Background:
With the advancement in the field of medical science, the idea of sustained release of the
therapeutic agents in the patient’s body has remained a major thrust for developing advanced drug delivery systems
(DDSs). The critical requirement for fabricating these DDSs is to facilitate the delivery of their cargos in a
spatio-temporal and pharmacokinetically-controlled manner. Albeit the synthetic polymer-based DDSs normally
address the above-mentioned conditions, their potential cytotoxicity and high cost have ultimately constrained
their success. Consequently, the utilization of natural polymers for the fabrication of tunable DDSs owing to their
biocompatible, biodegradable, and non-toxic nature can be regarded as a significant stride in the field of drug
delivery. Marine environment serves as an untapped resource of varied range of materials such as polysaccharides,
which can easily be utilized for developing various DDSs.
Methods:
Carrageenans are the sulfated polysaccharides that are extracted from the cell wall of red seaweeds.
They exhibit an assimilation of various biological activities such as anti-thrombotic, anti-viral, anticancer, and
immunomodulatory properties. The main aim of the presented review is threefold. The first one is to describe the
unique physicochemical properties and structural composition of different types of carrageenans. The second is to
illustrate the preparation methods of the different carrageenan-based macro- and micro-dimensional DDSs like
hydrogels, microparticles, and microspheres respectively. Fabrication techniques of some advanced DDSs such as
floating hydrogels, aerogels, and 3-D printed hydrogels have also been discussed in this review. Next, considerable
attention has been paid to list down the recent applications of carrageenan-based polymeric architectures in
the field of drug delivery.
Results:
Presence of structural variations among the different carrageenan types helps in regulating their temperature
and ion-dependent sol-to-gel transition behavior. The constraint of low mechanical strength of reversible gels
can be easily eradicated using chemical crosslinking techniques. Carrageenan based-microdimesional DDSs (e.g.
microspheres, microparticles) can be utilized for easy and controlled drug administration. Moreover, carrageenans
can be fabricated as 3-D printed hydrogels, floating hydrogels, and aerogels for controlled drug delivery applications.
Conclusion:
In order to address the problems associated with many of the available DDSs, carrageenans are
establishing their worth recently as potential drug carriers owing to their varied range of properties. Different
architectures of carrageenans are currently being explored as advanced DDSs. In the near future, translation of
carrageenan-based advanced DDSs in the clinical applications seems inevitable.
Poloxamer-based in situ gelling thermoresponsive systems for ocular drug delivery applications
