Laser-Induced Breakdown Spectroscopy (LIBS) for Trace Element Detection: A Review

Table 3

LIBS conditions and corresponding LoDs of trace elements in foods.

Method	Description of laser	Sample materials	Trace element	LoD (ppm)	Reference
LIBS	Q-switch Nd:YAG laser, 1,064 nm, 650 mJ, 7 ns, 10 Hz	Spinach	Mg II; Ca I; Na I; K I	29.63; 102.65; 36.36; 44.46	[120]
		Unpolished rice	Mg II; Ca I; Na I; K I	7.54; 1.76; 4.19; 6.70
LIBS and ICP-MS	Q-switch Nd:YAG laser, 266 nm, 8 ns, 15∼18 mJ, 10 Hz	Dates	Mg I	6	[130]
			Ca I	17
			Cr I	1
LIBS	Q-switch Nd:YAG laser, 1,064 nm, 40 mJ, 8 Hz, 650 ns, 1.05 ms	White chickpea	Ti	33.9	[131]
LIBS	Q-switch Nd:YAG laser, 1,064 nm, 0∼100 mJ,: 0∼2 μs, 50∼250 μm, 5 Hz	Flour samples	Ca	45–80	[132]
			K	105–200
			Mg	25–60
LIBS and ICP-MS	Q-switch Nd:YAG laser, 266 nm, 30 mJ, 8 ns, 20 Hz	Tea samples	Fe	22	[133]
			Cr	12
			K	14
			Br	11
			Cu	6
			Si	1
			Ca	12
LIBS and EDXRF	Q-switch Nd:YAG laser, 1,064 nm, (365 ± 3) mJ, 5 ns	Wheat flour	P I	40	[134]
			K I	1200
			Ca II	17
			Mg I	10
			Fe II	0.7
			Mn II	0.5
			Zn II	1.0
			Cu I	0.5
Nanoparticle-enhanced LIBS	Q-switch Nd:YAG laser, 1,064 nm, 160 mJ, 3–5 ns, 0.2 μs	Fruits and vegetables	PI (213.62 nm)	0.019	[135]
			PI (214.91 nm)	0.015
			PI (253.56 nm)	0.009
			PI (255.33 nm)	0.029
			Cd I (214.4 nm)	0.0016
LIBS	Q-switch Nd:YAG laser, 1,064 nm, 950 mJ, 5 ns, 2.0 μs, 1∼10 Hz	Cucurbit seeds (pumpkin, ash gourd, watermelon, muskmelon)	Mg II	5, 12, 3.4, 3.2	[136]
			Ca II	26.6, 35.8, 18.1, 28.2
			Na I	44.2, 43.9, 47.9, 36.8
			K I	21.9, 21.1, 29.3, 37.9
LIBS	Q-switch Nd:YAG laser, 532 nm, 1 Hz, 14 mJ/pulse, 1 Hz	Bakery products (bread)	Nacl Na	175 69	[137]
LIBS	Q-switch Nd:YAG laser, 1,064 nm, 150 mJ, 5 ns	Infant formula	Ca	3,690	[138]
LIBS	Q-switch Nd:YAG laser, 1,064 nm, 50 mJ, 8 ns	Breakfast cereals	Ca	9.5	[139]
LIBS	Q-switch Nd:YAG laser, 1,064 nm, 400 mJ, 8 ns, 10 Hz	Mochi (Japanese rice cake)	Cu	0.1	[140]