Berberine hydrochloride is a natural alkaloid with a wide range of therapeutic applications, including antimicrobial [
1,
2,
3,
4], anti-inflammatory [
5], anticancer [
6,
7,
8,
9], and antidiabetic effects [
10]. Despite its potential, the clinical use of BBH has been severely limited by its low solubility and stability, particularly when administered orally [
11,
12,
13]. These challenges require the development of innovative drug delivery systems to improve their bioavailability and therapeutic efficacy [
14,
15]. Hydrogels have emerged as a promising solution for drug delivery, capable of improving the solubility and stability of hydrophobic drugs [
16,
17]. Among the different hydrogel forming materials, chitosan and carboxymethyl-β-cyclodextrin deserve special attention ([
18]). Chitosan is a biocompatible polymer with excellent film forming properties, while CMCD is known for its ability to form inclusion complexes with hydrophobic molecules, thereby improving their solubility [
19]. Chitosan cross-linked with β-cyclodextrin forms a chitosan hydrogel, making it a good carrier for poorly water-soluble drugs [
20]. β-Cyclodextrin is a cyclic oligosaccharide composed of seven glucose units [
21,
22]. It has a hydrophobic internal cavity and a hydrophilic external surface, allowing it to form inclusion complexes with hydrophobic drugs, such as BBH [
23,
24]. β-Cyclodextrin can improve the solubility, stability and bioavailability of poorly soluble drugs by encapsulating them in its cavity [
25,
26]. By combining the advantages of chitosan and β-cyclodextrin, a physically cross-linked CS/CMCD hydrogel can be developed as an effective carrier for BBH [
27]. The physical cross-linking between CS and CMCD allows easy fabrication of hydrogels without the need for chemical cross-linkers, thereby preserving the biocompatibility and bioactivity of the encapsulated drug [
28]. The hydrogel matrix can provide sustained release of BBH, ensuring a prolonged therapeutic effect and minimizing the frequency of administration [
29]. Several studies have explored the application of CS/β-cyclodextrin hydrogels as drug carriers, demonstrating their potential to improve drug delivery [
30,
31]. For example, Hui et al. developed a BBH-loaded chitosan/β-cyclodextrin hydrogel that showed improved solubility, sustained release, and enhanced antibacterial activity [
31]. Another study by Lin et al. investigated a nanocellulose/β-cyclodextrin hydrogel for ocular delivery of BBH, which exhibited sustained drug release and improved therapeutic efficacy [
32]. Tsai et al. investigated chitosan/β-cyclodextrin hydrogels for transdermal delivery of BBH and showed that the hydrogel formulation effectively improved therapeutic outcomes in a mouse model of psoriasis, indicating its potential as a delivery system. transdermal administration for BBH [
30,
33]. Therefore, physically cross-linked hydrogels are more favorable for biomedical applications, including drug delivery systems [
34,
35]. In this study, we developed an oral, physically cross-linked hydrogel formulation of BBH by loading it onto a CS/CMCD hydrogel matrix. Our results showed that the physical cross-linking interaction between CS and CMCD leads to the formation of stable complexes. This approach exploits the solubility-enhancing properties of CMCD as well as the biocompatibility and stability offered by chitosan. The resulting hydrogel formulation not only significantly increases the solubility of BBH, but also ensures its sustained release and improved bioavailability, thereby addressing the major limitations of free BBH in oral administration. Our results demonstrate the superior performance of this innovative formulation compared to free BBH.