الفهرس 
Pharmaceutical approaches for colon targeting drug delivery
Liquid Crystalline Nanoparticles (LCNPs)Only 14 pages are availabe for public view
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Abstract
Colorectal cancer (CRC) is one of the leading tumors around the world. It is the third most commonly diagnosed cancer and the second most lethal disease worldwide. There are several conventional methods for colon cancer treatment that include surgery, radiation therapy, and chemotherapy. Unfortunately, chemotherapy not only attacks the malignant cells but also harms the normal tissues. Patient ultimately suffer from undesired side effect such as, hand-foot syndrome, neutropenia, anemia, diarrhea and nausea. Oral dosage form is the preferred route of administering drugs for colon-specific disorders. Despite the advantages of colon-specific oral drug delivery, severe hurdles must be addressed by drug delivery technology for effective treatment. The pH of the gastrointestinal tract (GIT) fluctuates dramatically, from severely acidic in the stomach (pH 1.3-3.5) to almost neutral in the small intestine and finally mildly acidic in the colon (pH 6-8). The acidic environment may inactivate drugs that are unstable over such a broad pH range. Furthermore, The GI tract contains pancreatic enzymes, bicarbonate and bile salts secreted from the bile duct, and enzymes generated by colonic bacteria.
Microbeads (MBs) are solid and free-flowing particulate carriers retaining dispersed particles of drugs in solution or crystalline form, allowing for prolonged or multiple release profiles of treatment with different active agents while minimizing side effects. They are almost spherical, small with diameters between 0.5 to 1000 μm. Furthermore, the beads can entrap drug to be delivered locally at higher concentrations, making sure that therapeutic levels are reached at the target area while minimizing adverse effects.