Azure blob storage SDK set Content-Type using php

Can't find some example that set blob's Content-Type from official site.

Here is example code.

<?php
    require_once(__DIR__ . '/autoload.php');

    use MicrosoftAzure\Storage\Blob\BlobRestProxy;
    use MicrosoftAzure\Storage\Blob\Models\CreateBlockBlobOptions;

    // declaration variables
    $connectionString = 'INPUT_YOUR_SECRET_KEY';
    $containerName = 'testContainer';
    $blobName = 'blob.json';
    $content = '{"nopsled":"blog"}';
    $blobContentType = 'application/json; application/json; charset=UTF-8';

    $blobClient = BlobRestProxy::createBlobService($this->connectionString);

    $options = new CreateBlockBlobOptions();
    $options->setContentType($blobContentType);
    $blobClient->createBlockBlob($containerName, $blobName, json_encode($content, JSON_UNESCAPED_UNICODE), $options);
    // json_encode korean language using by JSON_UNESCAPED_UNICODE