Kab lus no tsom rau cov antimicrobial tshuab ntawm Gemini los, uas yuav tsum muaj kev ua haujlwm hauv kev tua cov kab mob thiab tuaj yeem muab qee qhov kev pab hauv kev kis tus kab mob tshiab.
Surfactant, uas yog ib qho kev cog lus ntawm cov kab lus saum npoo av, nquag thiab tus neeg sawv cev. Surfactants yog cov tshuaj uas muaj cov chaw nyob ntawm thaj chaw thiab cuam tshuam thiab muaj peev xwm ua tau zoo dua qub, ua kom muaj peev xwm sib dhos, kev ua kom zoo dua qub, ua kom muaj zog tshaj plaws hauv cov kev sib tw sib txawv thiab yog li muaj ntau cov ntawv thov haujlwm. Surfactants muaj zoo dispersibility, wettity, muaj peev xwm tseem ceeb, thiab muaj lub peev xwm tseem ceeb hauv kev txhim kho cov txheej txheem, thiab ua kom muaj zog siv hluav taws xob, thiab ua kom muaj zog ntau dua Cov. Nrog rau kev txhim kho ntawm tib neeg thiab kev nce qib txuas ntxiv ntawm lub ntiaj teb kev lag luam, xws li cov tshuaj tua kab mob hauv Tebchaws, xws li cov khoom noj ua haus txhua hnub, kev kho mob tshiab, kev kho tshiab thiab biopharraceuticals.
Cov pab pawg Amphiphilic "Amphiphilic" cov lus teb hydrophilic, thiab lawv cov qauv molrophobic tau pom hauv daim duab 1 (a).
Tam sim no, nrog kev txhim kho ntawm kev ua kom zoo thiab ua haujlwm rau kev tsim khoom lag luam, yog qhov tseem ceeb kom pom thiab txhim kho surfactants nrog cov khoom siab dua thiab nrog cov qauv tshwj xeeb. Qhov kev tshawb nrhiav ntawm Gemini Surfactants Txuas txuas ntxiv rau cov khoob thiab ua tau raws li cov kev xav tau ntawm kev lag luam tsim khoom. Ib lub gemini surfactant yog ib qho compound nrog ob pawg hydroughilic (feem ntau ionic lossis tsis muaj hydrophilic cov khoom) thiab ob lub pob zeb hydrophobic alkyl.
Raws li muaj nyob hauv daim duab 1 (b), hauv kev sib piv rau ib leeg-sawin surfactants, Gemini Surfactants Txuas Txuas ob Hydrophilic pawg ua ke los ntawm kev sib txuas pawg (txuas ntxiv). Hauv ntej, tus qauv ntawm Gemini Surfactant tuaj yeem to taub raws li tsim los ntawm cleeverly bonding ob hydleastal surfactant ua ke nrog kev sib txuas pawg.
Tus qauv tshwj xeeb ntawm Gemini Surfactant ua rau nws cov kev ua si siab, uas yog vim yog:
(1) Cov nyhuv hydrophobic nyhuv ntawm ob lub pob hydrophobic tw saw ntawm lub Gemini Surfactant Molecule thiab nce siab ntawm surfactant kom tawm ntawm cov tshuaj aqueous.
(2) Qhov kev nyiam ntawm hydrophilic lub taub hau pab pawg sib cais, tshwj xeeb yog electrostatic repulsion, yog cov muaj zog tsis muaj zog los ntawm tus nplaim taws;
(3) Tus qauv tshwj xeeb ntawm Gemini Comfactants cuam tshuam rau lawv tus cwj pwm hauv a
Gemini Surfactants muaj qhov chaw siab dua (thaj chaw) kev ua si, qis dua cov tswv yim thiab muaj peev xwm ua tau zoo dua thiab cov tshuaj tua kabmob uas muaj peev xwm piv nrog surfactants. Yog li ntawd, kev txhim kho thiab kev siv cov gemini los yog muaj qhov tseem ceeb rau kev txhim kho thiab kev siv ntawm surfactants.
