Co esponding au ho : Adekunle Job
Copy igh © 2025 Au ho (s) e ain he copy igh o his a icle. This a icle is published unde he e ms o he C ea i e Commons A ibu ion Liscense 4.0.
Assessing he changes in mechanical p ope ies o di e en Gellan gum hyd ogels
unde issue enginee ing condi ions
Adekunle Job *
Depa men Technical Physics, Uni e si y o Eas e n Finland, Yliopis on an a 8, 70210, Kuopio Finland.
Wo ld Jou nal o Ad anced Resea ch and Re iews, 2025, 26(01), 4033-4048
Publica ion his o y: Recei ed on 12 Ma ch 2025; e ised on 26 Ap il 2025; accep ed on 29 Ap il 2025
A icle DOI: h ps://doi.o g/10.30574/wja .2025.26.1.1349
Abs ac
Backg ound: Tissue enginee ing (TE) seeks o de elop biological subs i u es ha es o e, main ain, o imp o e issue
unc ion. A signi ican challenge in TE is designing sca olds ha eplica e he biomechanical en i onmen o na i e
issues, especially in load-bea ing applica ions. Hyd ogels, pa icula ly Gellan Gum (GG), a e p omising sca old
ma e ials due o hei high wa e con en and unable iscoelas ic p ope ies. C osslinking agen s such as calcium (Ca²⁺)
and spe midine (SPD) play a c ucial ole in modula ing hese p ope ies.
Pu pose: This s udy aims o compa e he mechanical beha io o GG hyd ogels c osslinked wi h calcium and spe midine
o e a 28-day pe iod unde chond ogenic condi ions. The goal is o assess he impac o c osslinke ype on mechanical
s abili y and de e mine hei sui abili y as sca olds o ca ilage issue enginee ing.
Me hod: GG was dissol ed a a concen a ion o 5 mg/mL in HEPES/suc ose bu e and c osslinked using ei he 10 mM
CaCl₂ o 2 mM SPD. Polyme and c osslinke solu ions we e mixed a a 5:1 olume a io and cas in o cylind ical molds
(10 mm diame e , 2 mm heigh ). Hyd ogels we e cul u ed in chond ogenic media a 37°C and sampled on Days 1, 3, 7,
14, and 28. S ess elaxa ion es s we e conduc ed using a Mach-1 Mic omechanical Tes ing Sys em wi h a 3 mm la -
ended cylind ical inden e , applying 5%, 10%, and 15% comp ession s eps ollowed by 240-second holds.
Ins an aneous modulus (Eins ) and equilib ium modulus (Eeq) we e calcula ed using Hayes’ analy ical solu ion wi h
Poisson's a ios o 0.1 and 0.5, espec i ely. Da a we e s a is ically analyzed using Pea son co ela ion and ANOVA
(signi icance se a p < 0.05).
Resul s: Bo h GG/Ca and GG/SPD hyd ogels emained s uc u ally s able o e 28 days. GG/SPD ini ially exhibi ed a
sligh ly highe Eeq (0.0015 ± 0.0003 MPa) han GG/Ca (0.0014 ± 0.00009 MPa) on Day 1. Howe e , om Day 3 onwa ds,
GG/Ca hyd ogels consis en ly showed highe s i ness alues. O e ime, GG/Ca displayed a sligh inc ease in Eeq, while
GG/SPD emained unchanged o dec eased ma ginally. Simila ends we e obse ed o Eins . Pea son co ela ion
analysis indica ed a weak nega i e co ela ion be ween ime and Eeq in GG/SPD ( = -0.25), and a weak posi i e
co ela ion in GG/Ca ( = 0.08), nei he o which we e s a is ically signi ican . ANOVA e ealed no signi ican changes
in moduli o e ime o ei he g oup (p > 0.05).
Conclusion: GG hyd ogels c osslinked wi h calcium o spe midine exhibi s able mechanical p ope ies unde p olonged
chond ogenic cul u e. Al hough GG/Ca hyd ogels showed a sligh inc ease in s i ness o e ime, bo h o mula ions
main ained mechanical in eg i y and a e iable candida es o ca ilage issue enginee ing. Fu he s udies a e equi ed
o explo e hei biological pe o mance and egene a i e po en ial.
