This study evaluates the current state of blockchain interoperability by analyzing existing cross-chain solutions and their effectiveness in securely transferring digital assets across different blockchain networks. The primary objective is to identify technologies that enable secure and efficient cross-chain transfers, with a focus on the ERC-1155 standard. Through an in-depth analysis, the paper highlights key challenges in interoperability between private-to-public and private-to-private blockchains. Additionally, advanced cryptographic techniques, particularly Zero-Knowledge Proofs are examined for their role in enhancing privacy, security, and transaction validation. As part of this research, a custom relayer was developed, successfully bridging token transfers between private and public blockchains using zk-SNARKs. This implementation shows the feasibility of secure, privacy-preserving cross-chain transactions, contributing to the ongoing development of interoperability standards in private-to-public networks.