title: Cross-linked guar gum microspheres: a viable approach for improved delivery of anticancer drugs for the treatment of colorectal cancer.
abstract: In the present work, guar gum microspheres containing methotrexate (MTX) were prepared and characterized for local release of drug in the colon, which is a prerequisite for the effective treatment of colorectal cancer. Guar gum microspheres were prepared by the emulsification method using glutaraldehyde as a cross-linking agent. Surface morphological characteristics were investigated using scanning electron microscopy. Particle size, shape, and surface morphology were significantly affected by guar gum concentration, glutaraldehyde concentration, emulsifier concentration (Span 80), stirring rate, stirring time, and operating temperature. MTX-loaded microspheres demonstrated high entrapment efficiency (75.7%). The in vitro drug release was investigated using a US Pharmacopeia paddle type (type II) dissolution rate test apparatus in different media (phosphate-buffered saline [PBS], gastrointestinal fluid of different pH, and rat cecal content release medium), which was found to be affected by a change to the guar gum concentration and glutaraldehyde concentration. The drug release in PBS (pH 7.4) and simulated gastric fluids followed a similar pattern and had a similar release rate, while a significant increase in percent cumulative drug release (91.0%) was observed in the medium containing rat cecal content. In in vivo studies, guar gum microspheres delivered most of their drug load (79.0%) to the colon, whereas plain drug suspensions could deliver only 23% of their total dose to the target site. Guar gum microspheres showed adequate potential in achieving local release of drug in in vitro release studies, and this finding was further endorsed with in vivo studies.
authors.affiliation: Pharmaceutics Research Projects Laboratory, Department of Pharmaceutical Sciences, Sagar, MP India.
authors.forename: Mohini
authors.initials: M
authors.lastname: Chaurasia
authors.forename: Manish K
authors.initials: MK
authors.lastname: Chourasia
authors.forename: Nitin K
authors.initials: NK
authors.lastname: Jain
authors.forename: Aviral
authors.initials: A
authors.lastname: Jain
authors.forename: Vandana
authors.initials: V
authors.lastname: Soni
authors.forename: Yashwant
authors.initials: Y
authors.lastname: Gupta
authors.forename: Sanjay K
authors.initials: SK
authors.lastname: Jain
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D015179:Colorectal Neoplasms / Q000188:drug therapy / Q000378:metabolism*; D003432:Cross-Linking Reagents; D004337:Drug Carriers; D016503:Drug Delivery Systems; D005685:Galactans / Q000737:chemistry; D008351:Mannans / Q000737:chemistry; D008863:Microspheres; D010316:Particle Size; D053149:Plant Gums
chemical_list: D000970:Antineoplastic Agents; D003432:Cross-Linking Reagents; D004337:Drug Carriers; D005685:Galactans; D008351:Mannans; D053149:Plant Gums; C007894:guar gum