Development and evaluation of new methods for protein quantification in dissolving microneedles formulations

Area of Science:

• Pharmaceutical Sciences
• Biotechnology
• Analytical Chemistry

Background:

• Dissolving microneedles (DMNs) offer painless transdermal delivery of protein drugs.
• Accurate quantification of encapsulated proteins is essential for DMN formulation quality control.
• The classic BCA assay (c-BCA) is hindered by dextran interference, leading to inaccurate ovalbumin (OVA) quantification.

Purpose of the Study:

• To develop and validate new methods for accurate protein quantification in DMNs.
• To address the interference issues of dextran (Dex) in protein assays.
• To compare the performance of modified BCA (m-BCA) and RP-HPLC with c-BCA for DMN formulations.

Main Methods:

• Development of a modified BCA (m-BCA) assay.
• Implementation of reversed-phase HPLC (RP-HPLC) for protein analysis.
• Validation of m-BCA and RP-HPLC using ovalbumin (OVA) in DMN formulations.

Main Results:

• Both m-BCA and RP-HPLC demonstrated reliable protein quantification in DMNs.
• Methods showed excellent linearity (correlation coefficients >0.99).
• High accuracy (100 ± 10% recovery) and precision (<10% RSD) were achieved for inter-day measurements.

Conclusions:

• Modified BCA and RP-HPLC are suitable for accurate protein quantification in DMNs.
• These methods overcome dextran interference affecting traditional assays.
• The validated methods enable rapid and reliable assessment of protein-loaded DMNs for transdermal delivery.