NanoBiotechnologysp13-bty-001 1
NanoGate Implants
Introduction:
In 2005, the largest sectors of the market consisted of su...
NanoBiotechnologysp13-bty-001 2
Passive Delivery Systems
1. Membrane Controlled Diffusion System
Diffusion controlled syst...
NanoBiotechnologysp13-bty-001 3
Others type of passive drug delivery Nano gate implants are Microchannel implants and osmo...
NanoBiotechnologysp13-bty-001 4
Conclusion
The knowledge and tools enabling the development of reservoir-based drug delive...
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Nanogate Implants

In 2005, the largest sectors of the market consisted of sustained release implants and transdermal drug delivery systems. The global market for drug delivery systems was $134.3B in 2008 and projected to increase to $196.4B in 2014. This market potential has provided the driving force behind the development of nanodelivery systems. Smaller systems can incorporate features or mechanisms that allow more precise control over the drug delivery rate, enable the patient or physician to actively start/modify/stop drug release in an interactive format, and provide ways to reach difficult to treat locations. These next generation targeted delivery systems offer the possibility that the drug can be delivered preferentially to a relatively inaccessible site, a specific tissue type, or simply to limit side effects due to systemic exposure.
Published on: Mar 3, 2016
Published in: Technology      
Source: www.slideshare.net


Transcripts - Nanogate Implants

  • 1. NanoBiotechnologysp13-bty-001 1 NanoGate Implants Introduction: In 2005, the largest sectors of the market consisted of sustained release implants and transdermal drug delivery systems. The global market for drug delivery systems was $134.3B in 2008 and projected to increase to $196.4B in 2014. This market potential has provided the driving force behind the development of nanodelivery systems. Smaller systems can incorporate features or mechanisms that allow more precise control over the drug delivery rate, enable the patient or physician to actively start/modify/stop drug release in an interactive format, and provide ways to reach difficult to treat locations. These next generation targeted delivery systems offer the possibility that the drug can be delivered preferentially to a relatively inaccessible site, a specific tissue type, or simply to limit side effects due to systemic exposure. NanoGate implant A drug delivery device that includes a device for implantation into the body, the capsule further contains a reservoir for containing substances such as therapeutic agent, at least one port allowing the substance to diffuse from or otherwise exit the reservoir and Nano pore exit for controlling the rate of diffusion of substances from exit port. For example The application of microfabrication and MEMS (microelectromechanical systems) technologies have resulted in a new class of oral delivery systems. Silicon nanoparticles having dimensions of 50 μm × 50 μm × 2 μm, with 25 μm × 25 μm × 1 μm deep wells were designed for targeted oral drug delivery. Categories Implantable drug delivery systems can be placed into three categories • Passive – a system where drug release is pre-determined by the materials, fabrication methods, or drug formulation and cannot be controlled after implantation • Active – a system where drug release is controlled after implantation using mechanical, electrical, magnetic, laser or other means Passive systems utilize diffusion, osmotic potential, or concentration gradients as their driving forces, while active systems include mechanical pumping, electrolysis, and other actuation methods.
  • 2. NanoBiotechnologysp13-bty-001 2 Passive Delivery Systems 1. Membrane Controlled Diffusion System Diffusion controlled systems, in their simplest forms, rely on diffusion of drug out of or through a polymer layer that may be nonporous or microporous. The rate determining step may be diffusion through the membrane structure or transport of drug through the static aqueous diffusion layer. For membrane controlled diffusion, the diffusion coefficient is dictated by the size of the drug molecule and the pore size or space between the polymer chains. This technology has been widely used for delivery from reservoir-based oral and transdermal systems and has recently been adapted for implants. For example the Retisert® implant (approved in 2005) measures 3 mm × 2 mm × 5 mm and is the second generation Medidur™ technology. 2. Matrix Controlled Diffusion Systems A subclass of diffusion controlled systems takes advantage of a combination of drug release from a polymer matrix via porosity and polymer erosion. Oncology is a therapeutic area that has taken advantage of passive, diffusion controlled implantable systems. Resorbable multi-reservoir arrays made from poly (l-lactic acid) and/or PLGA were fabricated, where each reservoir was covered with a bioerodible membrane cap comprised of varying ratios and molecular weights of PLGA. The devices measured ~11.9 mm in diameter, were 480-560 μm thick, and contained thirty six 120-130 nl reservoirs FIG 1: Passive, matrix controlled drug delivery systems including a bioerodible PLGA implant
  • 3. NanoBiotechnologysp13-bty-001 3 Others type of passive drug delivery Nano gate implants are Microchannel implants and osmotic pumps Active Delivery Systems 1. Single Reservoir Active System Pumps generally include a drug reservoir, an actuator, and one or more valves in order to accurately control the delivery of small volumes of a drug in solution. They may operate by manual actuation, electrolysis, piezoelectric actuation, resistive heating, magnetic actuation, or by incorporation of reversible polymeric valves. The simplest example of an active drug delivery pump is one that is actuated manually by pressing on it with an instrument or a finger. Such a system was designed for the treatment of glaucoma, age-related macular degeneration, and diabetic retinopathy. The pump is fabricated from three layers of polymethylsiloxane (PDMS) using soft lithography. The device was sutured to the outside of the eye and contained a drug reservoir of approximately 200 μl, a check valve, and a cannula (10 mm × 1 mm × 1 mm) placed through the wall of the eye. When the pump was manually actuated by pressing on the drug reservoir, the increase in pressure in the reservoir caused the check valve in the cannula to open, dispensing the drug. Fig 2: Manually actuated drug delivery pump for ophthalmic use 2. Multi-Reservoir Active Systems The advantage of one active delivery mechanism versus another, and the need for more than one drug reservoir, is highly dependent on the treatment modality of the specific disease state and the preferred delivery profile. Active delivery from multi-reservoir array implants can be actuated by electrochemical, electro thermal, or laser means.
  • 4. NanoBiotechnologysp13-bty-001 4 Conclusion The knowledge and tools enabling the development of reservoir-based drug delivery systems utilizing nanotechnology have come from number of diverse fields of study including chemistry, materials science, mechanics, information technology, and microelectronics. The innovations at the core of such novel oral, dermal, and implantable delivery systems come from the intersection of these disparate fields. Devices combining reservoirs and nanotechnology driven by passive or active mechanisms are enabling the delivery of both small and macromolecule drugs with increased specificity and control. While tremendous progress continues on the development of micro and nanotechnology for reservoir-based drug delivery devices, much additional work will be required to translate the promising technology into safe and effective, well-controlled, patient acceptable products. References 1. http://www.valeritas.com/ 2. http://link.springer.com/article/10.1385%2FNBT%3A1%3A1%3A035 3. Book therapeutics micro/Nano technology by Mauro Ferrari 4. Reservoir-Based Drug Delivery Systems Utilizing Microtechnology Cynthia L. Stevensona, John T. Santini Jr.a,*, and Robert Langerb 5. http://www.debiotech.com/ 6. www.ondemandtx.com 7. Maloney JM, Uhland SA, Polito BF, Sheppard NF Jr, Pelta CM, Santini JT Jr. Electrothermally activated microchips for implantable drug delivery and biosensing. J Control Release. 2005; 109:244–255. [PubMed: 16278032] 8. Verma RK, Garg S. Drug delivery technologies and future directions. Pharmaceutical Technology. 2001; 25:1–14.

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