Editing Bactericide

{{Short description|Agent which kills bacteria}}

A '''bactericide''' or '''bacteriocide''', sometimes abbreviated '''Bcidal''', is a substance which kills [[bacteria]]. Bactericides are [[disinfectant]]s, [[antiseptic]]s, or [[antibiotic]]s.<ref>{{cite journal
|journal=Clin Microbiol Rev
|year=1999
|volume=12
|issue=1
|pages=147–179
|pmc=88911
|title=Antiseptics and Disinfectants: Activity, Action, and Resistance
|pmid=9880479 | last1 = McDonnell | first1 = G | last2 = Russell | first2 = AD | doi=10.1128/cmr.12.1.147}}</ref>
However, material surfaces can also have bactericidal properties based solely on their physical surface structure, as for example biomaterials like insect wings.

==Disinfectants==
The most used  [[disinfectant]]s are those applying
*active [[chlorine]] (i.e., [[hypochlorite]]s, [[chloramine]]s, [[sodium dichloroisocyanurate|dichloroisocyanurate]] and [[trichloroisocyanurate]], wet chlorine, [[chlorine dioxide]], etc.),
*active [[oxygen]] ([[peroxide]]s, such as [[peracetic acid]], [[potassium persulfate]], [[sodium perborate]], [[sodium percarbonate]], and [[urea perhydrate]]),
*[[iodine]] ([[povidone-iodine]], [[Lugol's solution]], iodine tincture, iodinated nonionic surfactants),
*concentrated [[alcohols]] (mainly [[ethanol]], [[1-propanol]], called also [[n-propanol]] and [[2-propanol]], called [[isopropanol]] and mixtures thereof; further, [[2-phenoxyethanol]] and 1- and [[2-phenoxypropanol]]s are used),
*[[phenols|phenolic substances]] (such as [[phenol]] (also called "carbolic acid"), [[cresol]]s such as [[thymol]], halogenated (chlorinated, brominated) phenols, such as [[hexachlorophene]], [[triclosan]], [[trichlorophenol]], [[tribromophenol]], [[pentachlorophenol]], salts and isomers  thereof),
*[[cationic surfactants]], such as some [[quaternary ammonium cation]]s (such as [[benzalkonium chloride]], [[cetyl trimethylammonium bromide]] or chloride, [[didecyldimethylammonium chloride]], [[cetylpyridinium chloride]], [[benzethonium chloride]]) and others, non-quaternary compounds, such as [[chlorhexidine]], [[glucoprotamine]], [[octenidine]] dihydrochloride etc.),
*strong [[oxidizer]]s, such as [[ozone]] and [[permanganate]] solutions;
*[[heavy metals]] and their salts, such as colloidal [[silver]], [[silver nitrate]], [[Mercury(II) chloride|mercury chloride]], [[organomercury|phenylmercury]] salts, [[copper sulfate]], [[copper oxide-chloride]] etc. Heavy metals and their salts are the most toxic and environment-hazardous bactericides and therefore their use is strongly discouraged or prohibited
* strong [[acid]]s (phosphoric, nitric, sulfuric, amidosulfuric, toluenesulfonic acids), pH < 1, and
*[[alkali]]s (sodium, potassium, calcium hydroxides), such as of pH > 13, particularly under elevated temperature (above 60&nbsp;°C), kills bacteria.

==Antiseptics==
As [[antiseptic]]s (i.e., germicide agents that can be used on human or animal body, skin, mucosae, wounds and the like), few of the above-mentioned disinfectants can be used, under proper conditions (mainly concentration, pH, temperature and toxicity toward humans and animals). Among them, some important are
*properly diluted [[chlorine]] preparations (f.e. [[Dakin's Solution|Dakin's solution]], 0.5% sodium or potassium hypochlorite solution, pH-adjusted to pH 7–8, or 0.5–1% solution of sodium benzenesulfochloramide ([[chloramine]] B)), some
*[[iodine]] preparations, such as [[iodophor|iodopovidone]] in various [[Galenic formulation|galenic]]s (ointment, solutions, wound plasters), in the past also [[Lugol's solution]],
*[[peroxide]]s such as urea perhydrate solutions and pH-[[Buffer solution|buffered]] 0.1 – 0.25% peracetic acid solutions,
*[[Alcohol (chemistry)|alcohol]]s with or without antiseptic additives, used mainly for skin antisepsis,
*weak [[organic acids]] such as [[sorbic acid]], [[benzoic acid]], [[lactic acid]] and [[salicylic acid]]
*some [[phenol]]ic compounds, such as [[hexachlorophene]], [[triclosan]] and Dibromol, and
*cationic surfactants, such as 0.05–0.5% benzalkonium, 0.5–4% [[chlorhexidine]], 0.1–2% octenidine solutions.
Others are generally not applicable as safe antiseptics, either because of their [[corrosive]] or [[toxic]] nature.

==Antibiotics==
Bactericidal [[antibiotic]]s kill bacteria; [[bacteriostatic]] antibiotics slow their growth or reproduction.

Bactericidal antibiotics that inhibit cell wall synthesis: the [[beta-lactam antibiotics]] ([[penicillin]] derivatives ([[penam]]s), [[cephalosporin]]s ([[cephem]]s), [[monobactam]]s, and [[carbapenem]]s) and [[vancomycin]].

Also bactericidal are [[daptomycin]], [[fluoroquinolone]]s, [[metronidazole]], [[nitrofurantoin]], [[co-trimoxazole]], [[telithromycin]].

