Insights
Glossary.
The technical terms used on this website, each explained in one or two sentences in German and English. Every entry links to the page that covers the topic in depth.
50 terms
Antibacterial activity R
Testing & measurement (4)Value defined in ISO 22196 and JIS Z 2801: the difference between the mean log counts of viable bacteria on untreated and treated specimens after 24 hours. An R of 2 means 99 % fewer bacteria than on the untreated specimen.
More on: Test standards explainedAntimicrobial
Activity terms (6)Umbrella term for activity against microorganisms: bacteria, fungi, viruses or parasites. Which groups a product actually covers must be demonstrated separately for each group.
More on: Antibacterial or antimicrobial?Bactericidal
Activity terms (6)Killing bacteria. In the laboratory a substance counts as bactericidal if the concentration needed for a 99.9 % kill is at most four times the minimum inhibitory concentration; disinfectant standards set their own minimum values.
More on: Antibacterial or antimicrobial?Bacteriostatic
Activity terms (6)Inhibiting the multiplication of bacteria without killing them. Once exposure ends, the bacteria can grow again.
More on: Antibacterial or antimicrobial?Biocidal product
Regulation & patents (4)Substance or mixture containing active substances intended to destroy, deter, control or prevent the action of harmful organisms by means other than mere physical or mechanical action (Article 3(1)(a) BPR). In principle it requires authorisation under the Regulation.
More on: Treated articlesBiocompatibility
Medicine (5)Ability of a material to perform with an appropriate host response in a specific application. For medical devices it is evaluated under the ISO 10993 series within a risk management process.
More on: Medical devicesBiofilm
Microbiology (6)Community of microorganisms attached to a surface and embedded in a self-produced matrix of extracellular polymeric substances. Cells in a biofilm are often considerably less susceptible to active substances than free-floating cells.
More on: Preventing biofilmBiofouling
Water & membranes (3)Unwanted colonisation of technical surfaces by microorganisms, algae or larger organisms, for example on membranes, heat exchangers or ship hulls. On membranes it is also called biological fouling.
More on: Water & membranesCarvacrol
botanikMonoterpenoid phenol and the main active constituent of oregano (Origanum vulgare). It is a structural isomer of thymol.
More on: Origin & botanical activesCationic
Chemistry & materials (11)Positively charged. In acidic conditions chitosan is a cationic polymer because its amino groups take up protons (–NH₃⁺).
More on: ChitosanCAUTI
Medicine (5)Catheter-associated urinary tract infection: a urinary tract infection in a patient with an indwelling urinary catheter.
More on: Medical devicesCFU (colony-forming unit)
Testing & measurement (4)Counting unit for viable microorganisms: each CFU grows into one visible colony on the culture medium. Counts are given as CFU per millilitre, gram or surface area.
More on: EvidenceChitin
Chemistry & materials (11)Linear polysaccharide of β-(1→4)-linked N-acetyl-D-glucosamine. It is the structural material of crustacean shells, fungal cell walls and insect cuticles, and one of the most abundant biopolymers after cellulose.
More on: ChitosanChitosan
Chemistry & materials (11)Polysaccharide of D-glucosamine and N-acetyl-D-glucosamine obtained by deacetylating chitin. It dissolves in dilute acids, where it carries positive charges.
More on: ChitosanCinnamaldehyde
botanikAromatic aldehyde and the main active constituent of cinnamon bark (Cinnamomum). It gives cinnamon its characteristic odour.
More on: Origin & botanical activesCLABSI
Medicine (5)Central line-associated bloodstream infection: a bloodstream infection in a patient with a central venous catheter that is not related to an infection at another site.
More on: Medical devicesCompound (plastics)
Processing (7)Ready-to-use plastic formulation in which polymer and additives are already melt-blended at their final concentration. It is made by compounding, usually in a twin-screw extruder.
More on: Plastics & masterbatchCPC class
Regulation & patents (4)Class in the Cooperative Patent Classification, the joint classification system of the European Patent Office and the US Patent and Trademark Office. The Z-Chitosan patents carry classes including C08B37/003, C08J3/22 and C08L5/08.
More on: PatentsCytotoxicity
Medicine (5)Damage to cells caused by a substance or material. For medical devices it is tested in vitro on cell cultures in accordance with ISO 10993-5.
More on: Test standards explainedDegree of deacetylation (DDA)
Chemistry & materials (11)Percentage of glucosamine units with a free amino group among all units in the chain; its complement is the degree of acetylation (DA). Typically 60–95 % for chitosan, it influences charge density and solubility.