Lub "Amphiphilic qauv" ntawm cov kev sib luag surfactants muab lawv tshwj xeeb cov khoom ntiag tug. Raws li muaj nyob hauv daim duab 1 (c), thaum muaj cov pa roj hmab ntxiv, thiab cov roj muaj aqurous inhibits kev sib cais ntawm cov surfactant molecule hauv dej. Raws li cov nyhuv sib xyaw ua ke ntawm ob txoj kev sib xyaw ua ke, lub surfactant molecules yog enrice-kua interface thiab yauv ua kom muaj kev sib raug zoo, yog li txo cov nro dej. Tsis zoo li cov suractantal surfactants, gemini surfactants yog "dimers" uas tuaj yeem txo cov pab pawg txuas ntawm cov dej thiab roj / dej cuam tshuam kev nruj dua. Ib qho ntxiv, Gemini Surfactants muaj qis cov ntsiab lus pom zoo, cov dej ua kom zoo dua qub, ua npuas ncauj, ntub dej thiab cov tshuaj tua kab mob.
| Taw qhia ntawm Gemini Surfactants Nyob rau hauv 1991, cov tub rog thiab Littau [13] npaj thawj Bis-Alkyl saw Surfactant nrog kev sib txuas ntawm cov pawg sib txuas, thiab muaj npe "Gemini Surfactant". Nyob rau tib lub xyoo, Zana thiab 14] 1996, cov kws tshawb nrhiav generalized thiab tham txog saum npoo (ciam teb (daws teeb meem ntawm cov ntsej muag sib txawv thaum sib txuas nrog cov surfactants. Xyoo 2002, Zana Intrepigated muaj txiaj ntsig ntawm cov txiaj ntsig sib txawv ntawm cov kev sib sau ua a Tom qab ntawd, QIU li al [16] tsim txoj kev tshiab rau cov txheej txheem tshiab ntawm cov kab mob cetyl Gemini Surfactant synthesis. |
Kev tshawb fawb txog Gemini Surfactants hauv Suav teb tau pib lig; Xyoo 1999, Jianexi Zhao los ntawm Fuzhou University ua qhov kev tshuaj xyuas txawv teb chaws ntawm Gemini surfactants thiab nyiam cov xim ntawm ntau lub koom haum tshawb fawb hauv Suav teb. Tom qab ntawd, kev tshawb fawb txog Gemini Surfactants hauv Suav teb pib ua tiav thiab ua tiav cov txiv hmab txiv ntoo tau. Nyob rau hauv xyoo tas los no, cov kws tshawb nrhiav tau mob siab rau lawv tus kheej rau txoj kev txhim kho lub GEMINIn surfactants thiab kev kawm ntawm lawv cov khoom siv cuam tshuam ntawm lub cev. Nyob rau tib lub sijhawm, cov ntawv thov ntawm Gemini burfactants tau maj mam tsim nyob rau hauv lub teb ntawm kom tsis muaj menyuam, defoaming thiab feam inhibition, tshuaj tua dej qeeb thiab ntxuav. Raws li seb cov pab pawg hydrophilic hauv surfactant molecules tau them rau cov hauv qab no: cationic, noionic thiab amphoter gemini surfactants. Ntawm lawv, Cationic Gemini Dismini surfactants feem ntau xa mus rau cov pab pawg ntawm ammasium lossis cov roj ntsha li cas, cov roj ntsha li cas yog cov polyoxyethylene gemini surfactants.
1.1 Cationic Gemini Surfactants
Cationic Gemini Surfactants tuaj yeem tshem tawm cov cations nyob rau hauv aqueous kev daws, tsuas yog ammonium thiab Qoon ammonium ntsev Guamium ntsev Gemini ntsev Gemini Surfactants. Cationic Gemini Surfactants muaj zoo biodegradity, muaj peev xwm tshem tawm cov khoom muaj peev xwm, cov tshuaj lom neeg yooj yim, cov tshuaj tiv thaiv yooj yim thiab kev muag khoom.
Quas ammonium ntsev los raws li Gemini Surfactants feem ntau tau npaj los ntawm tertiary amines los ntawm alkylation cov tshuaj tiv thaiv. Muaj ob txoj kev tseem ceeb hluavtaws raws li hauv qab no: Ib qho yog kom quaromize dibromo-hloov alkanes thiab ib leeg ntev-saw alkyl ditethyl tertiary amines; Qhov tod yog kom quaternize 1-bromo-hloov mus ntev-n, n, n, n, n, n Txawm li cas los xij, dibromo-hloov alkanes yog kim kim dua thiab feem ntau ua synthesized los ntawm tus qauv thib ob, thiab cov kev tawm tsam cov kev tawm tsam tau qhia hauv daim duab 2.
