What is the corresponding web3 type to solidity bytes when using Typescript?

I want to call a solidity function a passing a parameter bytes b.

function xyz(address a, bytes hexData)

We front end code in Typescript is like that

if (hexData) {

    let hexDataInBytes = Web3Utils.hexToBytes(hexData);
    console.log("hexDataInBytes "); 
    console.log(hexDataInBytes); 

    this.getAccounts().then(accounts => {
            let selectedAccount = accounts[0];
            let contract =  this.createContract(addr);

            contract.instance.methods.xyz(toAddress, hexDataInBytes)
            .send ({ from:selectedAccount, gas:500000 })
            .then (result => fSucess(result))
            .catch (error => fError(error));
        }); 

}

Passing hexData = 0x0123, I got hexDataInBytes = [1,35].
However, I got the error

RROR Error: Uncaught (in promise): Error: Given parameter is not bytes: “1,35”
Error: Given parameter is not bytes: “1,35”
at SolidityTypeDynamicBytes.formatInputDynamicBytes [as _inputFormatter] (formatters.js:83)
at SolidityTypeDynamicBytes.SolidityType.encode (type.js:188)
at eval (index.js:255)

So, what is the correct way to call this function xyz?

Thank you!

contract.instance.methods.xyz(toAddress, 0x0123)