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RPL Peptide

Official Technical Documentation

Stability Guide


Stability Guide — Tirzepatide

Stability Summary

Form Storage Condition Stability Period
Lyophilized -20°C 2+ years
Lyophilized 2–8°C 12 months
Lyophilized 25°C (Room Temp) 30 days
Reconstituted 2–8°C 30 days
Reconstituted 25°C 7 days
Reconstituted (Aliquoted) -20°C 6 months

Stability Testing Parameters

Stability is monitored using the following analytical methods:

Test Method Frequency
Appearance Visual inspection Each time point
Purity HPLC (214 nm) Each time point
Identity LC-MS Initial and final time points
pH pH meter Each time point
Water Content Karl Fischer Initial only
Endotoxin LAL Initial only

Accelerated Stability Data

Condition Duration Expected Purity Retention
40°C / 75% RH 2 weeks ≥98%
40°C / 75% RH 4 weeks ≥97%
25°C / 60% RH 3 months ≥98%
25°C / 60% RH 6 months ≥97%

Degradation Pathways

Pathway Risk Mitigation
Hydrolysis Medium Keep dry; low moisture content
Oxidation Low-Medium Protect from air; inert atmosphere
Deamidation Low Maintain pH 4.0–6.5
Aggregation Low Avoid vigorous shaking; proper reconstitution
Microbial Growth Medium (reconstituted) Use bacteriostatic water; sterile technique

Stability Testing Protocol

Real-Time Stability

  • Storage: -20°C and 2–8°C
  • Time Points: 0, 1, 3, 6, 12, 18, 24 months
  • Samples: Triplicate vials per time point
  • Testing: Appearance, purity (HPLC), identity (LC-MS), pH, moisture

Accelerated Stability

  • Storage: 25°C/60% RH and 40°C/75% RH
  • Time Points: 0, 2, 4, 8, 12 weeks
  • Samples: Triplicate vials per time point
  • Testing: Appearance, purity (HPLC), pH

Freeze-Thaw Stability

Freeze-Thaw Cycles Purity Retention
1 cycle ≥99%
3 cycles ≥98%
5 cycles ≥97%
10 cycles ≥95%

Note: Repeated freeze-thaw cycles are not recommended. Aliquot reconstituted peptide for single-use applications.

Handling Effects on Stability

Condition Effect on Stability Recommendation
Light exposure Moderate degradation Store in dark; use amber vials
Temperature spikes Accelerated degradation Maintain cold chain
Vortexing Potential aggregation Swirl gently only
Dilution in buffers Generally stable Use recommended buffers
Metal ion contact Potential chelation Use low-binding labware

Stability Indicators

Indicator Sign of Degradation
Visual Discoloration, cloudiness, precipitation
HPLC Decreased main peak area; new impurity peaks
pH Significant pH shift (>1.0 unit)
Bioactivity Reduced receptor binding (functional assay)

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Official Technical Documentation

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