An important feature of any dispense system that handles regulated recipes is the use of aseptic materials. The Zaxis eVmP Smart pump heads are made of chemically inert materials such as aluminum oxide, 316SS, or CKC (Ceramic/Kynar®/Ceramic).
The rotating and reciprocating single piston design of the eVmP does not require any valves which limits the number of moving parts exposed to the fluid being dispensed. This allows the pump to be run for millions of maintenance free cycles and facilitates easy disassembly for cleaning. To remove an eVmP pump head, simply remove the two bolts (four on a VS6-Series) holding the head to its drive.
Other positive displacement pumping technologies that do not both rotate and reciprocate, require valves on the inlet and outlet of the ports. These ports can become clogged and affect performance. For this reason, the valveless design of the eVmP smart pump is a major advantage over traditional pumping technologies.
For a clean in place or CIP protocol, simply maximize the shot volume or displacement by pressing a single button. The eVmP Smart Pump System is controlled by a TSi (Touchscreen Interface) that can communicate up to 32 pumps at one time. Between batch runs, using the TSi, select all pumps and press the dedicated Max Shot button. The preferred cleaner or solvent is then passed through the pump heads cleaning the entire fluid path with zero disassembly required. Traditional pharmaceutical dispensing technology requires manual adjustment to change the shot volume. This is both imprecise and time consuming. The ability to dynamically adjust the dispense volume electronically is a huge advantage for pharmaceutical manufacturing and should not be overlooked.
When dispensing chemistry that precipitates or crystallizes, with exposure to atmosphere, it is best to a choose pump head with an integrated washport. The washport acts as an isolation gland between the dispense fluid and atmosphere. This gland introduces an inert fluid to the piston between the fill chamber and the head seals that acts as a piston lubricant and atmospheric barrier. This barrier prevents any crystallization of chemistry that can be caused by evaporation.
Precision and Accuracy
The FDA has general drug manufacturing guidelines put in place “to assure batch uniformity and integrity of drug products.” 1
These guidelines cover things such as:
- Tablet or capsule weight variation
- Adequacy of mixing to assure uniformity and homogeneity
- Dissolution time and rate
- Clarity, completeness, or pH of solutions
To achieve the product consistency required by FDA guidelines, a Softgel dispense system must achieve high accuracy with a low relative standard deviation. Positive displacement pumps are preferred for pharmaceutical metered dispensing due to their high accuracy. Positive displacement pumps do not depend on back pressure for flow, they control flow rates by changing the speed at which the pump is driven.2
Most positive displacement pumps can be classified as rotating, such as a gear or screw pump, or reciprocating, such as a diaphragm or plunger pump. The eVmP uses a unique drive and piston design that both rotates and reciprocates to accomplish both valving and pumping, eliminating valves used in traditional piston pumps. eVmP Smart pumps have 1% or better full-scale accuracy as well as a 0.5 coefficient of variation resulting in accurate and repeatable metered dispensing without the use of valves.
Another feature created by Zaxis for the eVmP smart pump system is micro stepping. Positive displacement pumps are designed to be viscosity independent but in real world applications the viscosity of a fluid can minutely affect the desired dispense volume. Example: you have set your pump to dispense 50 microliters but during production the volume metered is consistently 49.8 microliters. The micro stepping feature makes slight adjustments to the volume metered allowing you to hit your desired target.
Achieving High Throughput
Manufacturing pharmaceuticals demands excessively high throughput and constant changeover. eVmP stands for Electronic Variable Metering Pump and the purpose of the systems patented design is the ability to change dose volume without the need to manually adjust the pump. Along with the stepper or a powerful 1500 RPM servo motor that drives the pump head piston, each eVmP contains a second stepper motor that controls the pump drives angle of articulation. This angle affects the travel distance of the pump heads piston thereby changing the dispense volume. This enables the electronic micro-stepping feature referred to above, the clean in place Max Shot feature and most importantly, the ability to easily and quickly change dispense volumes between batches/recipes.
Every eVmP Smart pump contains an onboard processor that can store up to 50 programs. These programs can be batch specific with different volumes, speeds, timing, etc…. A common saved program often set is a clean in place program. For example, at the beginning of a shift an operator can select the programs for every batch that will be run that day, with a clean in place program set to run between each batch. The pumps will automatically change over at the completion of every batch leaving the operator nothing to do but switch out the chemistry.
eVmP Smart Pump System Makes Pharmaceutical Dispensing Easy
The eVmP Smart Pump System is ideally suited for softgel dispensing. The aseptic materials that are easy to dismantle for an autoclave, or simply clean in place, combined with integrated washports and an auto-agitation feature make eVmPs optimal for handling pharmaceutical chemistry. The eVmP onboard processors are compatible with Digital I/O, RS485 and EtherNet/IP for easy integration into any manufacturing system. The micro stepping feature helps dial in your target for the perfect shot size. The programmable volume creates a highly accurate and highly versatile tool for any dispensing system. The high accuracy and excellent standard deviation attained by the rotating and reciprocating, positive displacement design will expand your pharmaceutical manufacturing core competencies.
- Food and Drug Administration. Code of Federal Regulations Title 21, https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=211.110. Revised 1 Apr. 2019.
- Science Direct. Positive Displacement Pumps, https://www.sciencedirect.com/topics/engineering/positive-displacement-pumps. Accessed 14 May 2020.