1.2 anionic gemini surfactants
Anionic Gemini Surfactants tuaj yeem sib cais actions nyob rau cov ntsev aqueous, tsuas yog sulfonates, sulfate salts, carboxylates thiab ntsev ntsev hom gemini surfactants. Anionic Surfactants muaj cov khoom zoo dua xws li kev txiav txim siab, ua npuas ncauj, cov neeg sawv cev ua npuas dej, thiab cov neeg sawv cev ua npuas dej, sawv cev, emulsifiers thiab dispersants.
1.2.1 sulfonates
Sulfonate-based biosurfactants have the advantages of good water solubility, good wettability, good temperature and salt resistance, good detergency, and strong dispersing ability, and they are widely used as detergents, foaming agents, wetting agents, emulsifiers, and dispersants in petroleum, Textile kev lag luam, thiab siv tshuaj lom neeg txhua hnub vim yog lawv cov txheej txheem raw, cov txheej txheem ntau lawm, thiab tus nqi qis. Li et al synthesized ib qho ntawm cov dialkyl tshiab acid gemin surfactant (2cn-surfactant (2CHATIC amine thiab taurasatic li cov ntaub ntawv raw hauv kev sib tw peb-kauj ruam.
1.2.2 sulfate ntsev
Sulfate ester salts doublet surfactants have the advantages of ultra-low surface tension, high surface activity, good water solubility, wide source of raw materials and relatively simple synthesis. Nws tseem muaj kev ntxuav ua kom zoo thiab ua npuas ncauj, kev ua tau ruaj khov, thiab cov sulfate ntsev ua haujlwm yog nruab nrab lossis me ntsis alkaline hauv cov kua aqueous. Raws li muaj nyob hauv daim duab 3, Tshav Dong thiab Alyethylene Glycol raws li cov khoom siv rulfate los ntawm sulfate estere ntsev hom baryonic surfactant-ga12-S-12.
1.2.3 Carboxylic acid ntsev
Carboxylate-based gemini surfactants feem ntau, ntsuab, yooj yim feaper dispersion, muaj cov khoom siv hluav taws xob zoo thiab ntub dej, thiab siv dav hauv cov tshuaj, Textiles, tshuaj lom neeg thiab lwm thaj teb. Cov lus qhia txog cov pab pawg ntawm cov pab pawg hauv carboxylate tuaj yeem txhim kho moleculactability thiab kuj ua rau lawv ntub dej, emulsification, dispersion thiab tshem tawm cov khoom. Mei li al synkesized lub carboxylate-based baryonic pawg surfactant cgs-2 uas muaj cov dodecylamine, diromoolhane thiab succinic anhydride li cov ntaub ntawv raw.
1.2.4 Phosphate Salts
Phosphate Ester ntsev hlau hom gemini surbactants muaj cov qauv zoo sib xws rau cov qauv vaj tsiaj xws li thim rov qab Micelles thiab vesicles. Phosphate Ester ntsev hom gemini surgactants tau tau siv dav ua cov tshuaj tua kab mob thiab cov tshuaj tua kab mob qis tau ua rau lawv cov tshuaj tiv thaiv kev tu tawv nqaij. Qee yam tshuaj phosphate tuaj yeem ua anticancer, tshuaj tiv thaiv thiab cov tshuaj tua kab mob tau tsim. Phosphate Ester ntsev ntau hom rau cov tshuaj tua kab thiab tuaj yeem siv tsis tau tsuas yog cov tshuaj tua kabmob thiab cov tshuaj tua kab mob tab sis kuj yog tshuaj tua kab mob. Zheng et tau kawm cov synthesis ntawm phosphate ester ntsev Gemin-quat cov txiaj ntsig, thiab cov txheej txheem hluavtaws yooj yim dua, thiab cov khoom siv hluavthaiv yooj yim dua nrog cov mob sib txawv. Cov mis molecular ntawm cov poov tshuaj hauv poov piam ntsev baryonic surfactant yog qhia hauv daim duab 4.