Keywo ds: Gallen Gum(GG); Hyd ogel; Spe midine(SPD); Calcium(Ca); C osslinke
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1. In oduc ion
Fo se e al yea s now, one o he mos signi ican a eas o medicine in he ecen decades has been lauded as Tissue
Enginee ing (TE) in he a ea o Regene a i e Medicine (RM). While he c ea ion o bio-enginee ed skin eplacemen s
was he p ima y ocus o he ini ial he apeu ically ele an TE s udies, Tissue Enginee ing applica ions ha e now been
p og essi ely b oadened o a wide spec um o issues and o gans. The eme gence o ei he mesenchymal adul s em-
cell echnology o emb yonic s em-cell echnology has inspi ed a ious a emp s o inco po a e his po en ial ool wi h
TE echniques and has uni ed he wo a eas unde he umb ella known as " egene a i e medicine." The iden i ica ion
o elocy es, a no el cell ype ha has been cha ac e ized in se e al o gans and iden i ied by elec on mic oscopy, opens
ano he doo way o RM and se es as a classic illus a ion o ansla ional medicine. In addi ion o cell- he apy
echniques, he use o gene he apy in conjunc ion wi h TE has been esea ched o p oduce issues and o gans. A i al
unc ion is also played by he ascula iza ion o cons uc ions in addi ion o he ma ix and cell eplacemen s. As a esul ,
new in i o models o ascula iza ion ha e eme ged ha enable axial ascula iza ion ollowed by cons uc
ansplan a ion. Tissue enginee ing has elemen s such as cells, sca old biomolecules, and bio eac o s [1–5].
The idea o using cell-cul u e me hods and bioma e ials o c ea e li ing issue equi alen s and/o o gans in he lab, la e
dubbed "Tissue Enginee ing," was i s p oposed as a mul idisciplina y app oach o egene a e los issue o o gan
unc ions. I was en isioned as he solu ion o bo h he o gan sho age in ansplan a ion medicine and he dono si e
mo bidi y issues ha had p e iously gone un esol ed. Clinicians and expe s om many di e en undamen al ields in
biology, enginee ing, and applied sciences ha e collabo a ed ex ensi ely only on he concep o g owing issue in he
lab. The e o e, in o de o c ea e biological eplacemen s ha will p ese e and es o e no mal unc ion in sick and
wounded issues, esea che s wo king in he ields o issue TE and RM a e cu en ly using he concep s o cell cul u e
and ansplan a ion, ma e ial science, and bioenginee ing.[6–10].
Though he e ha e been g ea e o s and imp o emen s in s anda dizing cell cul u e p ocesses and de eloping
cus omized bioma e ials o eplace los o gan unc ions, he ansla ion o labo a o y iumphs in o clinical si ua ions
has no p o en o be as success ul as i may be. This is pa ly due o he h ee-dimensional o ien a ion o he o gans and
issue, which necessi a es he exis ence o a mic o ascula ne wo k in o de o sus ain he su i al o he cells e en a
he cen e o any gi en cons uc by p o iding adequa e blood low and oxygena ion. Be o e ex insic ascula iza ion
may occu , an in e nal ascula ne wo k mus o m. This is an inhe en limi a ion on he abili y o cells o su i e in
h ee-dimensional sca olds in he i s s ages a e he implan a ion o issue-enginee ed subs i u es in o pa ien
s uc u es. [13].
1.1. Ins an aneous Modulus (Eins )
The ins an aneous modulus, o en ep esen ed as E, se es as an indica o o a ma e ial's s i ness a a speci ic poin
along i s s ess-s ain cu e, e lec ing he slope o he cu e a ha pa icula loca ion. Hooke's law desc ibes he s ess-
s ain ela ionship o an elas ic ma e ial as ollows:
σ=E⋅ε……………… (1.6)
He e:
-σ (sigma) signi ies he applied s ess o he ma e ial.
- (E) ep esen s he ins an aneous modulus.
- ε (epsilon) deno es he s ain (de o ma ion) expe ienced by he ma e ial.
The calcula ion o he ins an aneous modulus in ol es aking he de i a i e o he s ess-s ain cu e a he designa ed
poin , exp essed ma hema ically as: [116].
E=∆σ/ ∆ε ……………….(1.6.1)
The ini ial ins an aneous modulus (Eoins ) is de e mined a he in e sec ion o he i ed linea line, while he s ain-
dependen ins an aneous modulus (Eԑins ) is ob ained by measu ing he slope o his line a each s ess elaxa ion
phase [116]. The o e all ins an aneous modulus (Eins ) is hen gi en by he sum o Eoins and Eԑins :
Eins = Eԑins + Eoins ………………….(1.6.2)
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Figu e 1 The ins an aneous modulus de i ed om loading in se e al s eps. Each "poin " in he igh pic u e is o med
by he ed ising po ion in he le igu e [116]
1.2. Equilib ium Modulus (Eeq)
The equilib ium modulus, indica ed as Eeq, desc ibes he ma e ial's s i ness once i has a ained a s a e o mechanical
equilib ium, ypically ollowing some de o ma ion. I s compu a ion in ol es u ilizing s ess and s ain alues a a
speci ic poin and he o igin (uns essed s a e) [116].
