Abstract:

To study the stabilities of recombinant human keratinocytegrowth factor-2(rhKGF-2) deposited at different conditions,and elucidate the influences of temperature,pH,buffer solutions and repeated freeze thawing on rhKGF-2 stability.Methods rhKGF-2 was deposited at different conditions such as temperatures (－20℃,4℃,25℃,40℃),pH(pH 4－9),buffer solutions(Citrate buffer solution,Disodium hydrogen phosphate-Citrate buffer,Phosphate buffer,Jifeishi buffer) and repeated freeze thawing, respectively.The purity of rhKGF-2 was determined by RP-HPLC,and the appearance was also observed.Results All properties of rhKGF-2 were not altered during the observation period at －20℃ and 4℃;the purity of rhKGF-2  deposied for 28 d was reduced to (68.20±0.14)% compared with 0 h(100.00%)  at 25℃;the purity of rhKGF-2  deposited for 9 h was reduced to (4.80±0.39)% compared with 0 h(100.00%)  at 40℃. The purity of rhKGF-2(pH 6.0) deposited for 90 d was  reduced to(79.20±0.12)% compared with 0 h(100.00%) at 25℃(P<0.05);the purities of rhKGF-2(pH 4.0,9.0) deposited for 120 h were respectively reduced to (15.60±0.3)% and (67.30±0.1)% compared with 0 h(100.00%)at 25℃(P<0.01).The purity of rhKGF-2(pH6.0) deposited in Citrate  buffer solution deposited for 60 d  was  reduced to (79.20±0.15)% compared with 0 h(100.00%)  at 25℃(P<0.01).The purity of rhKGF-2 had no significant change  after repeated freeze thawing(P>0.05).Conclusion rhKGF-2 is stable when deposited at low temperature and pH6.0－7.0 neutral conditions.High temperature,acidic and basic conditions are harmful for rhKGF-2 stability.It is profit for rhKGF-2 stability in Citrate buffer solution.There is no impact on rhKGF-2 stability after repeated freeze thawing.

Key words: recombinant human keratinocyte growth factor-2;purity;stability