Author(s):
Jyoti Kumari, Madhuri Kowaich, Anju Mishra, Sita Ahirwar
Email(s):
anishchead@gmail.com
DOI:
10.52711/0975-4377.2026.00052 
Address:
Jyoti Kumari1, Madhuri Kowaich1, Anju Mishra2, Sita Ahirwar2
1Students, School of Pharmacy, Chouksey Engineering College, Bilaspur (CG) India.
2Assistant Professor, School of Pharmacy, Chouksey Engineering College, Bilaspur (CG), India.
*Corresponding Author
Published In:
Volume - 18,
Issue - 4,
Year - 2026
ABSTRACT:
Antiviral microspheres have emerged as multi-purpose platforms to overcome major disadvantages of traditional antiviral therapy such as short half-life, low bioavailability and frequent dosing. This review summarizes the existing evidence on formulation approaches, polymers, evaluation techniques and the key design parameters affecting the performance of antiviral microspheres via oral, ocular, parenteral and mucosal routes. Poly (lactic acid) (PLA) and poly (lactic-co-glycolic acid) (PLGA) are synthetic biodegradable polymers that are widely used to formulate long-acting depots in which particle size, drug loading and degradation-controlled release are determined by polymer composition, molecular weight and processing conditions. Natural and modified polymers such as chitosan, thiolated chitosan and alginate provide mucoadhesive and pH responsive systems that enhance the residence time and control release at mucosal and ocular surfaces. Emulsion–solvent evaporation, ionic gelation, spray drying, and emerging microfluidic approaches provide a combination of fine control over microsphere size and architecture that modulates entrapment efficiency and biphasic release profiles desired for rapid onset followed by sustained antiviral exposure. The assessment has progressed from conventional physicochemical characterization (size, morphology, zeta potential, entrapment efficiency, in vitro release) to route-specific biopharmaceutical and antiviral evaluation (mucoadhesion, ex vivo permeation, pharmacokinetics and in vivo efficacy). These studies show that appropriately designed microspheres can increase gastric or ocular residence, increase systemic exposure after intramuscular or subcutaneous injection and improve local antiviral action at mucosal sites. However, heterogeneity in in vitro release conditions, mucosal models and antiviral assays limits comparability between studies and restricts the development of generalizable design rules. The review highlights polymer properties, drug-polymer interactions and process parameters as critical determinants of successful antiviral microsphere design, while pointing to gaps in systematic, Quality-by-Design (QbD) studies that link these variables to clinically relevant antiviral outcomes. In future work, to fully exploit the potential of microsphere technologies for existing and new antiviral agents, standardized testing protocols, mechanistic modeling and direct comparisons with alternative delivery systems should be emphasized.
Cite this article:
Jyoti Kumari, Madhuri Kowaich, Anju Mishra, Sita Ahirwar. A Review on Formulation and Evaluation of Microspheres of Antiviral Drugs. Research Journal of Pharmaceutical Dosage Forms and Technology. 2026; 18(4):377-2. doi: 10.52711/0975-4377.2026.00052
Cite(Electronic):
Jyoti Kumari, Madhuri Kowaich, Anju Mishra, Sita Ahirwar. A Review on Formulation and Evaluation of Microspheres of Antiviral Drugs. Research Journal of Pharmaceutical Dosage Forms and Technology. 2026; 18(4):377-2. doi: 10.52711/0975-4377.2026.00052 Available on: https://www.rjpdft.com/AbstractView.aspx?PID=2026-18-4-14
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