**4. Conclusions**

The present study demonstrates a new type of SERS platform based on woven wire mesh made of stainless steel (SSWM). The influence of the diameter of wires, their morphology and metal thickness on SERS efficiency was investigated and the optimal fabrication process parameters were established. In this paper, for the first time, we present the SERS substrate that exhibits excellent heat dissipation, which is a critical factor in SERS measurements of thermally sensitive samples. Our substrate enables generation of the high spectral resolution data even for very poorly scattering biological materials *via* safe adjustment of laser intensity to higher values. This approach overcomes the limitations associated with photo-and thermal degradation of sensitive materials, improves the spectral intensities of week Raman scatterers, and thus extends the rage of valuable SERS applications. In addition, the developed SERS substrate enables the detection and differentiation of Gram-positive and Gram-negative bacterial species in label-free manner, based on their high-quality spectral features.

**Supplementary Materials:** The following are available online at http://www.mdpi.com/2079-4991/8/9/663/s1.

**Author Contributions:** Conceptualization, T.S. and A.K., Data curation, E.W., Investigation, Z.M. and T.K and K.W., Methodology, K.N Validation, T.D., Writing original draft, A.K.

**Funding:** Foundation for Polish Science under gran<sup>t</sup> Team-Tech/2017-4/23.

**Conflicts of Interest:** The authors declare no conflict of interest.
