Control of Microbial Growth Part 1B

other chemicals commonly used for disinfection are the ____ in the periodic table.

halogens

these elements share the properties of forming anions in a solution and have low melting and boiling points:

halogens

works by oxidizing cellular components like amino acids, nucleotides, and fatty acids, which stabilizes macromolecules:

iodine

often used as a topical tincture, but it may cause staining or skin irritation:

iodine

compound of iodine complexed with an organic molecule that increases iodine’s stability and efficacy:

iodophor

brand of povidone-iodine used as a hand scrub by medical personnel before surgery and for topical antisepsis of a patient’s skin before incision:

betadine

when chlorine gas is mixed with water, it produces a strong oxidant called ____, which is uncharged and enters cells easily.

hypochlorous

used in municipal drinking water and wastewater treatment plants:

chlorine gas

chemical component of household bleach and is used for a variety of disinfecting purposes:

sodium hypochlorite

chlorinated compounds widely used as disinfectants:

chloramines

derivatives of ammonia by substitution of one, two, or all three hydrogen atoms with chlorine atoms:

chloramines

chloramines are relatively stable and release chlorine over long periods of time. true or false?

true

has antimicrobial properties that contribute to the prevention of dental caries (cavities):

fluorine

main active ingredient of toothpaste:

fluoride

can incorporate into tooth enamel, making it more resistant to corrosive acids produced by the fermentation of oral microbes:

fluoride

enhances the uptake of calcium and phosphate ions in tooth enamel, promoting remineralization:

fluoride

rapidly denatures proteins, inhibiting cellular processes:

alcohols

disrupts membranes and leads to cell lysis:

alcohols

typically used at concentrations of ~70% aqueous solutions:

alcohols

work better in aqueous solutions than 100% alcohol solutions because higher concentrations of alcohol rapidly coagulate surface proteins, which prevents effective penetration of cells:

alcohols

chemical name for ethanol:

ethyl alcohol

chemical name for rubbing alcohol:

isopropyl alcohol

another name for isopropyl alcohol:

isopropanol

list the 2 most common alcohol disinfectants. (*hint: common names)

ethanol; rubbing alcohol

tend to be bactericidal and fungicidal and may also be viricidal for enveloped viruses only:

alcohols

not sporicidal but can inhibit the processes of sporulation and germination:

alcohols

used to make tinctures with other antiseptics such as iodine tinctures:

alcohols

group of chemical compounds that lower the surface tension of water:

surfactants

surface active agents:

surfactants

major ingredient in soaps and detergents:

surfactants

salts of long-chain fatty acids and have both polar and nonpolar regions, allowing them to interact with polar and nonpolar regions in other molecules:

soaps

interacts with nonpolar oils and grease to create emulsions in water, loosening and lifting away dirt and microbes from surfaces and skin:

soaps

do not kill or inhibit microbial growth so they are not considered antiseptics or disinfectants:

soaps

can emulsify lipids, fats, and oils by interacting with water through their hydrophilic heads and with the lipid at their hydrophobic tails:

soaps

contain synthetic surfactant molecules with both polar and nonpolar regions and are more soluble than soaps:

detergents

can insert into membranes (lipid bilayers) and disrupt them, giving them bactericidal properties:

detergents

used for laundry and have a negatively charged anion at one end attached to a long hydrophobic chain:

anionic detergents

have a positively charged cation and include quaternary ammonium salts quats):

cationic detergents

quats are bactericidal. true or false?

true

amphipathic and are similar to phospholipids with hydrophilic and hydrophobic ends:

quats

can infiltrate the phospholipid plasma membranes of bacterial cells and disrupt their integrity, leading to death of the cell:

quats

cationic molecules with antiseptic properties:

bisbiguanide

chlorhexidine is an example of:

bisbiguanide

bisbiguanide that gained popularity because it acts faster than chlorhexidine:

alexidine

group of strong disinfecting chemicals that act by replacing a hydrogen atom within a molecule with an alkyl group and inactivates enzymes and nucleic acids:

alkylating agents

alkylating agent that is commonly used in solution at a concentration of 37% or as a gaseous disinfectant:

formaldehyde

formaldehyde at a concentration at 37%:

formalin

replaces hydrogen atoms with alkyl groups:

alkylating agents

has two reactive aldehyde groups and allows it to act more quickly than formaldehyde:

glutaraldehyde

newer disinfecting compound that has two reactive aldehyde groups linked by an aromatic bridge:

OPA

what does OPA stand for?

O-phthalaldehyde

type of alkylating agent that is used for gaseous sterilization:

ethylene oxide

ethylene oxide exposure is a form of hot sterilization. true or false?

false

can penetrate packaging and is effective at lower temperatures, making it an ideal sterilant for sensitive medical and laboratory equipment:

ethylene oxide

kills microbes by binding to and damaging DNA:

beta-propionolactone