What is green analytical chemistry?The goal of green analytical chemistry is to use analytical procedures that generate less hazardous waste and that are safer to use and more benign to the environment.

developing new analytical methodologies modifying an old method to incorporate

procedures that either use less hazardouschemicals or use lesser amounts of hazardouschemicals.

Greening Pretreatment

1. Ultrasound

2. Microwave-Assisted Extraction (MAE)

3. Supercritical Fluid Extraction (SFE) and Superheated

Water Extraction (SWE)

4. Membranes

5. Cloud Point Extraction (CPE)

6. Greening through Screening

7. Solid-phase extraction (SPE)

8. Solid-phase micro extraction (SPME)

Solid-phasemicroextraction (SPME)

SPME PrinciplesA simple, effective adsorption/ desorption

technique• In SPME a small amount of extracting phase (fiber

coating) associated with a solid support is placed in

contact with the sample matrix for a predetermined

amount of time. If the time is long enough, a

concentration equilibrium is established between

the sample matrix and the extraction phase.

• After extraction, SPME fiber is transferred to the

injection port of separating instruments, like GC or

HPLC, where desorption of the analyte takes place

and analysis is carried out.

Three Basic Types of Extractions1- Direct Immersion SPME In DI-SPME, the fiber is

directly immersed in liquid samples.

2- Head Space SPME In HS-SPME, the fiber is

exposed in the vapor phase above a gaseous, liquid

or solid sample.

3- Membrane-Protected SPME Indirect SPME

extraction through a membrane The main purpose:

protecting the fiber against damage

Extraction Time• The extraction time depends on the size of the

compounds, fiber coating, type of extraction

used and sample concentration.

• Extraction times can be shorter when you are:

1- analyzing small compounds (<150 MW)

2- using thinner, absorbent type fiber coatings

3- using the headspace technique

4- working with high concentration samples (high ppb or

ppm range).

Extractions typically take 15-20 minutes.

Extraction Temperature• It is critical for accurate quantitation of the sample.

• The use of heat during headspace SPME will help

release the analyte from the sample, improve

sensitivity, and shorten the extraction time.

• it must use a constant temperature for all extractions

to obtain good precision.

Application of SPME in various fields ofanalytical chemistry

• Environmental applications

• Applications in food chemistry

• Analysis of wines and other alcoholic beverages

• Application to biological fluids

• Hair analysis

• Breath analysis–volatile metabolites of microorganisms

1. Direct analytical techniques should be applied to avoid sample treatment.2. Minimal sample size and minimal number of samples are goals.3. In situ measurements should be performed.4. Integration of analytical processes and operations savesenergy and reduces the use of reagents.5. Automated and miniaturized methods should be selected.6. Derivatization should be avoided.7. Generation of a large volume of analytical wasteshould be avoided and proper management ofanalytical waste should be provided.8. Multi-analyte or multi-parameter methods arepreferred versus methods using one analyte at atime.9. The use of energy should be minimized.10. Reagents obtained from renewable sourceshould be preferred.11. Toxic reagents should be eliminated or replaced.12. The safety of the operator should be increased.

The proposed green RP-HPLC method was validated according to ICH guidelines for the linearity, selectivity, accuracy hydrolysis by adding 4 mL of 1 M HCl and 4 mL of 1 MNaOH, respectively. These mixtures were kept in a hot air oven for 48 h at 50 C and then reanalyzed by the green HPLC method for the determination of OLM in the presence of itsacid and base degradation products respectively.

The proposed RP-HPLC method is simple, selective, rapid,accurate, precise, reproducible, robust,

sensitive and stability indicating. Therefore, the method was applied to the assay ofOLM in SMEDDS

and commercial tablets. A high assay valuewas obtained in both of the formulations. The method is

alsosimple in terms of sensitivity, use of an environmentally benignmobile phase, lack of

extraction procedures, lower retentiontime (rapid analysis), no internal standard and UV detection.All these factors make this method superior for the

routineanalysis of OLM in bulk drugs and various commerciallyavailable formulations of OLM. The

method could also be appliedfor the prediction of shelf life in pharmaceutical formulationshaving OLM as an active ingredient because it is

havingstability-indicating properties. The replacement of widely-usedtraditional solvents and

chemicals with new, innocuous, andless toxic ones provides environmentally benign alternativesto the

more hazardous chemicals and processes in the fieldof drug/pharmaceutical analysis

• Armenta-TrendsinAnalChem-Vol27-2008

• green analytical chemistry_jacek namiesnik

•http//:mospace.umsystem.edu/../principles , TRAC 12 principles

• http//:www.essexpublishinggroup.com/

• from-the-colourless-to-the-green-analytical-chemistry-2157-

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