Sladek Svenja, McCartney Fiona, Eskander Mena, Dunne David J, Santos-Martinez Maria Jose, Benetti Federico, Tajber Lidia, Brayden David J
UCD School of Veterinary Medicine and UCD Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland.
School of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, Dublin 2, Ireland.
Pharmaceutics. 2020 Mar 12;12(3):259. doi: 10.3390/pharmaceutics12030259.
The use of nanocarriers is being researched to achieve oral peptide delivery. Insulin-associated anionic polyelectrolyte nanoparticle complexes (PECs) were formed that comprised hyaluronic acid and chitosan in an optimum mass mixing ratio of 5:1 (MR 5), followed by coating with a pH-dependent polymer. Free insulin was separated from PECs by size exclusion chromatography and then measured by HPLC. The association efficiency of insulin in PECs was >95% and the loading was ~83 µg/mg particles. Dynamic light scattering and nanoparticle tracking analysis of PECs revealed low polydispersity, a negative zeta potential range of -40 to -50 mV, and a diameter range of 95-200 nm. Dissolution studies in simulated small intestinal fluid (FaSSIF-V2) revealed that the PECs were colloidally stable. PECs that were coated with Eudragit L-100 delayed insulin release in FaSSIF-V2 and protected insulin against pancreatin attack more than uncoated PECs. Uncoated anionic PECs interacted weakly with mucin in vitro and were non-cytotoxic to Caco-2 cells. The coated and uncoated PECs, both concentrated further by ultrafiltration, permitted dosing of 50 IU/kg in rat jejunal instillations, but they failed to reduce plasma glucose or deliver insulin to the blood. When ad-mixed with the permeation enhancer (PE), sucrose laurate (100 mM), the physicochemical parameters of coated PECs were relatively unchanged, however blood glucose was reduced by 70%. In conclusion, the use of a PE allowed for the PEC-released bioactive insulin to permeate the jejunum. This has implications for the design of orally delivered particles that can release the payload when formulated with enhancers.
目前正在研究使用纳米载体实现口服肽递送。形成了胰岛素相关的阴离子聚电解质纳米颗粒复合物（PEC），其由透明质酸和壳聚糖以5:1的最佳质量混合比（MR 5）组成，随后用pH依赖性聚合物包衣。通过尺寸排阻色谱法将游离胰岛素与PEC分离，然后通过HPLC进行测量。胰岛素在PEC中的结合效率>95%，负载量约为83μg/mg颗粒。PEC的动态光散射和纳米颗粒跟踪分析显示多分散性低，zeta电位范围为-40至-50 mV，直径范围为95-200 nm。在模拟小肠液（FaSSIF-V2）中的溶解研究表明，PEC在胶体上是稳定的。用Eudragit L-100包衣的PEC在FaSSIF-V2中延迟了胰岛素释放，并比未包衣的PEC更能保护胰岛素免受胰蛋白酶攻击。未包衣的阴离子PEC在体外与粘蛋白的相互作用较弱，对Caco-2细胞无细胞毒性。包衣和未包衣的PEC均通过超滤进一步浓缩，在大鼠空肠灌注中允许给药50 IU/kg，但它们未能降低血糖或将胰岛素输送到血液中。当与渗透增强剂（PE）月桂酸蔗糖酯（100 mM）混合时，包衣PEC的物理化学参数相对不变，然而血糖降低了70%。总之，使用PE可使PEC释放的生物活性胰岛素渗透空肠。这对口服递送颗粒的设计具有启示意义，即与增强剂一起配制时可释放有效载荷。