The o mula o calcula ing he equilib ium modulus is as ollows:
Eeq=σ/ε ……………….(1.6.3)
Whe e:
- σ ep esen s he s ess a he poin whe e equilib ium is achie ed.
- ε s ands o he s ain a he poin whe e equilib ium is eached.
The equilib ium modulus o e s an a e age s i ness measu emen spanning om he o igin o he equilib ium poin ,
p o iding insigh in o he o e all s i ness o he ma e ial unde speci ic loading condi ions [116].
To cha ac e ize he equilib ium modulus, a common app oach in ol es employing mul i-s ep s ess elaxa ion o c eep
es s. Following he applica ion o displacemen s o s ess o he ma e ial, a elaxa ion pe iod is allowed. [116] The
equilib ium modulus is hen calcula ed using he s ess-s ain a io, de e mined by he slope o a linea line i ed o
equilib ium poin s, exp essed as:
Eeq=∆σeq/∆εeq ……………(1.6.4)
Figu e 2 Calcula ing he elas ic equilib ium modulus using s ess elaxa ion [116]
I 's impo an o no e ha he e ms "ins an aneous modulus" and "equilib ium modulus" a e equen ly employed
when dealing wi h linea elas ic ma e ials. Howe e , eal ma e ials can display mo e in ica e beha io s, including non-
linea i y, iscoelas ici y, o plas ici y, necessi a ing he use o mo e ad anced modeling and es ing app oaches.
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Addi ionally, i is c ucial o main ain consis ency in he uni s o s ess and s ain in hese o mulas, ypically using
Pascals (Pa) o s ess and dimensionless uni s o s ain since i ep esen s a a io o leng hs [116].
By calcula ing he a io o he di e ence be ween he peak s ess in he second s ep and he equilib ium s ess in he
i s s ep o he s ain ampli ude, he ins an aneous modulus was ound. By e alua ing he slope o he linea i a he
equilib ium loca ions, he equilib ium modulus was compu ed. The mean alues o s ess o he las i e seconds we e
used o app oxima e he equilib ium s esses o each s ep. Elas ic and iso opic beha io o he hyd ogel was
conside ed o bo h he immedia e and equilib ium loading phases. Thus, he Hayes model was used o modi y he
p edic ed ins an aneous and equilib ium moduli. I was assumed ha he ins an aneous and equilib ium moduli had a
Poisson's a io o 0.5 and 0.1 espec i ely [118]. In his p ojec wo k we made use o he same s ep me hod o calcula e
ou ins an aneous and equilib ium moduli howe e we de e mined ou ins an aneous and equilib ium moduli wi h
Poisson a io o 0.5
2. Ma e ials and Me hods
The ma e ials used o hyd ogel p epa a ion we e p o ided by P o . Kellomäki a he BioMediTech Ins i u e, Facul y o
Biomedical Sciences and Enginee ing, Tampe e Uni e si y o Technology. These ma e ials included s e ile- il e ed 5
mg/mL Gellan Gum (Gelzan™ CM Gel i e, Sigma-Ald ich) in a HEPES/suc ose solu ion (HEPES 25 mM, suc ose 100
mg/mL), spe midine ihyd ochlo ide in HEPES/suc ose bu e (2 mM), and calcium chlo ide (10 mM). Te lon molds
(10 mm diame e , 2 mm hickness) we e also u ilized.
Hyd ogels we e incuba ed in chond ogenic media, composed o α-Minimum Essen ial Medium, 1x Insulin-T ans e in-
Selenium +1, 0.3% Penicillin/S ep omycin, 50 μg/mL asco bic acid-2-phospha e, 55 μg/mL sodium py u a e, and 23
μg/mL L-p oline.
