Unveiling the potential of microsponges: Enhancing oral bioavailability


Oral medication administration is widely recognized as the most practical and widely used method. Medications with a short half-life and easy absorption in the gastrointestinal tract are quickly removed by the bloodstream. To avoid these issues, oral controlled-release formulations have been created. There are a ton of novel formulation approaches in the realm of medication delivery systems. One new novel approach that is becoming increasingly well-liked these days is the usage of microsponges. A wide variety of active chemicals can be entrapped by the highly cross-linked, porous, polymeric structure that makes up the Microsponges Delivery System (MDS). Various polymers like ethyl cellulose, polystyrene, etc., have been utilized in forming microsponges and these active microsponges can be incorporated into formulations, such as capsules, gel, and powders, and have a broad package of benefits. The microsponges have satisfactory stability over pH values ranging from 1 to 11, they exhibit reasonable stability at temperatures as high as 130, and entrapment efficiency is great, reaching 50–60%. The preparation of microsponges involves the Quasi-emulsion solvent method, and the emulsion solvent diffusion method the release of drug through microsponges increases with increasing drug-polymer ratio and lowering polymer wall thickness. The microsponges are characterized for visual characterization, zeta potential, entrapment efficiency, and drug content. This review is focused on their advantages over other dosage forms, methods of preparation, characterization, and application of microsponges.


Microsponges are porous, non-collapsible, highly cross-linked polymeric microspheres microsponges with a particle
size range of 5 to 300 μm. They can absorb a broad variety of active substances and release them gradually.
Microsponges’ sponge-like texture gives them special dissolving and compression characteristics. They have little
negative effects and increase patient compliance. They are also very stable, non-toxic, non-allergic, non-mutagenic, and extremely effective. Microsponges made of a variety of polymers, including PHEMA, ethyl cellulose, polystyrene, and Eudragit RS100, have been used. Moreover, these active microsponges offer a wide range of advantages and can be added to formulations including capsules, gel, and powders. Microsponges have shown promise in the fields of
cosmetics and pharmaceuticals. Examples of their applications include antifungal vaginal gel, enhanced arthritis
therapy, burn wound treatment using silver sulfadiazine-loaded microsponge gel, gastro retentive delivery, matrix
tablets, and colon-specific drug delivery systems.

Patented polymeric delivery systems called microsponges are made of porous microspheres that can hold a variety of
active substances, including sunscreens, emollients, perfumes, essential oils, and anti-infective, anti-fungal, and antiinflammatory compounds. Each microsphere has a huge porous surface area and is made up of numerous
interconnected voids within a non-collapsible structure, much like a real sponge. Won invented the microsponge
technique in 1987, and Advanced Polymer Systems was given the original patents.

Currently, Cardinal Health, Inc. holds a license to utilize this intriguing technology for topical products. Depending on
the level of smoothness or after-feel needed for the final recipe, the microsponges’ diameter can range from 5 to 300
μm. A typical 25 μm sphere can have up to 250000 holes and an internal pore structure similar to 10 feet in length,
meaning that even though the microsponge size may vary, the total pore volume will be approximately 1 ml/g. As a
result, each microsponge develops a sizable reservoir that can hold up to its own weight’s worth of active agent. These
microsponge materials are made safer by the fact that the microsponge particles themselves are too big to penetrate
the skin. The possibility of bacterial contamination of the materials trapped in the microsponge is another issue related
to safety. Because the pore width is smaller, bacteria with a size range of 0.007 to 0.2 μm cannot enter the microsponges’ tunnel structure.

Download the full article as PDF here: Unveiling the potential of microsponges

or read it here

Vidya K P, E. Gopinath, Ganesh N. S, J Adlin Jino Nesalin and Vineeth Chandy, Unveiling the potential of microsponges: Enhancing oral bioavailability, World Journal of Biology Pharmacy and Health Sciences, 2024, 17(02), 405–414. Article DOI: 10.30574/wjbphs.2024.17.2.0085, DOI url: https://doi.org/10.30574/wjbphs.2024.17.2.0085, Received on 12 January 2024; revised on 20 February 2024; accepted on 23 February 2024

CPHI & PMEC China will be held at 19-21 June 2024. Register for free:


CPhI China 2024

You might also like