[[Aminoglycoside|Aminoglycosidic antibiotics]]  are usually considered bactericidal, although they may be bacteriostatic with some organisms.

As of 2004, the distinction between bactericidal and bacteriostatic agents appeared to be clear according to the basic/clinical definition, but this only applies under strict laboratory conditions and it is important to distinguish microbiological and clinical definitions.<ref>{{cite journal
|title=Clinical Relevance of Bacteriostatic versus Bactericidal Mechanisms of Action in the Treatment of Gram-Positive Bacterial Infections 
|journal=Clin Infect Dis 
|year=2004
|volume=38
|issue=6
|pages=864–870
|doi=10.1086/381972
|pmid=14999632 | last1 = Pankey | first1 = GA | last2 = Sabath | first2 = LD|doi-access=free}}</ref> The distinction is more arbitrary when agents are categorized in clinical situations. The supposed superiority of bactericidal agents over bacteriostatic agents is of little relevance when treating the vast majority of infections with [[gram-positive bacteria]], particularly in patients with uncomplicated infections and noncompromised immune systems. Bacteriostatic agents have been effectively used for treatment that are considered to require bactericidal activity. Furthermore, some broad classes of antibacterial agents considered bacteriostatic can exhibit bactericidal activity against some bacteria on the basis of in vitro determination of MBC/MIC values. At high concentrations, bacteriostatic agents are often bactericidal against some susceptible organisms. The ultimate guide to treatment of any infection must be clinical outcome.

==Surfaces==
Material surfaces can exhibit bactericidal properties because of their crystallographic surface structure.

Somewhere in the mid-2000s it was shown that metallic [[nanoparticle]]s can kill bacteria. The effect of a [[silver nanoparticle]] for example depends on its size with a preferential diameter of about 1&ndash;10&nbsp;nm to interact with bacteria.<ref>{{Cite journal |last1=Morones |first1=Jose Ruben |last2=Elechiguerra |first2=Jose Luis |last3=Camacho |first3=Alejandra |last4=Holt |first4=Katherine |last5=Kouri |first5=Juan B |last6=Ramírez |first6=Jose Tapia |last7=Yacaman |first7=Miguel Jose |date=2005-10-01 |title=The bactericidal effect of silver nanoparticles |journal=Nanotechnology |language=en |volume=16 |issue=10 |pages=2346–2353 |doi=10.1088/0957-4484/16/10/059 |pmid=20818017 |bibcode=2005Nanot..16.2346R |issn=0957-4484}}</ref>

In 2013, [[cicada]] wings were found to have a selective anti-gram-negative bactericidal effect based on their physical surface structure.<ref>{{Cite journal |last1=Hasan |first1=Jafar |last2=Webb |first2=Hayden K. |last3=Truong |first3=Vi Khanh |last4=Pogodin |first4=Sergey |last5=Baulin |first5=Vladimir A. |last6=Watson |first6=Gregory S. |last7=Watson |first7=Jolanta A. |last8=Crawford |first8=Russell J. |last9=Ivanova |first9=Elena P. |date=October 2013 |title=Selective bactericidal activity of nanopatterned superhydrophobic cicada Psaltoda claripennis wing surfaces |journal=Applied Microbiology and Biotechnology |language=en |volume=97 |issue=20 |pages=9257–9262 |doi=10.1007/s00253-012-4628-5 |pmid=23250225 |s2cid=16568909 |issn=0175-7598}}</ref> Mechanical deformation of the more or less rigid [[nanopillar]]s found on the wing releases energy, striking and killing bacteria within minutes, hence called a mechano-bactericidal effect.<ref>{{Cite journal |last1=Ivanova |first1=Elena P. |last2=Linklater |first2=Denver P. |last3=Werner |first3=Marco |last4=Baulin |first4=Vladimir A. |last5=Xu |first5=XiuMei |last6=Vrancken |first6=Nandi |last7=Rubanov |first7=Sergey |last8=Hanssen |first8=Eric |last9=Wandiyanto |first9=Jason |last10=Truong |first10=Vi Khanh |last11=Elbourne |first11=Aaron |date=2020-06-09 |title=The multi-faceted mechano-bactericidal mechanism of nanostructured surfaces |journal=Proceedings of the National Academy of Sciences |language=en |volume=117 |issue=23 |pages=12598–12605 |doi=10.1073/pnas.1916680117 |doi-access=free |issn=0027-8424 |pmid=32457154|pmc=7293705 |bibcode=2020PNAS..11712598I }}</ref>

In 2020 researchers combined cationic polymer adsorption and femtosecond laser surface structuring to generate a bactericidal effect against both gram-positive ''[[Staphylococcus aureus]]'' and gram-negative ''[[Escherichia coli]]'' bacteria on [[borosilicate glass]] surfaces, providing a practical platform for the study of the bacteria-surface interaction.<ref>{{cite journal | last1=Chen |first1=C. |last2=Enrico |first2=A. |display-authors=etal| title = Bactericidal surfaces prepared by femtosecond laser patterning and layer-by-layer polyelectrolyte coating | doi=10.1016/j.jcis.2020.04.107 | journal = Journal of Colloid and Interface Science| volume = 575 | pages = 286–297 | year = 2020 |pmid=32380320 |bibcode=2020JCIS..575..286C | doi-access = free }}</ref>

==See also==
* [[List of antibiotics]]
* [[Microbicide]]
*[[Virucide]]

== References ==
{{Reflist}}
{{Wiktionary|bactericide}}

{{Pharmacology}}
{{Authority control}}

[[Category:Bactericides| ]]