Applications of Raman-based techniques to on-site and in-vivo analysis

Raman-based technologies have proved to be excellent tools for on-site and in-vivo analysis, due to the non-invasive nature of their detection, their capability of providing structure information, their high tolerance to aqueous samples, the ultra-sensitivity of surface-enhanced Raman scattering (SERS) and resonance Raman scattering (RRS), the high spatial resolution of tip-enhanced Raman scattering (TERS), and the ultrashort spectra-acquisition time for coherent anti-Stokes Raman scattering (CARS) and stimulated Raman scattering (SRS).In this review, we highlight the recent success of Raman-based technologies in various applications, including:

• (1) 

  on-site surface analysis and chemical-reaction monitoring;

• (2) 

  on-site identification of cultural objects, archeological studies and planetary science;

• (3) 

  in-vivo analysis of cells and microorganisms;

• (4) 

  in-vivo diagnosis inside human and animal bodies;

• (5) 

  in-vivo fast Raman imaging and mapping;

• (6) 

  the study of SERS processes; and,

• (7) 

  assessment of nanomaterial safety.

     

HF molecules and poly(hydrogen fluoride) anions as ligands to metal centers

The paper is dealing with the two sets of the coordination compounds:

• (a) 

  the coordination compounds in which anhydrous HF is acting as a ligand to the metal ions

• (b) 

  the compounds in which poly(hydrogen–fluoride) anions of the type HnFn+1− (n = 1, 2, 3) are coordinated to the metal centers and connecting them in the 3D structures.

The main purpose of this work is the review of the above mentioned compounds which were recently isolated in our laboratory. The coordination of the metal centers and their connection in the three-dimensional network are illustrated with their crystal structures. A very brief review of the achievements of some other groups is also mentioned where it is appropriate.     

The oxidation of organic substances with compounds of trivalent manganese: XXI. The oxidation of glycoaldehyde with hexaquomanganese(III) ions in a noncomplexing perchloric acid medium

The oxidation of glycolaldehyde with hexaquomanganese(III) ions in a noncomplexing perchloric acid medium was studied. The optimum conditions have been found for analytical use of the reaction. The recommended procedure is based on the oxidation of the test substance with the oxidant in the absence of atmospheric oxygen and back-titration of the unconsumed reagent with ferrous sulfate.

2. Accuracy and Reproducibility of the Determination of Glycolaldehyde with Hexaquomanganese(III) Ions in a Noncomplexing Perchloric Acid Medium

Taken (μg)	Found (μg)a	Standard deviation (μg)
751	748	12
1501	1485	15
2252	2192	7

a

The values are the average of seven determinations, from which the standard deviation value was calculated.

     

The oxidation of organic substances with compounds of trivalent manganese: XVIII. A contribution to the coulometric generation of manganese(III) acetate in an acetic acid medium

Conditions were found under which manganese(III) acetate can be electrochemically generated at a platinum anode with 100% current efficiency. It was found that even traces of

5. Time Dependence of the Consumption of the Oxidizing Reagent in the Indirect Determination of Hydroquinone with Coulometric Generated Manganese(III) Acetate

     

14.

CaO solubility and activity coefficient in molten salts CaCl₂–x (x = 0, NaCl, KCl, SrCl₂, BaCl₂ and LiCl)     

Shulan Wang  Fusheng Zhang  Xuan Liu  Lijun Zhang 《Thermochimica Acta》2008,470(1-2):105-107

CaO solubility in equimolar molten salts CaCl₂–x (x = 0, NaCl, KCl, SrCl₂, BaCl₂ and LiCl) was determined at 873–1223 K and activity coefficient calculated. CaO solubility in the binary salts is less than in CaCl₂, and the activity coefficient is greater than one. With increasing temperature CaO solubility increases and the activity coefficient decreases. The dependency of CaO activity coefficient on temperature in equimolar molten salts CaCl₂–x is

Time (min)	0	5	10	30	60
Consumption of Mn(III) (mol/mol)	2.00	1.99	2.00	2.01	2.00

CaCl2	RTln γCaO = 6961 + 5.06 T (K)	1123–1223 K
CaCl2–NaCl	RTln γCaO = 3985 + 17.67 T (K)	923–1123 K
CaCl2–KCl	RTln γCaO = 2384 + 22.72 T (K)	1073–1223 K
CaCl2–SrCl2	RTln γCaO = 27245–1.13 T (K)	1073–1223 K
CaCl2–BaCl2	RTln γCaO = 17068 + 10.19 T (K)	1223–1273 K
CaCl2–LiCl	RTln γCaO = 14724 + 0.72 T (K)	923–1073 K

