There's a revolution in medical care that will make an inexorable impact on our lives. Whether one is being treated in a doctor's office, a medical laboratory, a hospital, or an emergency room, the coalescing medical advances are nothing short of amazing, including in-vivo (inside the body) and in-vitro (outside the body) diagnostic and therapeutic devices, and implantable and disease-targeting drugs.
These breakthroughs are largely based on emerging microtechnology and nanotechnology electronics. New tools with microrobotic grippers and tweezers will offer surgeons an unparalleled ability to operate on just about any part of the human body, no matter how small. Targeted drug delivery and analysis devices also are making great gains.
Micro-array lab-on-a-chip products for point-of-care diagnostics are already at the clinical trial stage. They will be available once the U.S. Food and Drug Administration (FDA) approves them. A micro-array lab-on-a-chip is an array matrix that lets doctors instantaneously analyze fluids, cells, and even DNA structure right in the office. This high-throughput analysis will be a boon to medical and pharmaceutical industries. The lab-on-a-chip promises high-speed fine-tuned identification of the protein sequences that make a difference in specific diseases. Many of these devices can be worn on the wrist or tucked under a belt.
Expect to see diagnostic chips for such vital organs as the brain, heart, eyes, lungs, liver, and kidneys, possibly within five years. We can look forward to new therapeutic methods to treat various medical conditions. Just one example is a novel means to stimulate retinal cells affected by macular degeneration and retinitis pigmentosa, two common eye diseases.
Implantable brain probes for the detailed study of neural activity are already here. Under rapid development too are so-called "brain-on-a-chip" devices, which allow physicians to view the simultaneous interactions occurring between brain neurons. The devices enable treatment of various mental and other brain disorders.
Revolution Coming In Drug Analysis And Delivery: Few things in the medical sciences are more exciting than the drug analysis and delivery systems expected over the next few years. Implantable devices consisting of sealed arrays of reservoirs will be available for in-vivo and in-vitro drug analysis and delivery. These devices are filled with chemicals that can be released on demand and can check the efficacy of drugs released over long periods of time (Fig. 1). Subcutaneous implanted mi-crochips have already proven their value in these applications.
It may take a few more years, but nano-size porous membranes with 7- to 9-nm pores will offer size-based exclusion and controlled diffusion of drug biomolecules. The idea is to allow the diffusion into the body of small therapeutic drug molecules while excluding larger molecules, providing significant advantages in cell immuno-isolation and controlled drug-delivery applications.
Depending on the medical application, these devices can be administered by many different routes: by subcutaneous implants, surgical implants, oral pills, intravenous injection, and possibly pulmonary inhalation. These biomolecular drugs have the potential to significantly improve drug delivery for the treatment of chronic hepatitis C, anemia, neutropenia, multiple sclerosis, psychosis, diabetes, and cancer. One of the more exciting developments is an intravenous injectable drug-delivery platform to target and treat metastatic solid-breast tumors as well as lung and colon cancer tumors.
Already, patch-type insulin pumps can diffuse insulin into the body. The patch is worn on a patient's arm and has a metering device to show how much insulin has been delivered over a period of time. Implantable pumps and MEMS micro-needles for the precise and effective delivery of insulin are on the horizon (Fig. 2). Before long, micro-insulin pumps, complete with the insulin, a pump, a microprocessor, and microneedle arrays for drug injection, no bigger than 1 or 2 cm2, will be available for implants.