biostudies-literatureUnknown11(9)Li YInsulin, a peptide hormone, is one of the most common and effective antidiabetic drugs. Although oral administration is considered to be the most convenient and safe choice for patients, the oral bioavailability of insulin is very low due to the poor oral absorption into blood circulation. Intestinal epithelium is a major barrier for the oral absorption of insulin. Therefore, it is vital to develop intestinal permeation enhancer to increase the antidiabetic efficacy of insulin after oral administration. <b>Methods:</b> Charge-switchable zwitterionic polycarboxybetaine (PCB) was used to load insulin to form PCB/insulin (PCB/INS) particles through the electrostatic interaction between positively charged PCB in pH 5.0 and negatively charged insulin in 0.01 M NaOH. The opening effect of PCB/INTheranostics4452-4466https://www.ebi.ac.uk/biostudies/studies/S-EPMC7977443biostudies-literatureCharge-switchable zwitterionic polycarboxybetaine particle as an intestinal permeation enhancer for efficient oral insulin delivery.PMC7977443Peng HLi YYang JZhang TJi WZhao RLu ZZhang XLiu RfalseCharge-switchable zwitterionic polycarboxybetaine particle as an intestinal permeation enhancer for efficient oral insulin delivery.Insulin, a peptide hormone, is one of the most common and effective antidiabetic drugs. Although oral administration is considered to be the most convenient and safe choice for patients, the oral bioavailability of insulin is very low due to the poor oral absorption into blood circulation. Intestinal epithelium is a major barrier for the oral absorption of insulin. Therefore, it is vital to develop intestinal permeation enhancer to increase the antidiabetic efficacy of insulin after oral administration. <b>Methods:</b> Charge-switchable zwitterionic polycarboxybetaine (PCB) was used to load insulin to form PCB/insulin (PCB/INS) particles through the electrostatic interaction between positively charged PCB in pH 5.0 and negatively charged insulin in 0.01 M NaOH. The opening effect of PCB/IN2021-01-01T00:00:00Z20212025-04-25T18:39:06.419Z2025-04-06T07:41:23.29ZS-EPMC79774433375407110.7150/thno.54176