Full-size table

CaO solubility and activity coefficient in molten salts CaCl2–x (x = 0, NaCl, KCl, SrCl2, BaCl2 and LiCl)

CaO solubility in equimolar molten salts CaCl₂–x (x = 0, NaCl, KCl, SrCl₂, BaCl₂ and LiCl) was determined at 873–1223 K and activity coefficient calculated. CaO solubility in the binary salts is less than in CaCl₂, and the activity coefficient is greater than one. With increasing temperature CaO solubility increases and the activity coefficient decreases. The dependency of CaO activity coefficient on temperature in equimolar molten salts CaCl₂–x is

Polarographic determination of antimony in leadantimony alloys

A polarographic method for the determination of antimony in lead-antimony alloys has been developed. It was found that the interference due to the presence of varying concentrations of lead and hydrochloric acid would be eliminated by the addition of potassium chloride.

t001. The method gave satisfactory results within the range:

     

16.

Spectrophotometric studies of neomycin-copper complex and determination of neomycin sulfate using an auxiliary ligand     

J.K. Agrawal  S.G. Harmalkar  R. Vijayavargiya 《Microchemical Journal》1976,21(2):202-208

Spectrophotometric investigation of the deep blue colored, water-soluble complex of

1. Stability constant and free energy of formation of Cu-NMS complex at 30 ± 1 °C

Hydrochloric acid	4 — 8M
Lead	0 — 0.03M
Antimony	0 — 0.002M

     

17.

A new kinetic method for the determination of magnesium and its application to natural waters     

M. Ternero  F. Pino  D.Pérez Bendito  M. Valcárcel 《Microchemical Journal》1980,25(1):102-110

A kinetic method is described for the determination of trace amounts of magnesium in the presence of calcium. The procedure is based on the inhibition of the manganese(II) catalyzed aerial oxidation of 1,4-dihydroxyphthalimide dithiosemicarbazone reaction by

2. Effect of Transition Metals^a

Method	$\text{log}\text{K}{}_{\mathrm{s}}$	ΔF (Kcal/mole)
Mukherji and Dey (4)	4.11	?5.70
Subhrana and Raghavrao (6)	4.80	?6.66

Transition metal	Concentration (M)	Percentage inhibition	Mg(II) found (×l05M)
Fe(II)	3.6.10?5	54.1	4.62
Fe(III)	3.6.10?5	47.8	4.48
Co(II)	3.4.10?5	50.0	4.53
Ni(II)	3.4.10?5	50.0	4.53
Cu(II)	3.1.10?5	52.0	4.56
Zn(II)	3.0.10?5	54.1	4.62
Cd(II)	1.7.10?5	52.0	4.56
Hg(II)	9.9.10?6	45.8	4.44
Sn(II)	2.1.10?6	50.0	4.52
Pb(II)	1.2.10?6	54.1	4.62

a

Conditions: 4.53.10^?5M Mg(II), 35 ng Mn ml^?1, 0.429 M ammonia, 1.6.10^?4M OH-PDT.

3. Determination of Magnesium in Natural Waters

			Mg(II) found (M)b
Natural water	Ca(II) presenta		Atomic absorption
sample	M	Kinetic absorption	method
Commercial	3.45 · 10?4	1.65 · 10?3	1.74 · 10?3
Commercial	5.46 · 10?4	1.57 · 10?4	1.81 · 10?4
Untreated	6.13 · 10?4	2.16 · 10?4	2.40 · 10?4
Treated	4.95 · 10?4	1.93 · 10?4	2.17 · 10?4

a

EDTA titration less the magnesium.

b

Average of three separate determinations. traces of magnesium(II). The reaction is followed spectrophotometrically by measuring the rate of change in absorbance at 594 nm. The calibration graph (percentage inhibition vs magnesium concentration) is linear in the range 329–535 · 10^?5M with an accuracy and precision of 1.2%. The method has been applied to the determination of magnesium in natural waters at low concentrations.

