There are many proteins and enzymes in the human body, and their dysfunction can lead to the emergence of a disease. The use of proteins as a drug is common in various diseases such as diabetes. Proteins are hydrophilic molecules whose spatial structure is critical to their correct function. There are different ways for the administration of proteins. Protein structures are degraded by gastric acid and enzymes in the gastrointestinal tract and have a slight ability to permeate from the gastrointestinal epithelium due to their large hydrophilic nature. Therefore, their oral use has limitations. Since the oral route for the administration of drugs is one of the best and easiest routes for patients, many studies have been done to increase the stability, penetration, and ultimately, the bioavailability of proteins through oral administration. One of the studied strategies for oral delivery of protein is the use of pH-sensitive polymer-based carriers. These carriers use different pH-sensitive polymers, such as eudragit®, chitosan, dextran, and alginate. The use of pH-sensitive polymer- based carriers by protecting the protein from stomach acid (low pH) and degrading enzymes, increasing permeability and maintaining the spatial structure of the protein, leads to increased bioavailability. In this review, we focus on the various polymers used to prepare pH-sensitive polymer- based carriers for the oral delivery of proteins.

人体内有许多蛋白质和酶，它们的功能失调会导致疾病的出现。蛋白质作为药物的使用在糖尿病等各种疾病中很常见。蛋白质是亲水分子，其空间结构对其正确功能至关重要。蛋白质的给药有不同的方法。蛋白质结构在胃肠道中被胃酸和酶降解，并且由于其大的亲水性而具有从胃肠上皮渗透的轻微能力。因此，它们的口服使用具有局限性。由于药物给药的口服途径是患者最好和最简单的途径之一，因此已经进行了许多研究以通过口服给药来增加蛋白质的稳定性、渗透性，并最终提高蛋白质的生物利用度。口服递送蛋白质的研究策略之一是使用基于 pH 敏感的聚合物载体。这些载体使用不同的 pH 敏感聚合物，例如 eudragit®、壳聚糖、葡聚糖和藻酸盐。通过保护蛋白质免受胃酸（低 pH）和降解酶的影响，增加渗透性和维持蛋白质的空间结构，使用基于 pH 敏感聚合物的载体，导致生物利用度增加。在这篇综述中，我们重点关注用于制备 pH 敏感性聚合物基载体的各种聚合物，以用于口服递送蛋白质。通过保护蛋白质免受胃酸（低 pH）和降解酶的影响，增加渗透性并保持蛋白质的空间结构，使用基于 pH 敏感聚合物的载体，导致生物利用度增加。在这篇综述中，我们重点关注用于制备 pH 敏感性聚合物基载体的各种聚合物，以用于口服递送蛋白质。通过保护蛋白质免受胃酸（低 pH）和降解酶的影响，增加渗透性并保持蛋白质的空间结构，使用基于 pH 敏感聚合物的载体，导致生物利用度增加。在这篇综述中，我们重点关注用于制备 pH 敏感性聚合物基载体的各种聚合物，以用于口服递送蛋白质。