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Facile Protocol for the Synthesis of Self-assembling Polyamine-based Peptide Amphiphiles PPAs and Related Biomaterials

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[Stabilized thiomer PAA-Cys-6MNA].

Jian-Sheng Yang, Xian-Hui Chen, Hua Zhang

Yao Xue Xue Bao = Acta Pharmaceutica Sinica

|September 13, 2014

Summary

Stabilized thiomers, poly(acrylic acid)-cysteine-6-mercaptonicotinic acid (PAA-Cys-6MNA), maintain permeation enhancement and improve stability compared to traditional thiomers. These novel polymers show potential for drug delivery applications.

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Area of Science:

Polymer Chemistry
Biomaterials Science
Drug Delivery

Background:

Traditional thiomers exhibit poor stability, limiting their application in drug delivery.
Developing stabilized thiomers is crucial for enhancing drug permeation and therapeutic efficacy.

Purpose of the Study:

To synthesize and characterize stabilized thiomers, specifically poly(acrylic acid)-cysteine-6-mercaptonicotinic acid (PAA-Cys-6MNA).
To evaluate the permeation enhancement and stability of the synthesized stabilized thiomers.
To investigate the mechanism underlying the permeation enhancement effect.

Main Methods:

Synthesis of poly(acrylic acid)-cysteine (PAA-Cys) and PAA-Cys-6MNA via conjugation and grafting.
Quantification of free thiol groups and coupled 6-mercaptonicotinic acid (6MNA).
Permeation studies using Franz diffusion cells with fluorescein isothiocyanate dextran (FD4) as a model drug.
Confocal laser scanning microscopy to assess the influence on Caco-2 cell tight junctions.

Main Results:

Both PAA-Cys and PAA-Cys-6MNA promoted FD4 permeation across rat intestine.
PAA-Cys-6MNA demonstrated enhanced stability, unaffected by pH or air oxidation.
The polymers influenced the distribution of F-actin, a tight junction protein, in Caco-2 cells.

Conclusions:

Stabilized thiomers (PAA-Cys-6MNA) effectively maintain permeation enhancement while exhibiting improved stability over traditional thiomers (PAA-Cys).
The mechanism of permeation enhancement is potentially linked to the polymers' interaction with cellular tight junction proteins.