FEEDBACK-REGULATED DRUG DELIVERY SYSTEMS (2).pptx

FEEDBACK-REGULATED DRUG DELIVERY SYSTEMS

1. FEEDBACK-REGULATED DRUG DELIVERY SYSTEMS (FRDDS) PRESENTED BY : Elahe Tolideh 1st M. PHARM Dept of Pharmaceutics Al Ameen college of pharmacy Bangalore SUBMITTED TO : Dr. Preeti Karwa HOD Dept of Pharmaceutics Al Ameen college of pharmacy Bangalore ‹#›

2. Controlled Release Drug Delivery Systems Release therapeutic agents at predetermined rates, durations, and target sites to achieve optimal therapeutic outcomes. (1) Rate programmed drug delivery system (2) Activated modulated drug delivery system (3) Feedback regulated drug delivery system (4) Site targeting drug delivery system ‹#›

3. Feedback Regulated Drug Delivery System Release of drug molecules from the delivery systems is activated by a triggering agent , such as a biochemical substance, in the body in real time and also regulated by its concentration via some feedback mechanisms. The rate of drug release is then controlled by the concentration of triggering agent detected by a sensor in the feedback-regulated mechanism. ‹#›

4. Basic Structure ‹#›

5. Classification A. Bioerosion-Regulated Drug Delivery System B. Bioresponsive Drug Delivery Systems C. Self-Regulating Drug Delivery Systems ‹#›

6. Bioerosion-Regulated Drug Delivery System Drug-dispersed bioerodible matrix made from PVME-HE. Protective Coating: The matrix was coated with a layer of immobilized urease. Example: Hydrocortisone In neutral pH, the polymer erodes very slowly. In the presence of urea, the urease enzyme breaks down urea into ammonia. The ammonia raises the pH, causing the polymer matrix to degrade rapidly. This results in the release of drug molecules. ‹#›

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8. Bioresponsive Drug Delivery Systems Developed by Horbett. The drug reservoir is enclosed in a bioresponsive polymeric membrane The permeability of the membrane is controlled by the concentration of a biochemical agent in the surrounding tissue. Example: Glucose-Triggered Insulin Delivery System ‹#›

9. Smart Hydrogel Wrapp: Insulin is stored inside a hydrogel membrane that controls its release. Glucose Sensor: The membrane contains glucose oxidase , which detects glucose levels. Triggered Release: When glucose enters, it converts into gluconic acid , causing the membrane to swell and open , releasing insulin. Self-Regulating: The system automatically adjusts insulin release based on glucose levels, mimicking the body's natural response. ‹#›

10. Glucose-Responsive Insulin Delivery Systems Using Nanocarriers ‹#›

11. Self-Regulating Drug Delivery Systems Works based on a reversible and competitive binding process to control drug release. The drug is stored inside a semipermeable polymeric membrane as a drug complex. A biochemical agent (e.g., glucose) from the body triggers drug release by diffusing into the membrane. Example: I nsulin delivery system using a lectin-based ‹#›

12. Insulin delivery system using a lectin-based reversible binding mechanism. Insulin is bound to sugar molecules (e.g., maltose) to form an insulin-sugar-lectin complex. The complex is encapsulated in a semipermeable membrane. When glucose enters, it competes for binding sites on lectin, causing insulin to be released. ‹#›

13. FRDDS In Maintaining Blood Glucose Levels In Pancreatectomized Dogs ‹#›

14. Disadvantage: Non-linear insulin release: The system does not proportionally adjust insulin release to glucose levels. Example: A glucose level of 500 mg/dl triggers insulin release at only twice the rate of that at 50 mg/dl, instead of a significantly higher rate. Complex formulation: The development process relies on glycosylated insulin-Concanavalin A complex, which is encapsulated inside a polymer membrane, making the system more intricate. ‹#›

15. Morphine O verdose Mechanism of Action Morphine overdose causes respiratory depression , increasing CO₂ levels in the blood. The CO₂ reacts with water , forming bicarbonate (HCO₃⁻) and H⁺ ions , lowering pH. This triggers the drug carrier to release naloxone , reversing morphine’s effects. ‹#›

16. Polyurethane P olymeric material composed of organic units drug delivery systems, due to its biocompatibility, flexibility, and durability. Roles in FRDDS: pH-Responsive Release – PU hydrogels alter swelling behavior based on pH, useful for targeted drug delivery in the GI tract and tumor therapy. Enzyme-Triggered Release – PU degrades in the presence of specific enzymes, allowing localized and self-regulated drug release in diseased tissues. Temperature-Sensitive PU – Releases drugs at specific body temperatures, beneficial for fever-triggered therapies. PU Nanoparticles – Enables controlled and sustained drug release, modifiable for external stimuli like magnetic fields or ultrasound. ‹#›

17. Recent advances in glucose-responsive insulin delivery systems: novel hydrogels and future applications Glucose-Responsive Insulin Delivery Systems (GRIDS): These systems aim to mimic the body's natural insulin regulation by releasing insulin in response to elevated blood glucose levels, thereby reducing the need for frequent blood sugar monitoring and manual insulin injections. ‹#›

18. References https://pmc.ncbi.nlm.nih.gov/articles/PMC9438743/ https://www.mdpi.com/2218-273X/12/9/1198 Novel Drug Delivery Systems, Yie W Chien ‹#›