Silicone oil has long been used in the pharmaceutical industry as a lubricant for syringes. It serves to reduce the force necessary to depress the plunger, and can make procedures more comfortable and safer for the doctor and patient. In intraocular injections, it allows the needle to slide more easily through the eye wall. However, silicone oil droplets released by these needles often impact the efficacy of ophthalmic drug products more than other therapies, as they can cause patients to see floaters following administration.
A recent study produced by the University of Colorado Center for Pharmaceutical Biotechnology compared large numbers of syringes and needles used in intravitreal injections (IVIs). The team analyzed the particles released from each syringe and needle and discovered great variability in the results. The concentration, size distribution, and morphology of the micro-sized particles were characterized using FlowCam.
Flow imaging microscopy (FIM) with FlowCam is ideally suited to detecting silicone oil droplets. Since they are visually distinct from other common particle types like protein aggregates, images of silicone oil can easily be differentiated and identified visually in a dataset and through image analysis tools like classification or artificial intelligence-based solutions such as VisualAI software for FlowCam.
In the study, silicone oil dropets, fibers, and plastic particles were found in varying concentrations across all samples. Ophthalmologists who perform IVIs should be aware of the wide variability in particles from syringes and be wary of the potential clinical implications of silicone oil and other particles injected into the vitreous of their patients. The study determined that better control is needed in the siliconization process and in managing particle loads from these devices, even the silicone-free ones, in order to provide better patient safety.
Read the entire paper here: High Particle Variability Across Siliconized and Oil-Free Syringes and Needles from the Same Lots
Learn more about the importance of monitoring for silicone oil droplets in biotherapeutics