2.1. Hyd ogel P epa a ion
Two ypes o hyd ogels we e p epa ed: (1) Gellan Gum c osslinked wi h calcium (GG/Ca) and (2) Gellan Gum
c osslinked wi h spe midine (GG/SPD). Bo h hyd ogels we e p epa ed ollowing an iden ical p o ocol, main aining a
polyme - o-c osslinke olume a io o 5:1 (e.g., 1000 μL GG and 200 μL CL). Samples we e p epa ed in a 24-well pla e,
wi h 10 echnical eplica es pe pla e. The hyd ogels we e incuba ed a 37°C and moni o ed o e a 28-day pe iod, wi h
mechanical es ing conduc ed on days 1, 3, 7, 14, and 28.
2.2. Mixing Technique
Hyd ogel componen s we e combined and mixed in a glass ial be o e being ans e ed in o he molds. Addi ional
componen s we e inco po a ed in o he polyme solu ions be o e he addi ion o c osslinke s o ensu e homogenei y.
Once c osslinke s we e added, he solu ions we e b ie ly s i ed and ans e ed o he molds using a pipe e. The
gela ion onse occu ed wi hin 30 o 60 seconds. Following con i ma ion o gel o ma ion, 1 mL o chond ogenic media
was added unde asep ic condi ions. Media was e eshed e e y h ee days un il mechanical es ing.
Figu e 3 Schema ic ep esen a ion o hyd ogel-pla ed pla ing gel, ensu ing homogenous gela ion suppo ed by Te lon
a 37 °C. [117]
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2.3. Mechanical S udies
A Mach-1 (Mic omechanical Sys em, Biomomen um) biomechanical es ing de ice was employed o s ess elaxa ion
es ing. Da a ob ained om hese es s we e analyzed o de e mine he equilib ium modulus and ins an aneous
modulus o e ime. Each hyd ogel ype (GG/Ca and GG/SPD) was es ed using i e eplica es pe well pla e.
2.3.1. Mechanical Tes ing
Hyd ogel mechanical p ope ies we e assessed using a Mach-1 de ice comp ising a PM500-C P ecision Mo ion
Con olle (Newpo Co po a ion, USA), a Model V500Css Ac ua o (Newpo ), and a 0.15 kg single-axis load cell
(Biomomen um, Quebec, Canada). A cylind ical la -ended inden e (3 mm diame e ) was used o inden a ion es ing.
Figu e 4 (A ) Ac ua o , (B) Mo ion Con olle , (C) Inden e Raze , dia. 3mm
S ess elaxa ion es s we e conduc ed a oom empe a u e unde we condi ions. Samples we e e ie ed a
designa ed ime poin s (days 1, 3, 7, 14, and 28) and subjec ed o inden a ion es ing. The well pla es we e placed on
he Mach-1 de ice s age, and he inden e was aligned wi h each hyd ogel sample. Each sample unde wen a h ee-s ep
inden a ion p ocess, consis ing o 5% comp ession pe s ep, esul ing in a o al inden a ion o 15%, ollowed by a 240-
second elaxa ion pe iod pe s ep, yielding a o al es du a ion o 270 seconds pe sample. Fo ce and inden a ion dep h
da a we e con inuously eco ded and analyzed o de e mine ins an aneous and equilib ium modulus alues.
Figu e 5 Basic empla e o he biomechanics se up applica ion
2.4. S a is ical Analysis
Da a we e exp essed as mean ± s anda d de ia ion (SD). Each expe imen included i e eplica es pe sample g oup.
G oup di e ences we e analyzed using an Excel sp eadshee (R package 's a s' e sion 4.2.1), ollowed by - es s
(Tukey's es ) o mul iple compa isons. The Pea son co ela ion coe icien was employed o assess co ela ions
be ween modulus alues and ime. ANOVA was used o e alua e luc ua ions in modulus alues o e ime, wi h
s a is ical signi icance se a p < 0.05.
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Equilib ium modulus alues we e a e aged and compa ed be ween GG/SPD and GG/Ca samples o e ime o assess
s abili y, s i ness, and inden a ion esis ance. Fo example, equilib ium modulus alues (± SD) o GG/Ca we e 0.0014
± 0.00009 MPa on day 1 and 0.00137 ± 0.0002 MPa on day 7, which we e lowe han hose obse ed o GG/SPD (0.0015
± 0.0003 MPa on day 1 and 0.0014 ± 0.0002 MPa on day 7).
2.5. Expec ed Ou come
This s udy aims o p o ide undamen al insigh s in o he e olu ion o hyd ogel mechanical p ope ies o e he
incuba ion pe iod. The indings will con ibu e o a deepe unde s anding o hyd ogel beha io in long- e m cul u e,
in o ming u u e s udies conduc ed by he Biophysics o Bone and Ca ilage (BBC) esea ch g oup.
