Related Experiment Videos
Methyl-DEAE-dextran: a candidate biomaterial
Ylenia Zambito1, Andrea Baggiani, Vera Carelli
1Department of Bioorganic Chemistry and Biopharmaceutics, University of Pisa, Pisa, Italy. zambito@farm.unipi.it
Bio-Medical Materials and Engineering
|October 9, 2004
Summary
Researchers successfully quaternized DEAE-dextran, creating a novel methyl ester (Me-DEAE-dextran) salt with N-acetylcysteine. This new formulation shows improved drug loading and lower viscosity for ophthalmic applications like dry eye treatment.
Area of Science:
- Polymer Chemistry
- Ophthalmology
- Drug Delivery
Background:
- DEAE-dextran is a widely used polymer.
- Current ophthalmic formulations for dry eye can be hypertonic and irritant.
- N-acetylcysteine (AcCy) is a therapeutic agent for dry eye.
Purpose of the Study:
- To achieve complete quaternisation of DEAE-dextran.
- To develop a novel ophthalmic formulation for dry eye treatment using quaternised DEAE-dextran.
- To compare the properties of the new formulation with existing ones.
Main Methods:
- DEAE-dextran was reacted with iodomethane and NaOH, followed by dialysis for purification.
- Alkalimetry confirmed complete quaternisation.
- N-acetylcysteine (AcCy) was formulated with the quaternised polymer (Me-DEAE-dextran/AcCy) and compared to a non-quaternised control (DEAE-dextran/AcCy).
Main Results:
- Complete quaternisation of DEAE-dextran was achieved, confirmed by the absence of amino groups.
- The Me-DEAE-dextran/AcCy formulation exhibited higher AcCy content (23% vs 13%) compared to the control.
- Solutions of Me-DEAE-dextran/AcCy showed lower viscosity (20.5 mPa s vs 23.9 mPa s) and were isotonic (245 mOsm/kg), unlike the hypertonic commercial product.
Conclusions:
- Complete quaternisation of DEAE-dextran is feasible.
- The novel Me-DEAE-dextran/AcCy formulation offers enhanced drug loading and improved physical properties (lower viscosity, isotonicity) for ophthalmic use.
- This quaternised polymer represents a promising candidate for developing more comfortable and effective treatments for dry eye syndrome.