     

Spectrophotometric studies of neomycin-copper complex and determination of neomycin sulfate using an auxiliary ligand

Spectrophotometric investigation of the deep blue colored, water-soluble complex of

1. Stability constant and free energy of formation of Cu-NMS complex at 30 ± 1 °C

A new kinetic method for the determination of magnesium and its application to natural waters

A kinetic method is described for the determination of trace amounts of magnesium in the presence of calcium. The procedure is based on the inhibition of the manganese(II) catalyzed aerial oxidation of 1,4-dihydroxyphthalimide dithiosemicarbazone reaction by

2. Effect of Transition Metals^a

Ion flotation of cadmium using ethylhexadecyldimethylammonium bromide

Cadmium ions react with the collector, ethylhexadecyldimethylammonium bromide (EHDABr), to form a surface-active sublate which can be removed from aqueous bromide

a. Effect of Foreign Metal Ions on the Flotation of Cadmium^a

Foreign ion	Foreign ion concentration (M) (×10?5)	Foreign ion removed (%)	Cadmium removed (%)
None			99.21
Zn2+	6.11	0.06	98.41
Cu2+	6.29	3.64	97.80
Pb2+	3.86	4.80	91.78
Cr6+	7.69	30.75	99.07 solutions by ion flotation. A typical ion flotation procedure involves passing air through a 250-ml solution containing 5 ppm Cd2+, 0.05 M Br?1, and 1.7 × l0?3M EHDABr at a flow rate of 40 ml/min for 1 hr. The procedure was simple and efficient. Chromium, copper, and zinc ions do not interfere under the experimental conditions.

a

Cd²⁺, 4.46 × 10^?5M; EHDABr, 4.25 × 10^?4; Br^?, 5 × 10^?2M; flow rate, 40 ml/min; time, 60 min.

     

Spectrophotometric determination of sulfite with soluble mercury(II) compounds

Sulfite ion reacts with mercury(II) ion in acid solution to form the mercury(I) ion. The reaction is rapid and quantitative. The mercury(I) ion absorbs at 237 nm with a molar

5. Beer's law Data for Sulfite Complexes of Covalent Mercury(II) Compounds

SO2 (ppm)	?HgCl2a	?HgBr2	?Hg(Ac)2b	?Hg(SCN)2
2.0	12,500	10,000	10,000	9,200
4.0	12,500	11,500	10,000	9,000
6.0	12,500	11,500	10,000	9,200
8.0	12,000	11,000	10,500	9,800

a

Molar absorptivity based on sulfite ion at 230 nm. Solution was 6.86 buffer.

b

Mercuric acetate solutions seemed to be somewhat unstable. absorptivity of about 25,000. The absorbance is linear over a range of approximately 0.5–5.0 ppm as SO₂. Covalent mercury(II) compounds form a complex with sulfite, Hg(SO₃)₂^2?, which absorbs at 230 nm and shows a linear response over a range of 1–8 ppm as SO₂.

     

Spectrofluorimetric determination of thallium in silicate rocks with rhodamine b in the presence of aluminum chloride

A sensitive spectrofluorimetric procedure with rhodamine B in the presence of aluminum chloride is given for determining submicrogram and microgram quantities of thallium in silicate rocks. Samples are decomposed with a mixture of hydrofluoric and nitric acids and then treated with hydrochloric acid. Thallium is extracted as its dithizonate with chloroform from an alkaline medium containing ascorbate, citrate, and cyanide and then back-extracted with dilute nitric acid. After destruction of the organic matter and treatment with bromine, hydrochloric acid, aluminum chloride, and rhodamine B, the

T001. Determination of thallium in U.S. Geological Survey standard rocks by different laboratories

Thallium (p.p.m.)		Method	Ref.
G-1	W-1
1.06	0.102	Neutron activation analysis	1
1.08	0.121, 0.116	Neutron activation analysis	2
1.3	0.17	Neutron activation analysis	3
1.3	0.11	Spectrographic	4
	0.105–0.110	Flameless atomic absorption spectroscopy	5
1.3a	0.13a		19
1.24b	0.110b		20
1.09 ± 0.01	0.110 ± 0.005	Spectrofluorimetric	Present method

a

Values given by Fleischer.

b

Average value given by Flanagan. fluorescence intensity of the benzene-extracted rhodamine B chlorothallate is measured. The limit of determination is approximately 0.01 p.p.m. for a 1.0-g sample. The thallium contents of U.S. Geological Survey standard rocks G-1 and W-1 were found to be 1.09 ± 0.01 and 0.110 ± 0.005 p.p.m., respectively.