1.3 tsis-ionic gemini surfactants
Tsis muaj lub Gemini Surfactants tsis tuaj yeem cuam tshuam hauv cov tshuaj aqueous thiab muaj nyob hauv molecular daim ntawv. Hom Baryonic Surfactant tau kawm tsawg heev, thiab muaj ib qho yog cov piam thaj thiab lwm tus yog dej cawv ether ether. Nonionic gemini surfactants tsis muaj nyob rau hauv ionic lub xeev hauv kev daws, yog qhov tsis yooj yim cuam tshuam nrog lwm hom surfactants, thiab muaj solubility zoo. Therefore, nonionic surfactants have various properties such as good detergency, dispersibility, emulsification, foaming, wettability, antistatic property and sterilization, and can be widely used in various aspects such as pesticides and coatings. Raws li pom hauv daim duab 5, nyob rau xyoo 2004, Fitzgerald thiab cov synthesized polyoxyethylene raws li gemini remfactants (cn-2h2o (ch2ch2o) mh (lossis gemhism).
02 physicochemical cov khoom ntawm Gemini Surfactants
2.1 kev ua si ntawm Gemini Surfactants
Txoj kev yooj yim tshaj plaws thiab tshaj plaws los ntsuas cov kev ua si saum npoo ntawm cov surfactants yog ntsuas qhov nro ntawm lawv cov kev daws teeb meem aqueous. Hauv txoj ntsiab cai, surfactants txo cov nro hauv kev daws teeb meem los ntawm kev taw qhia kev taw qhia nyob rau saum npoo (ciam av) dav hlau (daim duab 1 (c)). Qhov tseem ceeb ntawm lub tswv yim (CMC) ntawm Gemini Surfactants yog ntau dua ob qhov kev txiav txim siab me me thiab tus nqi C20 yog qhov qis dua li cov qauv qauv zoo sib xws nrog cov qauv qauv zoo sib xws. Cov baryonic surfactant molecule muaj ob pab pawg hydroughilic uas pab nws ua kom cov dej solubility zoo thaum muaj cov saw ntev ntev. Ntawm dej / cua interface, cov kev ua kom zoo nkauj yog xoob vim yog cov homogeneous tau txais txiaj ntsig zoo hauv cov lwg me me, yog li qaug zog rau lawv cov peev xwm txo cov dej. Nyob rau hauv kev sib piv, cov pawg txuas ntawm Gemini Surfactants yog qhov kev sib tw me me ntawm ob pawg hydrophilic yog kom qhov kev ncua deb ntawm cov haujlwm hydrothilic), ua rau muaj kev ua haujlwm zoo dua ntawm qhov saum npoo (ciam teb).
2.2 Sib Dhis Cov Qauv ntawm Gemini Surfactants
Nyob rau hauv cov kev daws teeb meem aqueous, raws li cov concenonic surfactant nce, uas nyob rau hauv lem lwm yam molecules mus rau sab hauv ntawm kev daws teeb meem rau daim ntawv mikelles. Qhov siab ntawm qhov twg ntawm surfactant pib ua micelles ua hu ua qhov tseem ceeb micelle concentration (cmc). Raws li muaj nyob hauv daim duab 9, tom qab lub siab yog ntau dua CMC, tsis zoo li kev sib sau ua ke ntawm Micrfactans, xws li ua ntau yam linhir, vim yog lawv cov qauv kev teeb tsa. Qhov sib txawv ntawm cov neeg fikelle loj, cov duab thiab hydration muaj qhov cuam tshuam ncaj qha rau theem kev daws teeb meem, thiab tseem coj rau kev hloov pauv ntawm Vis Accoelasticity. Cov surfactant, xws li anionic surfactants (SDS), feem ntau yog sau spherical micelles, uas muaj yuav luag tsis muaj kev cuam tshuam ntawm kev daws teeb meem. Txawm li cas los xij, tus qauv tshwj xeeb ntawm Gemini Surfactants ua rau kev tsim ntawm ntau cov nyom micphine sib txawv los ntawm cov ntawm cov kev sib piv ntawm cov surfactants. Lub viscosity ntawm awinous cov kev daws teeb meem nce nrog lub gemini surfactants, tej zaum vim tias cov ntawv tsim muaj tswv yim rau hauv lub vev xaib zoo li qauv. Txawm li cas los xij, cov kev daws teeb meem ntawm kev daws teeb meem tsawg dua nrog nce surfactant concentration, tej zaum vim muaj kev cuam tshuam ntawm lub vev xaib cov qauv.
