Table 4 Combined analysis of organic and inorganic gunshot residues using instrumentation technique

Gas chromatography

Toal et al., (2014)

NG, TNT, RDX, PETN

NG—10 ng, TNT—10 ng, RDX—10 ng, PETN—0.5 ng

Less than 20min

1. Major advantage of the technique is when combined with MS, SEM-EDx, TEA, etc. will able to detect organic as well as inorganic residues present in GSR.

2. Another advantage is its capability of detecting compounds of interest in nanogram level.

1. Major drawback of the method is its inability to analyze Nitrocellulose as it not much volatile.

Roberts et. al (2015)

NG, DNT, DPE

0.34–1.4 mM

Less than 25min

(Wu et al., 2001)

4-NDPA, 2-NDPA, 2,4-2NDPA, DPA, N-NDPA

0.05–1 ng

Less than 10min

Moran et.al (2014)

DPA, 2-NDPA, 4-NDPA, DMP, EC

–

–

Mach et.al (1978)

EC, NG, DPA, DNT,DP

–

–

High-pressure liquid chromatography

Gassner et.al (2016)

AKII, MC, N-N-DPF, EC, DPA, 2-NDPA, 4-NDPA, N-NDPA

0.005–3.5 ng/ml

Less than 7 min

1. Advantage in using the technique is for analyzing OGSR with various types of detector.

2. Another advantage is its high reproducibility, sensitivity and give stable result.

1. Major drawback of this method is that it can detect organic components with more positive results in spite of inorganic residues.

Laza et.al (2007)

DPA, AKII, 2-NDPA, EC, MC

In nanogram quantity

Less than 10 min

Taudte et. al (2016)

32 organic constituents

0.03–0.2 ng

27 min

Xu et. al (2004)

21 nitroaromatics, amines and some Nitric Esters

0.012–1.2 ng

–

Maitre et.al (2018)

NDPA, DPA, MC, EC

0.01–5 ppm

Less than 20min

Capillary electrophoresis

Mac Creehan et.al (1998)

NG, NB, 2,4-DNT, 2,6 DNT, DPA, EC

–

Less than 15 min

1. The advantage of the technique is that it is rapid, with high-resolution separation of complex mixture.

2. Another advantage is when combine with ME than electrically neutral compound can also be separated.

1. Major drawback of the method is its poor detection limit for some compounds.

Reardon et.al (2001)

NG, DPA, N-NDPA, EC

–

–

Northop et.al (2001)

NG, DPA, DNT

–

–

Thin-layer chromatography

Meng et.al (1994)

EC, NC, NG

–

–

1. Major advantage of using the technique is its ability to detect residues in ppb and ppt levels.

1. Major drawback of this technique is it depends on the volatility and polarity of the molecule to be detected.

2. Only applicable to detect the organic constituents [resent in GSR.

Leggett et. al (1989)

NC

–

–

Raman spectroscopy

Lopez et.al (2016)

DPA, NC, N-NDPA, 2-NDPA,4-NDPA, EC

–

Less than 60 min

1. Main advantage of this technique is its non-destructive nature.

2. Another advantage of the technique is its ability to detect both organic and inorganic residues present in GSR sample.

1. Major drawback of the method is its low sensitivity and cannot be applied for trace constituent’s level analysis.

Khandasammy (2019)

Organic constituents

–

–

Neutron activation analysis

Chohra et. al (2015)

Pb, Ba, Br, Sb, Sn, Cr, Ti, Fe, Bi, Zn, Na

–

2 h

1. The method helpful for quantitative and qualitative analysis for elemental detection.

2. The method is extremely sensitive and accurate and can detect element in pico- and nanogram quantity.

1. Major disadvantage of the method is it require access to research nuclear reactor.

2. The instrument require huge amount of sample and require specialized personnel for handling it.

Merle et.al (2016)

Ba, Sb

0.005–50.31 μg

12 h

Gibelli et.al (2010)

Sb

0.07–13.89 μg

–

Ruch et.al (1964)

Ba, Sb

0.05–10 μg, 0.01–0.03 μg

–

Pillay et.al (1974)

Ba, Sb, Cu, Au

0.01–1.085 μg

–

Atomic absorption spectroscopy

Yukshel et.al (2016)

Pb, Sb, Ba

35–800 ng per swab

–

1. Major advantage of this technique is the applicability in the detection of Ba²⁺, Pb²⁺, Sb³⁺ in nano- and picogram quantity.

