In vitro and sensory tests to design easy-to-swallow multi-particulate formulations

Abstract

Flexible dosing and ease of swallowing are key factors when designing oral drug delivery systems for paediatric and geriatric populations. Multi-particulate oral dosage forms can offer significant benefits over conventional capsules and tablets. This study proposes the use of an in vitro model to quantitatively investigate the swallowing dynamics in presence of multi-particulates. In vitro results were compared against sensory tests that considered the attributes of ease of swallowing and post-swallow residues. Water and hydrocolloids were considered as suspending vehicles, while the suspended phase consisted of cellulose pellets of two different average sizes. Both in vivo and in vitro tests reported easier swallow for smaller multi-particulates. Besides, water thin liquids appeared not optimal for complete oral clearance of the solids. The sensory study did not highlight significant differences between the levels of thickness of the hydrocolloids. Conversely, more discriminant results were obtained from in vitro tests, suggesting that a minimum critical viscosity is necessary to enable a smooth swallow, but increasing too much the carrier concentration affects swallowing negatively. These results highlight the important interplay of particle size and suspending vehicle rheology and the meaningful contribution that in vitro methods can provide to pre-screening multi-particulate oral drug delivery systems before sensory evaluation.

The role of extensional rheology in the oral phase of swallowing: an in vitro study

“…The injected bolus mass, the mass of bolus ejected after every in vitro swallow, and the mass of post-swallow oral residues left inside the plastic membrane were also recorded for each experiment. This parameter was found to correlate well with sensory data considering the in mouth grittiness and swallow after-feel of placebo formulations 5 .…”

The Swallowing Characteristics of Thickeners, Jellies and Yoghurt Observed Using an In Vitro Model

“…Clinical evaluation of swallowing using FEES or VFFS is cumbersome and invasive. The quantitative evaluations of the in vitro swallowing tests provides a non-invasive way to screen foodstuffs for suitability whilst reducing the number of clinical investigations and improving our understanding of how we can prepare safer foods for patients with dysphagia [41].…”

Easy to Swallow “Instant” Jelly Formulations for Sustained Release Gliclazide Delivery

“…Increasing the coating level decreased drug release rate from the microparticles and at CL25 the particles showed a f 2 value of 54.2 (p ¼ 0.6653) in comparison to Diamicron, demonstrating equivalent drug release according to the Food and Drug Administration (FDA) guideline. 28 Drug release was complete at the end of the dissolution test from Diamicron and microparticles with coating levels of CL16, CL20 and CL25, but not from microparticles with CL60. Figure 7 shows the effect of incorporation of the microparticles into the "instant" jellies on drug release from the coated microparticles.…”