
Microneedles to Monitor Drugs Instead of Administer Them
7/28/16 Using a microneedle, which punctures the outer layer of skin, researchers at the University of British Columbia have created a way to monitor drug levels in patients that is easier and less invasive. Currently, in order to monitor levels of powerful antibiotics, a doctor has to draw blood multiple times per day from a patient. The researchers have created a microneedle system to check the levels of the drug easily without piercing the skin. This microneedle patch measures the drug in a persons system based on concentrations in fluid just below the top layer of skin, making monitoring the drug easier and far less painful for patients and doctors.
So far most microneedle devices have been created to deliver drugs to patients, but this new one suggests it can monitor the drug levels in a human body. For example Vancomycin is a powerful antibiotic used to treat difficult infections and is administered intravenously. Then a doctor has to draw blood from the patient three to four times per day to monitor its levels in the body because it has the potential for life-threatening toxic side effects.
“This is probably one of the smallest probe volumes ever recorded for a medically relevant analysis,” Dr. Urs Hafeli, an associate professor of pharmaceutical sciences at the University of British Columbia, said in a press release. “The combination of knowhow from UBC and PSI, bringing together microneedles, microfluidics, optics and biotechnology, allowed us to create such a device capable of both collecting the fluid and performing the analysis in one device.”
The researchers created and tested this optofluidic device with a small circle of microneedles to be pressed on the skin for sample collection. The array of microneedles (< 500 microns long) is pressed against a patient’s skin, drawing a small amount of fluid from beneath the outer layer of skin without puncturing any of the layers below it. The fluid is drawn up into the device, which causes a chemical reaction that can be detected using an optical sensor, revealing the concentration of vancomycin in a patient’s system.
“Many groups are researching microneedle technology for painless vaccines and drug delivery,” said Sahan Ranamukhaarachchi, a doctoral student of applied science and pharmaceutical sciences at the University of British Columbia. “Using them to painlessly monitor drugs is a newer idea.”
Micro needles are a concept that we have been involved with, please see our micro needle array projects on our micro molding page: https://www.microengineeringsolutions.com/mes_service/micro-molding/
Micro Medical Device Moves With Mechanical Energy
Mesoscale Nanoparticle Targeted Drug Delivery
7/14/16 In previous blogs we have written about new targeted drug delivery development and how its possible using micro medical device components. There was a recent article by the Memorial Sloan Kettering Cancer Center (MSKCC) that we found interesting and the topic keeps in line with the blogging we have been doing.
The topic of the article was on renal cell carcinoma a common form of kidney cancer. Scientists at MSKCC have engineered a micro-sized particle that could make it possible to deliver drugs directly to the affected kidneys and minimize their uptake in other organs. The device, called a mesoscale nanoparticle, could help boost the usefulness of some kidney cancer drugs and might also be used in the treatment and diagnosis of other kidney conditions.
Nanoparticles are polymers between 1-100 nanometers and can be loaded with drugs or imaging agents (an average human cell measures about 50,000 nanometers). They hold promise for many medical applications, partly because they are biocompatible with living tissue and have unusual chemical and physical properties.
The kidney-bound particle is the result of an incidental finding made while studying how the size and chemical properties of some nanomaterials could be modulated to guide their distribution in the body. The goal of the project was to create a nanoparticle capable of targeting cancer drugs to the lung. They produced a number of nanoparticles of different sizes and chemical properties which were then injected into mice and their location tracked using CT scans and other imaging methods.
The results of the initial experiments were mixed. In particular, one of the particles didn’t behave as expected. The researchers could find only low levels of it in the animals’ lungs, and very little in the liver or spleen, where many similar substances tend to gather. It surprisingly ended up in the proximal tubule of the kidney where mesoscale nanoparticles are absorbed. Interestingly enough, the proximal tubule is where renal cell carcinoma (RCC) originates.
The MSKCC team is now working to develop a nanoparticle-based technology to deliver chemotherapy or targeted therapies directly to the site of RCC. They hope the method will help reduce side effects of the drugs by keeping them away from other organs. They are focusing on trials that have failed and were abandoned in hopes of revamping their research.
The researchers are also exploring the use of this to help repair kidney failure, a common problem in people who receive chemotherapy for various types of cancer because the proximal tubule is often the first site of damage.
Micro Implantable Drug Delivery Device Advantages
7/7/16 Fueling the market for implantable drug delivery devices are the rising occurrence of cardiovascular diseases and the increasing number of interventional cardiologists. Implantable drug delivery devices provide many advantages over the traditional oral drug delivery method. They offer localized and site-specific delivery, which is extremely important in applications such as cardiology and oncology because it enhances the treatment’s effectiveness and lowers its damage/side effects to healthy tissues.
Transparency Market Research (TMR), a market intelligence company, acknowledges the top two advantages of using implantable drug delivery devices. These advantages are:
1. Convenience: Implantable drug delivery devices allow patients to take medication outside of a hospital setting and involve relatively marginal medical observation. In addition, implantation treatments involve a reduced risk of infections and complications as compared to indwelling catheter-based infusion systems.
2. Automation of Drug Delivery: Drug delivery via an implant eliminates patient errors, which in turn increases the treatment regimen immensely.
Non-biodegradable drug delivery devices are extremely popular when working with hormone regulation, contraception, oncology, abuse deterrence, and pain management.
1. Hormone regulation: Women’s transmucosal hormone contraceptives can deliver a for a set time period (a few months-3 years) to treat symptoms related to menopause. Another example is Merck & Co.’s Nexplanon®. This device is made using EVA and delivers 68 mg of etonogestrel for a period of three years. These devices usually consist of an implant in a subcutaneous manner in the arm of the patient.
2. Diabetes treatment: Non-biodegradable implantable drug delivery devices present a unique solutions for diabetics. They are a long term implant delivery technology for the treatment of type II diabetes.
Micro Engineering currently works on projects in this field. If you have a project that falls into this category, please browse our website and call us to discuss your options.