en ترکیبات طبیعی Natural products مروری Review article <div style="text-align: justify;"><strong>Background</strong>: Controlled drug delivery systems (DDS) are designed to release therapeutic agents in a regulated manner to maintain consistent plasma drug concentrations. Among these systems, gastro-retentive DDS (GRDDS) have gained considerable attention due to their ability to prolong gastric residence time, thereby enhancing drug bioavailability and therapeutic efficacy for drugs absorbed primarily in the stomach or upper gastrointestinal tract.<br> <strong>Objectives</strong>: This review aimed to critically examine the role of pectin-based polymers in the development of GRDDS, with particular emphasis on formulation strategies using high- and low-methoxylated pectins.<br> <strong>Results</strong>: Pectin, a naturally derived polysaccharide, is widely utilized in pharmaceutical formulations owing to its biocompatibility, biodegradability, non-toxic nature, and excellent gel-forming capacity. Based on its degree of methoxylation (DM), pectin is classified into high-methoxylated and low-methoxylated forms, each exhibiting distinct physicochemical and functional properties. Low-methoxylated pectin has been extensively explored in floating DDS due to its calcium-dependent gelation behavior. In contrast, high-methoxylated pectin demonstrates strong mucoadhesive properties, making it suitable for mucoadhesive gastro-retentive formulations. Comparative studies with other natural polymers highlight the versatility of pectin in GRDDS design.<br> <strong>Conclusion</strong>: Pectin-based gastro-retentive formulations represent a promising and sustainable approach for controlled drug delivery. Understanding the distinct characteristics of high- and low-methoxylated pectin enables the rational design of effective GRDDS, potentially improving therapeutic outcomes and patient compliance.</div> Gastro-retentive drug delivery systems (GRDDS), Controlled drug delivery, Pectin-based polymers, High-methoxylated pectin, Low-methoxylated pectin, Floating DDS, Mucoadhesive formulations 9 26 http://pbr.mazums.ac.ir/browse.php?a_code=A-10-1286-2&slc_lang=en&sid=1 Aeman Anis mdanisakhter5@gmail.com 100319475328460012018 0009-0002-7468-8808 No School of Pharmacy, Techno India University, Kolkata, India. Arpan Das arpandas13733@gmail.com 100319475328460012019 100319475328460012019 No BCDA College of Pharmacy and Technology, Kolkata, India. Moumita Das Kirtania mmtdas@gmail.com 100319475328460012020 100319475328460012020 No BCDA College of Pharmacy and Technology, Kolkata, India. Laboni Das laboni.d@technoindiaeducation.com 100319475328460012021 0009-0008-9536-9543 No School of Pharmacy, Techno India University, Kolkata, India. Gopa Roy Biswas goparoy2020@gmail.com 100319475328460012022 100319475328460012022 Yes School of Pharmacy, Techno India University, Kolkata, India.