More on: ChitosanDip coating
Processing (7)Coating process in which a part is immersed in a solution or dispersion and withdrawn at a controlled speed. Film thickness depends on factors such as withdrawal speed and viscosity.
More on: Medical devicesEmulsion cross-linking
Chemistry & materials (11)Process in which a polymer is cross-linked inside the droplets of an emulsion so that solid particles form. The Z-Chitosan patents describe a multi-stage emulsion cross-linking of chitosan with plant extracts.
More on: TechnologyEPS matrix
Microbiology (6)Extracellular polymeric substances: polysaccharides, proteins, nucleic acids and lipids secreted by microorganisms. They hold the biofilm together, anchor it to the surface and protect the cells.
More on: Preventing biofilmEugenol
botanikPhenylpropanoid and the main active constituent of clove (Syzygium aromaticum). It gives clove oil its characteristic odour.
More on: Origin & botanical activesExtrusion
Processing (7)Continuous process in which molten plastic is forced through a shaping die. It produces pipes, tubing, profiles, films and fibres.
More on: Plastics & masterbatchFungicidal
Activity terms (6)Killing fungi, i.e. moulds and yeasts; a merely inhibiting effect is called fungistatic. Antifungal is the umbrella term for activity against fungi, and yeasticidal refers to activity against yeasts.
More on: Antibacterial or antimicrobial?Glucosamine
Chemistry & materials (11)Amino sugar (2-amino-2-deoxy-D-glucose). As a building block of chitosan it carries the free amino group that takes up a proton in acidic conditions.
More on: ChitosanGram-positive / Gram-negative
Microbiology (6)Classification of bacteria by Gram staining. Gram-positive bacteria have a thick peptidoglycan layer with teichoic acids; Gram-negative bacteria have a thin peptidoglycan layer and an outer membrane containing lipopolysaccharide.
More on: TechnologyInclusion
Chemistry & materials (11)Enclosure or incorporation of a substance within a carrier or matrix structure. The term appears in the title of US patent 11,708,424 B1 (“Inclusion of chitosan and herbal extracts as an antimicrobial agent”).
More on: PatentsInjection moulding
Processing (7)Process in which molten plastic is injected under pressure into a cooled mould, where it solidifies. It produces moulded parts such as handles, housings and connectors.
More on: Plastics & masterbatchLeaching / non-leaching (contact-active)
Activity terms (6)Leaching systems release their active substance into the surroundings and also act near the surface. Bound, contact-active systems are designed to act where microorganisms touch the surface, without significant release.
More on: Leaching vs non-leachingLipopolysaccharide (LPS)
Microbiology (6)Major component of the outer membrane of Gram-negative bacteria; its phosphate groups contribute to the negative charge of the cell surface. Released LPS acts as an endotoxin.
More on: TechnologyLog reduction
Testing & measurement (4)Reduction in microbial count expressed in powers of ten. 1 log equals 90 %, 2 log 99 %, 3 log 99.9 % and 4 log 99.99 %.
More on: EvidenceMasterbatch
Processing (7)Pellets in which an additive is highly concentrated in a carrier polymer. They are added to the base plastic in small proportions during processing.
More on: Plastics & masterbatchMDR
Regulation & patents (4)Regulation (EU) 2017/745 on medical devices, applicable since 26 May 2021. It governs classification (Annex VIII), conformity assessment and clinical evaluation of medical devices in the EU, among other things.
More on: RegulatoryN-acetylglucosamine
Chemistry & materials (11)Acetylated form of glucosamine and the building block of chitin. Some units in chitosan remain acetylated, and N-acetylglucosamine is also a component of bacterial peptidoglycan.
More on: ChitosanPadder
Processing (7)Roller machine used in textile finishing: the fabric passes through a bath of finishing agent and is squeezed between two rollers, leaving a defined amount of liquor in the fabric (pad application).
More on: TextilesPeptidoglycan
Microbiology (6)Mesh of sugar chains (N-acetylglucosamine and N-acetylmuramic acid) cross-linked by short peptides. It gives the bacterial cell its shape and mechanical strength.
More on: TechnologypKa
Chemistry & materials (11)Negative base-10 logarithm of the acid dissociation constant: the pH at which half of a group is protonated. For the amino groups of chitosan it is about 6.2–6.5, depending on DDA.
More on: ChitosanProtonation
Chemistry & materials (11)Addition of a proton (H⁺) to a molecule. In chitosan, –NH₂ becomes the charged group –NH₃⁺; the share depends on pH.
