Need help with issueFieldMatch JQL function

[SWAPNIL SRIVASTAV]

I am trying to use this JQL for finding exact, case-sensitive match of the summary field. I had to use the regular expressions for same. But if we any brackets in the string, it query fails to find the issue. It is because the regular expression does not match the brackets Please let me know how can I do so.

JQL:
issueFunction in issueFieldMatch(\"project='Test' and issuetype ='Test Issue' and 'A Custom Field' =" + CustomFieldValue + "\", 'Summary', '^(?i)"+summaryStringValue+"\$') ORDER BY issuekey DESC"