03 antimicrobial cov yam ntxwv ntawm Gemini Surfactants
Raws li hom organic organic organic, cov antimicrobial mechanism ntawm cov pob txha ntawm tes thiab tshuaj tiv thaiv cell thiab tshuaj tiv thaiv ntawm tes, yog li rhuav tshem cov ntaub so ntswg microbial kom tiv thaiv lossis tua cov kab mob sib kis.
3.1 Antimicrobial cov yam ntxwv ntawm anionic gemini surfactants
Cov tshuaj tiv thaiv antimicrobial ntawm antimicrobial anionic surfactants yog tsuas yog txiav txim los ntawm qhov xwm ntawm cov antimicrobial lawv nqa. Hauv kev daws teeb meem zoo xws li cov txiv hmab txiv ntoo zoo nkauj thiab cov txheej txheem hydrophobic yuav khi rau ob-theem sib cuam tshuam rau hauv cov yeeb yaj kiab molecular ntom. Cov kab mob inibites pab pawg ntawm no cov txheej tiv thaiv tuab tiv thaiv no inhibit kev loj hlob ntawm cov kab mob.
Lub tshuab ntawm cov kab mob tseem ceeb ntawm anionic surfactants yog lub tswv yim txawv ntawm cov cationic surfactants. Cov txiv kab ntxwv inhibition ntawm anionic surfactants yog cuam tshuam rau lawv cov kev daws teeb meem thiab pawg inhibhabus tuaj yeem txwv. Hom semfactant yuav tsum tau muaj nyob ntawm cov qib txaus kom cov surfactant yog tam sim no nyob rau hauv txhua lub ces kaum ntawm lub system los tsim cov nyhuv microbicidal zoo. Nyob rau tib lub sijhawm, hom surfactant tsis muaj zos hauv zos thiab hom phiaj, uas tsis tsuas yog ua rau tsis tsim nyog tau khib nyiab ntev.
Raws li ib qho piv txwv, Alkyl sulfonate-based biosurfactants tau siv hauv cov tshuaj kho mob. Alkyl sulfonates, xws li Busulfan, feem ntau yog kho cov kab mob ntawm Guanine thiab cov kev ua yeeb yam los kho cov kab ke ntawm tes ua pov thawj, ua rau hauv lub tsev ntawm lub cev tuag.
3.2 Antimicrobial cov yam ntxwv ntawm Cationic Gemini Surfactants
Qhov tseem ceeb ntawm Cationic Gemini Surfactants tsim yog Quit Ammonium ntsev hom gemini surfactants. Quas ammonium hom cationic gemini surticans muaj ob hom hydrophobic surfactant nrog lub phab ntsa corysorption nrog lub xovtooj ntawm tes (peptidoglycan); Nyob rau tib lub sijhawm, lawv muaj ob lub npe tau them cov kab mob nitrogen, thiab delustrustant nkag rau hauv cov kab mob cell membrane siipid txheej, hloov lub permeability ntawm cell membrane, coj mus rau qhov sib xyaw ntawm cov kab mob, ntxiv rau Hydrophricic pawg sib sib zog nqus rau cov protein rau cov protein, ua rau poob ntawm enzyme kev ua si ntawm ob qho teebmeem no, ua rau fungicide, ua rau fungicide cov txiaj ntsig no muaj cov nyhuv muaj zog.
Txawm li cas los xij, los ntawm ib puag ncig pom, cov surfactants muaj hemolytic thiab chytooxicity, thiab lub sijhawm sib chwv ntev dua nrog cov dej muaj sia tuaj yeem nce lawv cov tshuaj lom.
3.3 Cov khoom siv tshuaj tua kab mob ntawm cov tsis muaj lub ntsej muag tsis muaj tseeb
Tam sim no ob hom kev tsis yog Gemini surfactants, ib qho yog cov piam thaj thiab lwm tus yog dej cawv ether ether.
Cov tshuaj tua kab mob tawm tsam ntawm cov suab thaj biosurfactants yog nyob ntawm modeculactants tuaj yeem khi rau ntawm cov xovtooj ntawm tes, uas muaj ntau ntawm phospholipids. Thaum cov concentration cov suab thaj surfacties mus txog ib qib ntawm cov khoom noj khoom haus thiab kev sib pauv ntawm cov txheej txheem thiab thaum kawg ua rau kev tuag ntawm lub tus kab mob.
