What are some of the commonly described challenges we face today in drug dissolution testing?
Dissolution testing is a labor intensive test from setup and initiation, sampling through analysis, and reporting. Each step in the process has its unique challenges; manual sampling requires a significant amount of human involvement while semi- and fully automated sampling involve mechanical systems that move samples outside of the dissolution vessel. With mechanical systems there are pumps, valves, and tubing that can fail or become clogged due to particulates, resulting in missed samples and possibly a failed test. Immediate release testing presents its own set of sampling challenges where only a few samples can be taken due to limitations in speed of sampling systems or by the speed at which the scientist can manually pull the samples. The labor involved with all forms of sample handling including all the setup time, sampling, filtration, transfer, and possible dilutions all contribute to the increasing cost of performing dissolution testing. Performing non-technical tasks with skilled labor is extremely costly as well and increased testing demands combined with reduced personnel require laboratories do more with very limited resources. In addition, the lag time between sample collection and making an informed decision about formulation development or release testing can be days to weeks. This is typically caused by unnecessary reliance on HPLC for analysis with run times of a few minutes to an hour.
UV Analysis has remained one of the most common dissolution techniques. What are some of the key benefits to this method?
The ease of use and speed of analysis (<1 second per measurement), minimal consumables, and no hazardous waste byproduct from the test other than that which is generated from the dissolution test itself are all key benefits for UV analysis.
Explain the benefits of using In-situ Fiber Optic UV Dissolution methods when dealing with extended release and immediate release tablets.
The use of fiber optics for dissolution testing provides several key benefits; the in-situ measurement eliminates the need for sample handling which can introduce error and variability in results. The labor and associated consumables needed for sampling are no longer necessary and the near real-time display of dissolution results provides immediate feedback to the scientists, saving precious time during formulation development or release testing.
How have fiber optic dissolution methods lowered labor intensity, accelerated formulation development, and reduced data turnaround time?
The use of fiber optics has eliminated the labor associated with sample collection, data analysis, and the generation of dissolution results. Fiber optic probes are inserted into the dissolution vessels and the test begins. There is no further user involvement required until the test ends—at which point the probes have to be removed and the dissolution vessels prepared for the next test. All the labor traditionally required while the test is underway has been completely eliminated. This is a critical reduction in labor considering the need for running additional shifts or paying for overtime for extended release product testing. Fiber optics also accelerate formulation development as results can be generated and displayed as quickly as every 5 seconds giving the formulation scientist immediate feedback about the release rate. Tests can be terminated before completion if the information generated indicates the stated objective is not going to be met as opposed to waiting for the test to complete and the samples processed off-line via UV or LC. This could take up to a week depending on capacity and instrument availability. It should also be noted that fiber optics provides value for all formulations, even those that will ultimately require separation by LC, because of its ability to plot near real-time results.
Explain the advancements achieved by taking analysis directly to the vessel where dissolution occurs.
By taking the analysis directly into the vessels, the precision and accuracy of the results being generated have been improved and decision times are drastically accelerated; testing results that normally take weeks to generate can now be done in a day or two. In a time when scientists are asked to do more in less time and when speed is a competitive advantage, fiber optic UV is a necessary tool in every dissolution lab and company looking for a competitive advantage.