Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas - UNICAMP, Rua Monteiro Lobato, 255-Cidade Universitária, Campinas, São Paulo, 13083862, Brazil.
School of Veterinary Medicine, Federal University of Uberlândia, UFU, Uberlândia, Minas Gerais, Brazil.
Sci Rep. 2020 Jul 9;10(1):11341. doi: 10.1038/s41598-020-68247-0.
Topical anesthetics are widely applied in order to relieve the discomfort and anxiety caused by needle insertion and other painful superficial interventions at the oral cavity. So far, there are no commercially available effective topical anesthetic formulations for that purpose, and the most of developments are related to hydrophilic and low mucoadhesive forms. Therefore, we have prepared different hybrid nanofilms composed of biopolymer matrices (chitosan, pectin, and chitosan-pectin) blended with nanostructured lipid carriers (NLC) loading the eutectic mixture of 5% lidocaine-prilocaine (LDC-PLC), in order to fulfill this gap in the market. These dual systems were processed as hybrid nanofilms by the solvent/casting method, and its mucoadhesive, structural and mechanical properties were detailed. The most appropriate hybrid nanofilm combined the advantages of both pectin (PCT) and NLC components. The resultant material presented sustained LDC-PLC release profile for more than 8 h; permeation across porcine buccal mucosa almost twice higher than control and non-cytotoxicity against 3T3 and HACAT cell lines. Then, the in vivo efficacy of PCT/NLC formulation was compared to biopolymer film and commercial drug, exhibiting the longest-lasting anesthetic effect (> 7 h), assessed by tail flick test in mice. These pectin-based hybrid nanofilms open perspectives for clinical trials and applications beyond Dentistry.
局部麻醉剂被广泛应用于缓解口腔内针插入和其他浅表性疼痛干预引起的不适和焦虑。目前，尚无市售的有效局部麻醉制剂用于该目的，大多数开发都与亲水性和低粘膜粘附形式有关。因此，我们已经制备了不同的混合纳米纤维，由生物聚合物基质（壳聚糖、果胶和壳聚糖-果胶）与载有 5%利多卡因-丙胺卡因共晶混合物（LDC-PLC）的纳米结构化脂质载体（NLC）混合而成，以填补市场空白。这些双系统通过溶剂/浇铸法加工成混合纳米纤维，并详细研究了其粘膜粘附性、结构和机械性能。最适合的混合纳米纤维结合了果胶（PCT）和 NLC 成分的优点。结果材料呈现出超过 8 小时的 LDC-PLC 持续释放曲线；透过猪颊粘膜的渗透速度几乎是对照物的两倍，对 3T3 和 HACAT 细胞系无细胞毒性。然后，将 PCT/NLC 制剂的体内疗效与生物聚合物膜和商业药物进行比较，通过小鼠尾巴拍打试验评估，其表现出最长的麻醉效果（>7 小时）。这些基于果胶的混合纳米纤维为临床试验和牙科以外的应用开辟了前景。
