Satyam Ambardekar* 1
Novel drug delivery systems is the new system Recent advances in the understanding of pharmacokinetic & pharmacodynamic behaviour of drug have offer a more rational approach to the development of optimal drug delivery system. the novel drug delivery systems (NDDS) are carriers which maintain the drug concentration in therapeutic range for longer period of time There are several advantages of novel drug delivery systems over conventional drug delivery.
1. Optimum therapeutic- drug concentration in the blood or in tissue may be maintained over a prolonged period of time.
2. Pre- determined release rates of extended period of time may be achieved.
3. Duration for short half- life drug may be increased.
4. By targeting the site of action, side effects may be eliminated.
5. Frequent dosing and wastage of the drug may be reduced or excluded. 6. Better patient compliance may be ensured.
Novel drug delivery systems
• Sustained- or controlled- drug delivery systems provide drug action at a pre-determined rate by providing a prolonged or constant (Zero-order) release respectively, at the therapeutically effective levels in the circulation.
• Localized drug delivery devices provide drug action through spatial or temporal control of drug release (usually rate- limiting) in the vicinity of the target.
• Rate- pre-programmed drug delivery systems provide drug action by manipulating the release of drug molecules by system design which control the molecular diffusion of drug molecules.
• Targeted drug delivery provides drug action by using carries either for passive or active targeting or one base or self-programmed approach, usually anchored with suitable sensory devices, which recognize their receptor at the target.
Table 1.0 Classification of sustained or controlled release system based on their rate – controlled mechanism.
|
Type of System                                    |
Rate control Mechanism |
|
Diffusion – controlled |
 |
|
Reservoir systems (Ocusert) |
Diffusion through membrane |
|
Monolithic systems (Transdermal drug) |
Diffusion through membrane |
|
Delivery system- Nitro -dur) |
 |
|
Water penetration controlled |
 |
|
Osmotic systems (Oros, Alzet osmotic pump) |
Osmotic transport of water through semi-permeable membrane |
|
Swelling system (hydrogel) |
Water penetration into glassy polymer |
|
Chemically - controlled |
 |
|
Pendent systems |
Combination of hydrolysis of pendent group diffusion from bulk polymer |
|
Ion – exchange resins |
Exchange of acidic or basic drug with the ions present on resins |
10.5281/zenodo.15718612