2. Another advantage of this technique is that it gives 90% of positive results.

1. Major drawback of this technique is its heavy cost and require highly specialized personnel for handling.

2. Another disadvantage of this method is it require huge amount of sample for detecting the metal constituents

Raver by et.al (1982)

Tin

–

–

Koon et. al (1987)

Sb, Ba

–

–

Inductively coupled plasma spectroscopy

Koon et. al (1988)

Ba, Pb, Sb

0.5–1.4 ng

–

1. The technique is for bulk analysis to detect all the 3 major inorganic residues even in trace levels.

2. Result obtained with this technique is positive in 80–90% of cases

1. Major disadvantage of this technique is that it require more amount of sample for analysis.

2. The technique is non-destructive, time consuming and require highly specialized personnel for handling the instrument

Costa et.al (2016)

Pb, Ba, Sb, Al, Ti, Cr, Mo, Cu, Zn, Sr

0.119–10.9 ng/ml

–

Diaz et.al (2012)

Pb, Ba, Sb

0.002–58.928 μg/m³

–

Lagoo et.al (2010)

–

0.04–2.3 μg

–

Halim et. al (2013)

Pb, Ba, Cu

0.098–0.47 μg/ml

–

Reardon et al., (2001)

Ba, Cu, Pb, Sb

0.19–1.72 μg

–

Krishnan, (1974)

Sb, Ba, Pb

–

–

Sarkis et.al (2007)

Sb, Ba, Pb

–

–

Reiss et al., (2003)

Sb, Ba, Pb

Less than 1 μg/l

–

Scanning Electron Microscopy (SEM)

French et al., (2014)

–

0–591 particles

–

1. The method is applied to detect the morphological feature of particle.

2. Along with morphological feature EDx give the elemental analysis too.

1. Major disadvantage of the technique is the cost of instrument and time consuming nature.

2. Another disadvantage is that the cigarette lighter particle are same as GSR in morphology which can cause interference in the study.

Lindsay et al., (2011)

Pb, Ba, Sb

150–4486 particles

–

Wrobel et al., (1998)

Al, Si, Ca, S, K, Cl, P, Na

–

–

De Gaetano et al., (1992)

Pb, Ba, Sb, Zn, Cu

1–7 particles

60 min

Toal et al., (2014)

Ba, Sb, Sn, Zn, Al, W, S

–

–

Brozek-Mucha, (2007)

Pb, Ba, Sb, Sn

100–4000 particles

–

Brozek-Mucha, (2009)

Pb, Ba, Sb

21–185 particles

–

Gerard et al., (2011)

Pb, Ba, Sb

–

–

French & Morgan, (2015)

Pb, Ba, Sb

14–443 particles

–

Brozek-Mucha

Pb, Ba, Sb, Sn

1–70 particles

–

Kara (2017)

Pb, Ba, Sb

1603–3911 particles

–

Rijnders et al., (2010)

Pb, Ba, Sb, Ti, Zn

5–894 particles

–

Brozek-Mucha & Jankowicz, (2001)

Pb, Ba, Sb, Cu

50–7000 particles

–

Izzharif et al., (2010)

Pb

–

–

Greely & Weber, (2017)

Pb, Ba, Sb, Sn

0–357 particles

–

Charles et al., (2013)

Pb, Ba, Sb

3–167 particles

–

Schwartz & Zona, (1995)

Pb, Ba, Sb

11–542 particles

–

Reyes et al., (2018)

Pb, Ba, Sb

13–756 particles

–

Kara (2017)

Pb, Ba, Sb

43–279 particles

–

Charles & Geusens, (2012)

Pb, Ba, Sb, Ti, Zn

0–1550 particles

–

Gerard et al., (2011)

–

0–36 particles

–

Fojtasek & Kmjec, (2005)

Pb, Ba, Sb

0–3020 particles

–

Jalanti (1999)

Pb, Ba, Sb

0–187 particles

–

Romano (2020)

Pb, Ba, Sb, Zn, Ti, Ca, Cu, K, P, S, Mg

5–40 particles

–