Device to apply a coating on tissue

samples for MALDI imaging

Holly LiskeLaura PiechuraKellen SheedyJenna Spaeth

Amy Harms, PhDUW Biotechnology Center

Brenda Ogle, PhDDepartment of Biomedical Engineering

Presentation Overview

Background of MALDI imaging Project motivation Problem statement Design criteria Design matrices Final design Budget evaluation Future work

MALDI-MSI

www.mc.vanderbilt.edu

Data Acquisition from MALDI-MSI

Alanine, neuropeptide in crab brain m/z = 1474.6

Valine, m/z = 1502.7

Alanine

Valine

Greg Barrett-Wilt, PhD., UW Biotechnology Center

Benefits of MALDI-MSI Analysis of entire

sample in one reading

Previous knowledge of molecular composition is not necessary

Allows for investigation of disease formation, progression, and treatment

www.maldi-msi.org

Matrix Application

Matrix application is vital for quality image resolution

Must contact sample as fine, liquid mist

Current procedure involves manual application with airbrush

100µm raster step

Greg Barrett-Wilt, PhD., UW Biotechnology Center

Problem Statement

Sample preparation methods MALDI-MSI are difficult to control

Requires accuracy and precision

A device to apply a fine, uniform coating of light-absorbing compounds

Project Motivation Objective 1:

Simplify matrix application, facilitate MALDI

Objective 2: Centralize a reliable

tool at UW Biotechnology Center

Implications for campus-wide, even global, research

www.buswire.ocr.wisc.edu

Design Criteria

Spray an even coating of matrix over an 81cm x 123 cm tissue sample

Adjustable spray aperture, air pressure and positioning of the plate and sprayer

Enclosed in a casing and operable within a fume hood

Design Matrix Adjustment

Several variables controlled by many independent components

Sprayer Method of application Enclosure Orientation

Created a component matrix to decide final design

Component Matrix

VerticalHorizontalOrientation

Detached covering

Integrated covering

Fume hoodEnclosure

Stationary sprayer,Movable

plate

Movable sprayer,

Stationary plate

Method of Application

Produce irrigation system

Pneumatic sprayer

Nebulizer

Nozzle-valve with pressure vessel

Automatic Spray Gun Sprayer

Ideas Feature

Criteria for ranking

Reliability Adjustability User interaction Cost Maintenance Ease of manufacture

Ranking System (1-5), highest = best

Mega MatrixSpraying Component

2.354.104.303.452.251.00Total

214310.05Ease of

Manufacture

243310.10Maintenance

315340.15Cost

354450.20User

Interaction

255410.25Adjustability

254310.25Reliability

Produce irrigation system

Pneumatic sprayer

Automatic Spray Gun

Nozzle-valve and

pressure vessel

NebulizerRankCriteria

Mega MatrixMethod of Application

3.252.851.00Total

130.05

Ease ofManufacture

330.10Maintenance

420.15Cost

430.20

User Interaction

330.25Adjustability

330.25

Reliability

Movable Plate Stationary Sprayer

Stationary Plate Movable Sprayer

RankCriteria

Mega MatrixEnclosure

2.452.91.551.00Total

4350.05Ease of

Manufacture

5410.10

Maintenance

3250.15

Cost

4410.20User

Interaction

2510.25

Adjustability

---0.25Reliability

Removable CoverIntegrated CoverFume HoodRankCriteria

Mega MatrixOrientation

1.25.51.00Total

--0.05Ease of

Manufacture

--0.10Maintenance

--0.15Cost

--0.20User

Interaction

--0.25

Adjustability

520.25

Reliability

Vertical SprayHorizontal

SprayRankCriteria

Final Design Model

1. Automatic Spray Gun

2. Conveyor

3. DC Timing Motor

4. Integrated Polyethylene Box

14

3

2

Budget Evaluation

$300.00 budget limit Breakdown

Air Spray Gun: $150.00 Motor/Conveyor: $45.00 Enclosure material: $45.00 Other small parts: $40.00

Total Estimate: $280.00 (under budget)

Future Work

Final Design modifications Order materials Build prototype Test in client’s lab

References Ashcroft, Alison. University of Leeds Astbury Centre for Structural

Molecular Biology. “An Introduction to Mass Spectrometry.” <http://www.astbury.leeds.ac.uk/>

Barrett-Wilt, Greg. University of Wisconsin Biotechnology Center. Personal interviews.

Caprioli Research Laboratory Center. Vanderbilt Medical Center.

<http://www.mcvanderbilt.edu> Khatib-Shahidi, Sheerin. “Direct Molecular Analysis of Whole-Body

Animal Tissue Section by Imaging MALDI Mass Spectrometry.” Analytical Chemistry. 2006, 78(18) 6448-6456.

Sugiura, Yuki. “Two-Step Matrix Application Technique to Improve Ionization Efficiency for MALDI-MSI.” Analytical Chemistry. 2006, 78(24) 8227-8235.

Any Questions?