3. Resul s
3.1. Hyd ogel Appea ance and Dimensions
Hyd ogels we e p epa ed using molds wi h dimensions o 2 mm in hickness and 10 mm in diame e (Figu e 6). Figu e
6A p esen s a schema ic ep esen a ion o hyd ogel o ma ion in well pla es, while Figu e 6B illus a es he mold and
i s dimensions. Figu es 6C and 6D depic he hyd ogels wi hin he mold and a e emo al, espec i ely, ollowing
o e nigh incuba ion in cul u e media. The pink colo a ion o he gel esul ed om he p esence o phenol ed in he
cul u e medium.
Figu e 6 (A) Schema ic o gel o ma ion, (B) mold dimensions, (C) hyd ogel wi hin mold, (D) hyd ogel pos - emo al
e aining mold shape
3.2. Mechanical P ope ies o he Hyd ogels
Inden a ion es ing was conduc ed using he Mach-1 de ice o assess he mechanical p ope ies o he hyd ogels. A
mul i-s ep s ess elaxa ion p o ocol was applied, in which he inden e comp essed he hyd ogel samples wi hin a
con ined space. The applied o ce a each s ep is illus a ed in Figu e 7A. Typically, he equilib ium modulus o hyd ogels
is cha ac e ized using mul i-s ep s ess elaxa ion. Howe e , Figu e 7B depic s an in alid esul due o an abno mal
s ess elaxa ion pa e n, inconsis en wi h he expec ed h ee-s ep p o ocol alida ed in Figu es 8, 9, and 7A.
Consequen ly, only samples exhibi ing expec ed mechanical esponses we e included in u he analysis.
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Figu e 7 (A) Typical s ess elaxa ion esponse, (B) Abno mal s ess elaxa ion esponse (excluded om analysis)
3.2.1. Equilib ium Elas ic Modulus o he Hyd ogels O e he Incuba ion Pe iod
The equilib ium modulus alues (Table 1) indica e ha on Day 1, he modulus o GG c osslinked wi h spe midine
(GG/SPD) was sligh ly highe han ha o GG c osslinked wi h calcium (GG/Ca). By Day 3, he modulus o GG/Ca
exceeded ha o GG/SPD, bu his end was no sus ained, as GG/SPD exhibi ed a highe modulus on Day 7. F om Day
14 onwa d, GG/Ca demons a ed a consis en inc ease, su passing GG/SPD h ough Day 28.
Despi e hese a ia ions, s a is ical analysis e ealed no signi ican di e ence be ween he wo c osslinke s, as
indica ed by p- alues exceeding he 0.05 signi icance h eshold. This sugges s ha he obse ed di e ences in
equilib ium modulus be ween GG/SPD and GG/Ca a e no s a is ically signi ican and should no be conside ed
conclusi e.
Table 1 Equilib ium Modulus (MPa) o GG/Ca and GG/SPD (A e aged)
Equilib ium Modulus(MPa)
Ca
SPD
Time (Days)
Mean (µ)
±S d
Mean (µ)
± S d
Di e ence
P alue
1
0,00142534
9,07142E-05
0,001493667
0,000261774
-0,000068327
0,63508484
3
0,001440113
0,000189421
0,00143656
0,000193493
3,5528E-06
0,979707445
7
0,001378935
0,000170837
0,001412426
0,00028787
-3,3491E-05
0,846391846
14
0,001481232
0,000133703
0,001402372
0,000257827
7,88602E-05
0,601893198
28
0,001452707
0,000241861
0,001300737
0,000121923
0,00015197
0,294345953
The plo below, Fig.8, p ac ically e ealed how he a ious c osslinked hyd ogel changes h ough he ime o incuba ion
and he applica ion o inden a ion comp ession ha is om day 1,3,7,14 and 28 espec i ely. In o de o u he bu ess
o p o e i he e is signi ican di e ence be ween he alues eco ded wi h bo h c osslinke s on GG, we ook a s ep
u he o elabo a e his by looking a he Pea son co ela ion coe icien ( ), whe e we no iced a dec ease in equilib ium
o GG/SPD wi h ime and no change o hose c osslinked wi h GG/Ca wi h o -0.25 and 0.0837, espec i ely, which
indica e ha he e is low posi i e nega i e co ela ion be ween hem, we know ha Pea son coe icien helps o quan i y
a co ela ion, and o show he signi icance, we now looked a ha he P alues which a e p 0.6907 o GG/Ca and p 0.228
o GG/SPD which a e bo h highe han 0.05, shows ha he co ela ion is no s a is ically signi ican as con i med by
hei P alues. Howe e we de i ed he Pea son co ela ion and i s P alue om he aw da a which was plo ed (sca e
plo ) agains he independen a iable which a e he days. Remembe ha P alue helps o assess whe he a co ela ion
is eal, meaning " " and he P alue should be analyzed oge he no indi idually Fig.9 [120].
