A Review on Microspheres as a Novel Controlled Drug Delivery System

Abstract

Over the past three decades, controlled drug delivery systems have become more developed and play a key role in pharmaceuticals formulations. There are many shortcomings in Traditional or Conventional drug delivery systems like for maintaining desired therapeutic drug plasma concentration there is a need for frequent dosing for particular drugs having shorter half-lives. Furthermore, because of frequent dosing requirement, there is poor patient compliance which causes fluctuation in plasma concentration of the drug. The limitations of conventional drug delivery can be overcome by the development of novel drug delivery systems, of which the controlled drug delivery can maintain constant drug plasma concentration by slowly releasing the drug over an extended period. Developing controlled drug delivery systems can also improve the systemic bioavailability of the drug, thus enhancing the therapeutic efficacy of the drug and better patient compliance. There are many different approaches for such controlled delivery systems such as liposomes, niosomes, ethosomes, phytosomes, microemulsion, and microspheres. Among all the approaches microspheres are more convenient as the drug is slowly released from the polymeric matrix and the polymers used are mostly biodegradable and possess no side effects. Therefore, microspheres can be used in various medicinal departments such as oncology, gynecology, radiology, pulmonary, cardiology, diabetes, and vaccine therapy. This review article focuses on recent different types of microspheres along with their methods of preparation. The microspheres formulated can be later evaluated and characterized by different procedures.

Formulation and Evaluation of Ciprofloxacin Microspheres Designed by Using Natural Polymers by Ionic Gelation Technique

“…Upon coming into contact with the cross-linking agent, this was permitted to operate in a matrix. After the CaCl2 had expired, it was decanted and the resulting microspheres were cleaned and dried [4,5]. Similar to this, several formulations (F1-F8) were created and the desired formulation F4 among them, was assessed.…”

Modeling of in vitro drug release from polymeric microparticle carriers

“…The properties of the polymer significantly affect the site, mechanism and kinetics of drug release from the carrier. Two main mechanisms of drug release from the microspheres have been described: (a) the drug's diffusion and/or dissolution from the swellable or non-swellable polymer matrix, and (b) the drug's diffusion and/or dissolution governed by the erosion or dissolution of the polymer (22)(23)(24)(25)(26). The release of the drug substance from the biodegradable microspheres is a consequence of the gradual decomposition (bioerosion) of the polymer matrix, typically by hydrolysis or enzymatic degradation.…”

A Technical Note: on Microspheres

“…It can be used in a variety of ways, including subcutaneous or intratumoral injection and transpulmonary administration as an inhalant [3]. More than 90% of available painkillers are administered by oral administration, which is the most popular and easiest route [4]. However, oral administration always has limited clinical efficacy due to the need for frequent administration to achieve stable plasma concentrations and patient compliance is not good.…”