Polymer Composite-Assisted Crystal Engineering for Drug Synthesis and Property Control through Solid Solutions and Co-Crystals

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Year : 2026 | Volume : 14 | 03 | Page :
    By

    Sandeep P Shewale,

  • Dipti Y Sakhare,

  1. Associate Professor, Department of Chemical Engineering, MIT Academy of Engineering Alandi (D), Pune, Maharashtra, India
  2. Professor, Department of Electronics and Telecommunication, MIT Academy of Engineering Alandi (D), Pune, Maharashtra, India

Abstract

The long-standing problem of low aqueous solubility, which affects about 90% of all new drug molecules under development, requires an immediate need for alternative approaches apart from the usual practice of crystallization. Polymer-composite-assisted crystal engineering is a novel technique for overcoming the aforementioned problem. This involves the addition of accepted pharmaceutical polymers, such as HPMC, PVP, PEG, and Eudragit copolymers in a single process, which can promote nucleation, stabilize the metastable crystals, and maintain drug supersaturation in the gastrointestinal tract. A pharmaceutical co-crystal is a multicomponent system where one of the components is an active pharmaceutical ingredient (API) while other components are pharmaceutically acceptable co-formers held by weak intermolecular interactions, including hydrogen bonding, van der Waals forces, and π-π stacking. The co-crystallization strategy proves to be a promising way for enhancing solubility, dissolution, bioavailability, stability, hygroscopicity, and tableting properties of API regardless of the ionization range. With the addition of a polymer into this binary API co-former system, a ternary architecture is created, which demonstrates performance that outperforms both that of the polymer-free co-crystal as well as an amorphous solid dispersion. An increase in solubility by factors of 2-8 over the parent API has been reported in the case of polymer-composite co-crystals, compared to that of the polymer-free co-crystal with an increase by factors of 1.5-5. This review provides a comprehensive overview of the preparation approaches, changes to physicochemical properties, and biomedical applications of the newly emerging class of polymers incorporated within co-crystals and solid solutions. Various solid-state approaches include polymer-assisted liquid-assisted grinding, hot-melt extrusion, and melt crystallization, while liquid state approaches include polymer-directed slurry conversion, reaction co-crystallisation, spray drying, and antisolvent co-precipitation. Changes to the physicochemical properties including physical and chemical stability, hygroscopicity, solubility, dissolution rate, and optical behavior due to incorporation of polymers are reviewed.

Keywords: Polymer composites; pharmaceutical co-crystals; crystal engineering; physicochemical properties; solid solutions; solid dosage forms; HPMC; PVP; PEG; Eudragit; co-crystallisation; bioavailability; BCS Class II/IV drugs

How to cite this article:
Sandeep P Shewale, Dipti Y Sakhare. Polymer Composite-Assisted Crystal Engineering for Drug Synthesis and Property Control through Solid Solutions and Co-Crystals. Journal of Polymer & Composites. 2026; 14(03):-.
How to cite this URL:
Sandeep P Shewale, Dipti Y Sakhare. Polymer Composite-Assisted Crystal Engineering for Drug Synthesis and Property Control through Solid Solutions and Co-Crystals. Journal of Polymer & Composites. 2026; 14(03):-. Available from: https://journals.stmjournals.com/jopc/article=2026/view=243532


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Ahead of Print Subscription Review Article
Volume 14
03
Received 24/04/2026
Accepted 08/05/2026
Published 12/05/2026
Publication Time 18 Days
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