1. Sampling Protocol Sample needs to be representative of the body of water (or other matrix) from where it originates. Sampling Considerations A. Location B. Frequency (hourly, daily) C. Spatial and temporal considerations D. Matrix E. Safety Issues F. Filtered -vs- Non Filtered Automated vs- Grab Samples In Situ Instrumentation 1 Month Discharge (m 3 s -1 ) Alkalinity (meq L -1 ) Calcium (meq L -1 ) ph Conductivity ( S) EpCO 2 Temp. ( o C) Sunlight (h day -1 ) FRP ( M) TP ( M) January 7.14 3.94 4.79 8.03 524 6.40 5.05 1.78 4.38 7.38 February 6.48 3.95 4.82 8.00 518 6.88 5.50 2.65 4.04 6.88 March 4.69 4.12 4.94 8.04 530 6.55 7.74 4.02 3.44 5.97 April 4.82 3.98 4.81 8.07 518 5.94 9.24 5.59 2.87 5.54 May 5.07 4.09 4.86 8.08 515 5.93 12.28 6.97 3.38 6.22 June 5.24 4.09 4.77 8.08 520 5.92 15.25 6.64 4.67 8.23 July 5.42 4.12 4.86 8.06 515 6.59 18.05 7.36 5.34 7.88 August 6.47 4.14 4.93 8.02 521 6.98 18.15 7.06 5.47 8.87 September 7.09 4.00 4.75 7.96 518 7.85 14.24 4.60 5.70 9.40 October 6.78 3.90 4.73 7.84 516 9.51 11.06 3.99 5.70 8.44 November 6.64 3.75 4.61 7.85 510 9.4 7.66 2.31 4.89 7.88 December 6.78 3.85 4.59 7.9 506 8.4 4.78 1.78 4.36 8.29 2
160 Discharge Rainfall 140 8 Rainfall (mm) 120 100 80 Discharge (m 3 s -1 ) 6 60 4 40 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month 3 [FRP] μm) ( 5.30 5.25 5.20 5.15 5.10 5.05 5.00 4.95 4.90 4.85 FRP Discharge 3.20 3.15 3.10 3.05 3.00 2.95 2.90 2.85 Discharge (m 3 s -1 ) 4.80 21:30 01:30 07:00 12:30 17:00 00:30 05:30 12:00 16:30 23:00 Day 1 Day 2 Day 3 Time 2.80 4
12 11 10 TP [um] 9 8 Jan 7.36196 Feb 6.87762 Mar 5.68292 Apr 5.65063 May 6.19955 Jun 8.23377 Jul 8.00775 Aug 8.84727 Sep 9.78366 Oct 8.42751 Nov 8.04004 Dec 8.26606 7 6 5 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month 5 1. Sampling Protocol A. Cleaning Procedure (Paper Handout Read!) What issues are we concerned with? 1) Biological activity 2) Sample container composition 3) Breakdown of organic compounds B. Sample Collection 1) Simple and avoid contamination or interferences 2) Grab samples -vs- automatic samples 3) Sample bottles rinsed with sample (3x) 4) Collected halfway between surface + sediment Why? 6
C. Filtration differentiation between dissolved + particulate portions - Dissolved = that portion which passes through a 0.45 m filter. - High solids can cause interference (e.g. optical spectroscopy) - Also removes bacteria and plankton may release nutrients when cell ruptures 0.20 m filter 7 D. Sample Storage + Preservation 8
D. Sample Storage and Preservation 1) Chemical Methods a) Acidification (e.g. trace metals) why acidify? b) Chloroform (0.1%) prevents biological growth c) Mercuric chloride prevents biological growth 2) Physical Methods a) Refrigeration (4 C) b) Freezing (-20 C) c) Deep freezing (-80 C) Problems associated with freezing? 9 D. Sample Storage and Preservation - The effectiveness of the preservation method depends on: 1) Matrix 2) Filtration technique 3) Container type and size 4) Temperature 5) Type of chemical addition 6) Biological activity Note: Very matrix specific 10
11 F R P 4 o C + Chloroform 4 o C - 2 o 0C - 8 o 0C ( A) ( B ) ( C ) (D) 4 3 R i v e r F r o m e 2 1 0 (E) (F) (G) (H) 3 T a m a r 2 0.5 1 0 (I) (J) (K ) (L) 2 T a m a r 10 1 0 (M) 2 T a m a r 34 1 (N) (O) (P) 0 0 50 100 150 200 250 0 50 100 150 200 250 0 50 100 150 200 250 0 30 60 90 DAYS 12
E. Extraction Methods (Solid + Liquid) used to remove or isolate analytes or compounds of interest for analysis. 1) Liquid-Liquid (separatory funnel + toxic organic solvents) 2) Solid Phase Extraction uses a a solid + liquid phase to isolate analytes from solution 13 14
3) Liquid phase microextraction (LPME) smaller sample volumes sample extracted from an aqueous sample (1-5 ml volume) through a porous hollow fiber into a micro liquid-phase acceptor solution 4) Supercritical Fluid Extraction Fluid is neither a gas or a liquid but intermediate. only one phase exists Advantages 1. Non toxic solvents 2. Higher degree of separation 3. Cheaper in long run Disadvantages 1. High initial cost 2. Elevated pressure required http://sunny.vemt.bme.hu 15 5) Sample Preparation for Trace Metal Analysis Sample Preparation: a) Filtering b) Sieving / Grinding Dissolution or extraction of analyte Concentration is too dilute Measurement by AA, IPC, ICP-MS,IC 16
17 Wet Digestion Methods 1) Water Soluble Salts 2) Dilute Acids Easily oxidized metals and alloys, salts 3) Concentrated Acids Less oxidized metals, steels, metal oxides 4) Concentrated Acids w/ oxidizing agent metals, alloys, soils, particulates S. Mitra (Ed.) Sample Preparation Techniques in Analytical Chemistry (2003), Wiley-Interscience 18
Ex: Water Samples Filtration Acid Treatment ph 2-3 Storage at 4 C Analysis 19 Ex: Sample Preparation in DNA Analysis a) Chemical Properties S. Mitra (Ed.) Sample Preparation Techniques in Analytical Chemistry (2003), Wiley-Interscience 20
DNA Analysis: a) Polymerase Chain Reaction (PCR) method for amplifying DNA from a small amount of DNA catalyzed by DNA polymerase w/ a pair of primers (oligonucleotides). 21 S. Mitra (Ed.) Sample Preparation Techniques in Analytical Chemistry (2003), Wiley-Interscience Handout: Storage of Nutrients 1. What cleaning procedures are needed? 2. What parameters must be considered in any cleaning protocol? 3. What containers are the best? 4. What were the best storage conditions? 5. How does time affect concentration levels for each nutrient? 22