**9. Assays being developed/evaluated**

Another new approach to diagnosis of TB is biosensing technologies. Variety of portable, rapid, and sensitive biosensors with immediate "on-the-spot" interpretation have been de‐ veloped for MTB detection based on different biological elements recognition systems and basic signal transducer principles. Combination of nanotechnology and biosensing technolo‐ gy has very promising.

Transrenal DNA detection provides a challenging new target for molecular TB diagnosis. No commercial assays are currently available, largely due to the difficulties in the develop‐ ment of TB detection/read-out assays.

Combined high-resolution melting (HRM) curve analysis using a closed-tube RT-PCR is po‐ tentially an ideal screening method with a positive predictive value (PPV) of 100% and neg‐ ative predictive value (NPV) of at least 99.9%, for screening large specimen numbers in any TB laboratory.

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MTB urease is a bacterial virulence factor. Isotopcally labelled urea as substrate, Urea tracer has detected in exaled breath using portable infrared spectrofotometer. Signal correleted with bacterial load. [33]

A biophotonic detection platform has been developed that utilizes reporter enzyme fluores‐ cence to detect β-lactamase produced by MTB. This innovative new technology is now being adapted for point of care (POC) use [28]
