Advantages Over Other PCA Techniques

CritiTech’s approach to PCA uses a supercritical CO2-powered ultrasonic nozzle. Other companies in the industry that use PCA report techniques that use conventional capillary spray nozzles.

The main advantages of CritiTech’s approach over conventional PCA techniques are:

• The ultrasonic nozzle-based process is capable of producing discrete nanoparticles in an exceptionally narrow size range.
• CritiTech’s proprietary particle harvesting device allows continuous processing of compounds. Conventional SCF techniques require processing in batch lots.

Advantages Over Milling Techniques

CritiTech’s PCA method is superior to milling techniques because:

• Particle formation occurs in a far shorter time - minutes/hours as opposed to days/weeks.
• PCA produces a much narrower range of particle sizes than milling.
• Milling processes induce electrostatic charge on the particles, which necessitates coating of the resulting particles to prevent re-agglomeration. PCA methods do not induce such electrostatic charges onto particles.
• PCA processing does not require removal of the milling agent.
• PCA processing is safely conducted in closed systems with complete recovery of solvents and CO2 for reuse or safe disposal.

Advantages Over Fluidized Air Coating Techniques

CritiTech’s particle coating technology has significant advantages over the current system of spray coating that is standard in the industry. The use of supercritical carbon dioxide allows the process to work with coating materials that are only soluble in organic solvents, or are sensitive to elevated temperatures. Both of these factors preclude the use of Wurster-type fluidized bed coaters. Pharmaceutical compounds requiring taste masking, time-release, or an increased oral absorption by coating with drug nanoparticles are example markets for this process.

The CritiTech coating process has the following advantages over conventional fluidized air based coating processes:

• A significantly reduced risk of fire and explosion when using organic solvents due to operation at lower temperatures (31-45°C) with dense carbon dioxide.
• Enormous flexibility for controlling the size and morphology of particulate coatings. Several of the operating parameters (pressure, temperature, solute concentration, type of nozzle, type of solvent) are adjustable to achieve the desired coating.
• Easy separation and recycling of the organic solvent and the CO2
• Coatings that are virtually solvent-free can be obtained in a relatively short time. For additional information regarding these technologies, please contact the company.

Environmental Advantages

A final advantage of CritiTech’s SCF based technologies lies in the environmentally friendly nature of the processes. Organic solvents traditionally used in the industry may be hazardous to the environment or toxic to humans and animals. Because of the closed loop nature of the supercritical processes employed by CritiTech, the release of harmful substances to the atmosphere is substantially reduced, if not totally eliminated.