Table 2.

A summary of various metabolites and the corresponding SERS detection enhancement substrates, assay, limit of detection (LOD) and dynamic range using SERS technique.

Metabolites		SERS Substrate	Assay Type	LOD	Dynamic range	Ref.
In Normal cells	Lactate	Fe3O4@Ag NPs	Droplet	10−14 ​M	10−14-5 ​× ​10−12 ​M	[91]
		Au@Ag NRs	Hydrogel	10−7 ​M	10−7-10−3 ​M	[93]
	ATP	Fe3O4@Ag NPs	Droplet	10−13 ​M	10−13-5 ​× ​10−11 ​M	[91]
	Pyruvate	Fe3O4@Ag NPs	Droplet	10−12 ​M	10−12-5 ​× ​10−10 ​M	[91]
In Cancer Cells	Kynurenine	Au NPs	Glass	10−6 ​M	10−6-10−4 ​M	[94]
	Tryptophan	Au NPs	Glass	10−6 ​M	10−6-10−4 ​M	[94]
In Cerebrospinal fluids	Glucose	Si foams with Raman reporters	Solution	4.7 ​× ​10−7 ​M	4.7 ​× ​10−7-10−4 ​M	[98]
In Blood	Lactic acid	Au NPs	Solution	10−5 ​M	10−5-3 ​× ​10−4 ​M	[99]
In Urine	Urea	Ag film	Silicon wafer	0.013 ​M	0.013–0.17 ​M	[101]
		Ag–Au compound NP film	Glass	10−3 ​M	10−3-0.02 ​M	[100]
	Creatinine	Au NPs	Solution	0.559 ​mg/mL	0.559–2.08 ​mg/mL	[102]
	Pregnane	Ag layer	Silica bead	10−14 ​M	10−14-10−4 ​M	[84]
In Fingerprints	Human IgG	Ag NPs	Glass	10−7 ​mg/mL	10−7-10−1 ​mg/mL	[123]
Cancer related metabolites	Pyrimidine and purine metabolites	Ag nanowires	Glass	1.77 ​× ​10−9 ​M		[105]
Drug metabolites	7-OH MTX	Ag NPs	Solution	2.87 ​× ​10−6 ​M		[109]
	DAMPA	Ag NPs	Solution	1.66 ​× ​10−6 ​M		[109]
	Opiods	Au nanoclusters	Solution	5 ​× ​10−11 ​mg/mL	5 ​× ​10−11-5 ​× ​10−6 ​mg/mL	[110]
	Paraxanthine	Ag NPs	Solution	1.5 ​× ​10−5 ​M		[114]
	Theobromine	Au colloid	Solution	5 ​× ​10−7 ​M	5 ​× ​10−7-10−5 ​M	[115]
	6-TUA	Ag colloid	Solution	10−6 ​M	10−6-10−3 ​M	[118]
	6-TGNs	Au NPs	Solution	10−8 ​M		[119]
	6-MMP	Au NPs	Solution	10−7 ​M		[119]
	Salicylic acid	Au NPs	Solution	3 ​× ​10−3 ​M	3 ​× ​10−3-0.01 ​M	[119]
	AMOZ	Au NPs	Nitrocellulose membrane	2.8 ​× ​10−10 ​mg/mL	2.8 ​× ​10−10-10−4 ​mg/mL	[121]