Abstract

Background: Poor solubility and low oral bioavailability are major challenges associated with the oral delivery of the antidiabetic drug Vigna radiata (VR). Nanostructured lipid carriers (NLCs) have emerged as a promising strategy to overcome these limitations and improve the therapeutic efficacy of VR. This study investigated the potential of NLCs for VR delivery and explored the influence of formulation parameters on NLC properties and drug release behavior.

Methods: NLCs loaded with VR were prepared using the melt emulsion ultrafiltration technique. The effect of two key formulation variables – the ratio of liquid lipid to solid lipid and the concentration of the surfactant were investigated in terms of particle size, zeta potential, and drug encapsulation efficiency. The in-vitro release profiles of the VR-NLC formulations were evaluated, and the optimal formulation was subjected to further analysis to investigate its release kinetics.

Results: The NLCs exhibited particle sizes ranging from 108.9 to 192.3 nm and all formulations possessed a negative zeta potential (-3.68 to -10.9 mV), indicating good stability and potential for resisting aggregation. Interestingly, the lowest solid lipid to liquid lipid ratio and the lowest surfactant concentration yielded the highest drug encapsulation efficiency, highlighting the complex interplay between these factors. All VR-NLC formulations exhibited a biphasic, time-dependent in-vitro release pattern, suggesting an initial burst release followed by a sustained release phase. This biphasic profile is promising for achieving both rapid onset of action and long-lasting glycemic control, which are crucial aspects of effective diabetes management.

The optimized NLC formulation showed an in-vitro release pattern that adhered to the Higuchi diffusion model, suggesting a controlled release mechanism where the drug diffuses steadily out of the NLC matrix. This finding indicates potentially predictable and consistent drug delivery in-vivo.

Conclusion: This study demonstrates the potential of NLCs as a promising platform for the controlled oral delivery of VR. NLCs can overcome the inherent limitations of VR and provide a convenient and effective oral antidiabetic option for patients. Further research is needed to confirm the efficacy and safety of NLC-encapsulated VR in-vivo using relevant animal models. This will pave the way for the development of a novel and potentially transformative treatment option for diabetes.

Keywords: NLC, Vigna radiata extract, in-vitro, in-vivo, anti-diabetic, ultrafiltration technique, one work fourier transform infrared, encapsulation efficiency (EE).

Graphical Abstract