More on: ChitosanReverse osmosis (RO)
Water & membranes (3)Membrane process in which water is forced through a semi-permeable membrane at a pressure above the osmotic pressure. Dissolved salts and most other solutes are retained.
More on: Water & membranesTeichoic acid
Microbiology (6)Anionic polymers of glycerol or ribitol phosphate in the cell wall of Gram-positive bacteria. They contribute substantially to the negative surface charge of these cells.
More on: TechnologyTextile finish
Processing (7)Finishing step that gives a textile an additional property, such as water repellency, crease resistance or antimicrobial activity. It is applied by padding, spraying or exhaust processes, among others.
More on: TextilesThin-film composite membrane (TFC)
Water & membranes (3)Membrane consisting of a very thin, selective polyamide layer on a porous support, usually polysulfone on a non-woven backing. It is the standard design for reverse osmosis and nanofiltration.
More on: Water & membranesThymol
botanikMonoterpenoid phenol and the main active constituent of thyme (Thymus vulgaris). It is a structural isomer of carvacrol.
More on: Origin & botanical activesTreated article
Regulation & patents (4)Under Article 3(1)(l) of the Biocidal Products Regulation, any substance, mixture or article that has been treated with, or intentionally incorporates, biocidal products. If a biocidal property is claimed, the labelling duty under Article 58(3) applies.
More on: Treated articlesVAP
Medicine (5)Ventilator-associated pneumonia: pneumonia in a mechanically ventilated patient that, under common definitions, arises more than 48 hours after intubation.
More on: Medical devicesVirucidal
Activity terms (6)Inactivating viruses. For disinfectants, EN 14476 distinguishes full virucidal activity, limited-spectrum virucidal activity and activity against enveloped viruses.
More on: Antibacterial or antimicrobial?Z-Chitosan
Chemistry & materials (11)Z-Chitosan is an inclusion complex of chitosan and at least one plant extract, formed in the presence of a catalyst (US 11,708,424). It is produced by multi-stage emulsion cross-linking and dried to a powder; as a masterbatch it goes into plastics, polymers and fabrics (US 12,071,490).
More on: TechnologyZone of inhibition
Testing & measurement (4)Clear ring without growth around a sample on an inoculated agar plate. It forms when an active substance diffuses from the sample into the agar and therefore indicates release.
More on: Leaching vs non-leaching
Sources12
- Verordnung (EU) Nr. 528/2012 (BPR), Art. 3 Abs. 1 Buchst. a und l, Art. 58. https://eur-lex.europa.eu/eli/reg/2012/528/oj
- Verordnung (EU) 2017/745 über Medizinprodukte (MDR). https://eur-lex.europa.eu/eli/reg/2017/745/oj
- ISO 22196 (Messung der antibakteriellen Aktivität auf Kunststoffen und anderen nicht porösen Oberflächen) · ISO 10993-1 und ISO 10993-5 (biologische Beurteilung von Medizinprodukten; Zytotoxizität in vitro).
- Tarka P., Nitsch-Osuch A. (2021): Evaluating the Virucidal Activity of Disinfectants According to European Union Standards. Viruses 13(4):534.
- Ishak A., Mazonakis N., Spernovasilis N., Akinosoglou K., Tsioutis C. (2025): Bactericidal versus bacteriostatic antibacterials. Journal of Antimicrobial Chemotherapy 80(1):1–17.
- Wang Q. Z. et al. (2006): Protonation constants of chitosan with different molecular weight and degree of deacetylation. Carbohydrate Polymers 65(2):194–201.
- Younes I., Rinaudo M. (2015): Chitin and Chitosan Preparation from Marine Sources. Marine Drugs 13(3):1133–1174.
- Flemming H.-C., Wingender J. (2010): The biofilm matrix. Nature Reviews Microbiology 8(9):623–633.
- Stoodley P., Sauer K., Davies D. G., Costerton J. W. (2002): Biofilms as complex differentiated communities. Annual Review of Microbiology 56:187–209.
- Williams D. F. (2008): On the mechanisms of biocompatibility. Biomaterials 29(20):2941–2953.
- American Thoracic Society, Infectious Diseases Society of America (2005): Guidelines for the management of adults with hospital-acquired, ventilator-associated, and healthcare-associated pneumonia. American Journal of Respiratory and Critical Care Medicine 171(4):388–416.
- US 11,708,424 B1 und US 12,071,490 B2 (Titel, CPC-Klassen). https://patents.google.com/patent/US11708424B1/en · https://patents.google.com/patent/US12071490B2/en
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