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Figu e 8 Equilib ium modulus (MPa) o c osslinked GG/Ca and GG/SPD Vs ime
Figu e 9 E alua ing Gel's Equilib ium Modulus Changes O e Time Using Pea son Co ela ion
In Table 1, we p e iously desc ibed he beha io o hyd ogels GG/Ca and GG/SPD a a 5:1 a io o e he cou se o he
incuba ion pe iod unde an inden a ion mechanical comp ession p o ocol. The da a e ealed luc ua ions in he
modulus alues ac oss he days, wi h no able excep ions on days 14 and 28, whe e he GG/Ca hyd ogel consis en ly
exhibi ed highe alues. Figu e 12 u he illus a es he ela ionship be ween he a ious hyd ogels (GG/Ca and
GG/SPD) ac oss he incuba ion days. To p o ide a clea e unde s anding o hese ends, we applied Pea son's
co ela ion coe icien and i s co esponding p- alue o assess he ela ionship and s a is ical signi icance. Howe e , ou
analysis showed ha he obse ed co ela ion was no s a is ically signi ican .
Fu he mo e, box plo s we e gene a ed (Fig. 10 and Fig. 11) o each o he hyd ogels, GG/Ca and GG/SPD, o u he
illus a e hei ela ionship o e ime using he aw da a. These box plo s indica e ha he da a did no ollow a clea
end ela i e o he du a ion o he incuba ion pe iod.
To p o ide a mo e igo ous analysis, we pe o med an analysis o a iance (ANOVA) on he da a o each hyd ogel,
c osslinked wi h he same c osslinke , as shown in Fig. 10 (GG/Ca) and Fig. 11 (GG/SPD). This was done o assess
whe he he luc ua ions obse ed in he da a held s a is ical signi icance, as discussed in pa ag aph 1 o sec ion 3.2.1.
The ANOVA esul s e ealed ha he luc ua ions we e no s a is ically signi ican , sugges ing ha he modulus does
no show consis en inc eases o dec eases o e ime. Speci ically, he P- alues o GG/Ca (0.940) and GG/SPD (0.831)
we e bo h g ea e han 0.05, indica ing no signi ican luc ua ions in he da a o ei he hyd ogel.
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Figu e 10 Compa ison o equilib ium modulus(MPa) o GG/Ca changes ac oss he days
Figu e 11 Compa ison o equilib ium modulus(MPa) o GG/SPD changes ac oss he days
4. Discussion
Ce ain ino ganic and biological amine ca ions a e known o c osslink nega i ely cha ged polyme s, o ming physical
hyd ogels ia iono opic gela ion [115]. In his s udy, we employed spe midine, an endogenous polyamine, and calcium,
an ino ganic ca ion, as c osslinke s o Gellan Gum (GG) hyd ogels. While hyd ogels can be o med by simply adding a
c osslinke o GG, we also incuba ed he hyd ogel in chond ogenic media. Al hough no pa o ou expe imen , o he
s udies ha e included a ious biological molecules in hyd ogels, and GG has shown p omise in issue enginee ing (TE)
applica ions. The me hod used he e o p epa ing GG c osslinked wi h Ca and SPD is lexible, p ac ical, and cos -
e ec i e.
GG is FDA- and EMA-app o ed as a gelling agen in ood, cosme ics, and pha maceu icals, and i s use in TE has yielded
encou aging esul s. Hyd ogels a e ca ego ized in o weak gels, which low unde s ess, and ue gels, which ac u e
and become sel -suppo ing unde se e e s ess. Ou hyd ogels a e conside ed ue gels, main aining hei s uc u e
e en when handled wi h weeze s o cas [109].
We e alua ed he mechanical p ope ies o he hyd ogels unde cul u ed condi ions. Al hough all ma e ials we e based
on GG, we assessed he elas ic beha io o he c osslinke s (Ca and SPD) using s ess elaxa ion es s, de e mining he
Wo ld Jou nal o Ad anced Resea ch and Re iews, 2025, 26(01), 4033-4048
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