Cov tshuaj tua kab mob ua haujlwm ntawm Phenolic thiab cov neeg sawv cev ntawm cov tshuaj tua kab mob ntawm phab ntsa lossis cov khoom siv hluav taws xob thiab cov kev cuam tshuam kev ua haujlwm metrerative. Piv txwv li, cov tshuaj tiv thaiv kab mob ntawm Diphenyl yog lawv txoj kev ua yeeb yam (phenols) yog cov kab mob cell thiab ua haujlwm ntawm lub xovtooj ntawm nucbrane thiab protein, txwv tus kev loj hlob thiab luam ntawm cov kab mob. Nws tseem paralyzes qhov metabolic thiab ua pa ua haujlwm ntawm cov enzymes nyob rau hauv cov kab mob hauv tus kab mob, uas ua tsis tau.
3.4 Cov yam ntxwv tua kabmob ntawm amphoteric Gemini Surfactants
Amphoter Gemini Surbactants yog chav kawm ntawm surfactants uas muaj ob lub nroog muaj cov qauv ntawm anionic hauv ib qho kev mob nruab nrab thiab cationic surfactants hauv lwm qhov xwm txheej. Cov txheej txheem ntawm cov kab mob amphoteric surfactans yog qhov tsis muaj kev cuam tshuam nrog cov kab mob tsis zoo thiab cuam tshuam nrog cov metabolism yooj yim.
3.4.1 Antimicrobial yam ntawm cov amino acid gemini surfactants
Amino acid hom baryonic surfactant yog cationic ampectiver bary farsonic surfactant muaj cai ntawm ammonium ntsev hom baryonic surfactant. Qhov zoo them ib feem ntawm surfactant yog nyiam qhov tsis zoo ntawm cov kab mob hluav taws xob, thiab tom qab ntawd cov kab mob hydrosatic, ua rau efflux ntawm cov ntsiab lus ntawm tes thiab cov lysis kom txog thaum tuag. Nws muaj qhov tseem ceeb tshaj plaws ntawm Qonmonium-based gemini surfactants: yooj yim hemolorants, thiab nws tau tsim rau nws cov ntawv thov raug nthuav dav.
3.4.2 Cov Tshuaj Tiv Thaiv Cov Hluav Taws Xob ntawm cov hom amino acid hom gemini surfactants
Qhov tsis-amino acider gemini survactants muaj cov npoo muaj ntau yam uas muaj ob qho tib si uas tsis tau lees paub thiab tsis zoo. Lub ntsiab tsis yog-amino acid hom gemini surin surfactants yog betaine, imidazoline, thiab amine oxide. Noj betaine hom ua piv txwv, biroter-hom amphater surnfactans muaj ob pab pawg, thiab cov antimicrobial mechanism ntawm cationic gemini surfactans yog Ua raws li hauv cov kua qaub thiab hais tias ntawm anionic gemini surfactants hauv kev daws teeb meem alkaline. Nws tseem muaj cov kev ua tau zoo zoo nrog lwm hom Surfactants.
04 Qhov Kawg thiab Outlook
Gemini surfactants yog siv tau nyob rau hauv lub neej vim yog lawv cov qauv tshwj xeeb, defoaming thiab ua npuas ncauj thiab ua npuas dej tso tawm thiab ntxuav tawm qeeb. Nrog rau kev siv nce ntxiv rau kev tiv thaiv ntsuab ib puag ncig, Gemini los yog maj mam tsim mus rau hauv ib puag ncig phooj ywg thiab ntau yam surfactants. Kev tshawb fawb yav tom ntej ntawm Gemini Surfactants tuaj yeem nqa tawm hauv cov hauv qab no thiab cov haujlwm tshiab ntxiv, tshwj xeeb tshaj yog dag zog rau cov tshuaj tiv thaiv thiab tshuaj tua kab mob; Sib cav nrog cov surfactants lossis additives ntxiv rau cov khoom lag luam nrog kev ua tau zoo; Thiab siv cov pheej yig thiab yooj yim muaj cov ntaub ntawv raw rau synthesize ib qho zoo phooj ywg gemini surfactants.
Lub Sijhawm Post: Mar-25-2022