSA and 20 of MSSA isolated from various clinical materials in various regions of the country. Among the studied MRSA 24 strains were resistant and 6 were sensitive to gentamicin, and in MSSA 3 strains were resistant and 17 sensitive to this antibiotic. The sensitivity to four disinfectants: Manusan, Sterinol, Septyl R and Lysoformin Spezial was determined by measurement of MIC (minimal inhibitory concentration) in agar medium. Most MRSA in Poland showed decreased sensitivity to these disinfectants. Among gentamicin-sensitive and resistant MRSA strains the proportions of strains with higher tolerance of three disinfectants (Manusan, Sterinol and Lysoformin Spezial) were very similar. Reduced sensitivity to disinfectants was found in all gentamicin-resistant MSSA. These data indicate that S. aureus strains possess various mechanisms of tolerance of disinfectants. Nearly half the studied strains (46%) had decreased sensitivity to all three preparations (Manusan, Sterinol and Lysoformin Spezial) belonging to various chemical groups this seems to indicate that increased tolerance to these disinfectants is a non-specific feature of S. aureus strains.

Disinfectants↗
PubMed1997

Application of automated thermal disinfection instead of sterilisation procedures for treatment of rotating dental instruments: efficacy against viruses?

In dentistry it is of primary importance to take into consideration microbial transfer due to the nature of the construction of rotating dental instruments. This aspect was the starting point for our research with the question whether or not sterilisation is fundamentally necessary for slow and high speed hand pieces to make them "safe" out of a virological point of view, or whether a thermal disinfection could also possibly be adequate for this purpose. In this context, we tested the efficiency of the cleaning and disinfection capacity of an automated steam disinfection and sterilisation unit (Sirona Hygiene Center, Siemens, AG, Bensheim) intended to the hygienic treatment of dental instruments with respect to viruses. In model tests the corresponding instruments were experimentally infected with herpes simplex virus type 1 (HSV) and simian vacuoling virus (SV40). As indicator systems we used for both cell cultures (measurement of the degree of infectiosity) and (for HSV) polymerase chain reactions (PCR; determination of viral nucleic acids). In the tests for (residual) infectiosity after thermal disinfection (as an isolated step of the Hygienic Centre) and also for a combination of cleaning and subsequent thermal disinfection (also after protein application), no infectious virus could be found in the interior of the slow handpieces and turbines tested. In opposite to this, infectious HSV and SV40 could be found after completion of every isolated cleaning program in the turbine (in all three ducts) and in the slow handpiece (only in the gearbox duct in the case of HSV, and in the case of SV40 also in the water and air ducts in very small amounts). The PCR analyses showed that no nucleic acids could be found in both instruments (in the air and water ducts) following a practice-relevant combination of cleaning and disinfection, but that PCR-positive signals were obtained for the larger-volume gearbox and drive and return air ducts in 1 or 2 of 3 test samples. The detection of viral nucleic acid proves that it is not a matter of complete removal of the infectious agents from the instruments, but rather that they are simply inactivated. Since the test samples did not show similar amounts of viral nucleic acid, it demonstrates the strong influence of the basic parameters (efficiency of the virus contamination, flushing conditions and the like). Our experimental model demonstrate that thermal disinfection may be adequate to prevent virus contamination of rotating dental instruments, while compulsory sterilisation is not mandatory. Further studies are necessary to demonstrate whether the present data are applicable for rotating dental instruments from other manufactures.

Automation↗
PubMed2001

Microbiological methods for testing disinfectant efficiency on Pseudomonas biofilm.

Biofilms of the Gram-negative bacteria Pseudomonas aeruginosa and Pseudomonas fragi were grown on stainless steel surfaces (AISI 304, 2B) for 4 days in slime broth. These biofilms were treated with four commercial disinfectants. The disinfectants were alcohol-based, tenside-based, peroxide-based and chlorine-based products, covering most disinfectant types used in the food industry. The effects of the disinfectants on the bacterial cells were first investigated in suspension using the permeabilisation test, which is based on fluorescence assessment of hydrophobic 1-N-phenyl-naphtylamine (NPN). The surfaces covered with disinfectant-treated biofilms were investigated using conventional cultivation, impedimetry and epifluorescence microscopy in combination with image analysis of preparations stained with the DNA-stain acridine orange and with the metabolic indicator system CTC-DAPI. The results showed that the tenside-based and peroxide-based disinfectants permeabilised the cells in suspension. The overall biofilm results showed that of the agents tested, the peroxide-based and chlorine-based disinfectants acted most effectively on cells in biofilms.

Journal Article↗