A Microcontroller Operated Device for the Generation of Liquid Extracts from Conventional Cigarette Smoke and Electronic Cigarette Aerosol

Summary

Here, we describe a programmable laboratory device that can be used to create extracts of conventional cigarette smoke and electronic cigarette aerosol. This method provides a useful tool for making direct comparisons between conventional cigarettes and electronic cigarettes, and is an accessible entry point into electronic cigarette research.

Abstract

Electronic cigarettes are the most popular tobacco product among middle and high schoolers and are the most popular alternative tobacco product among adults. High quality, reproducible research on the consequences of electronic cigarette use is essential for understanding emerging public health concerns and crafting evidence based regulatory policy. While a growing number of papers discuss electronic cigarettes, there is little consistency in methods across groups and very little consensus on results. Here, we describe a programmable laboratory device that can be used to create extracts of conventional cigarette smoke and electronic cigarette aerosol. This protocol details instructions for the assembly and operation of said device, and demonstrates the use of the generated extract in two sample applications: an in vitro cell viability assay and gas-chromatography mass-spectrometry. This method provides a tool for making direct comparisons between conventional cigarettes and electronic cigarettes, and is an accessible entry point into electronic cigarette research.

Introduction

Despite a concentrated effort by health organizations, tobacco product use remains the leading cause of preventable death worldwide, with the majority of these deaths attributed to cigarette smoking¹. Since entering the market in 2003, electronic cigarettes have been growing in popularity among tobacco product users. Currently, electronic cigarettes are the most popular alternative to conventional cigarettes among American adults (~5%)² and the most popular nicotine delivery system among middle (~5.3%) and high schoolers (~16%)³. If current trends continue, electronic cigarettes can be expected to....

Protocol

1. Assembly of the Device

1. Secure a 100 mL Buchner flask (Figure 1, #4) to a steel ring stand and create a vacuum trap by filling it with 50 g of calcium chloride to serve as a desiccant. Seal the flask with a rubber through-hole stopper, wrap the stopper junction with paraffin film, and run a pipette through the hole.
2. Using vinyl tubing, connect the pipette extending from the stopper to a t-intersection hose connector.
3. Using vinyl tubing, connect the two impinger (Figure 1, #2 & #3) to each other and connect the output of the second impinger to the t-intersection hose connector....

Results

Within 24 hours of the exposure of human umbilical vein endothelial cells to either conventional cigarette smoke extract (CSE) or electronic cigarette aerosol extract (EAE), there is a significant (control vs. CSE P <0.001; control vs. EAE P <0.01; n = 6) reduction in cell viability (Figure 3A). Extracts were generated with a puffing profile of 2, 2 second, 55 mL puffs per minute and normalized based on molar concentration of nicotine .......

Discussion

The most critical elements of this protocol are ensuring the device is clean at the start and finish of each extraction, and ensuring that all seals are maintained so that air flow remains consistent. If the device is not properly cleaned, there is a risk of carry over between samples. Additionally, if the device is left unclean for an extended period of time condensed aerosol and dried solvent can block the system. Note that it is normal for there to be a pressure drop when puffing a conventional cigarette and the airfl.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
12 V AC/DC Wall Mount Adaptor	Digi-Key	T1099-P5P-ND
2.2 Ohm Resistors	Digi-Key	A105635-ND	Used in tandem to generate the 4.4 Ohm resistance in Figure 2A
330 Ohm Resistors	Digi-Key	330QBK-ND
510 Threaded Base	NJoy	N/A	Recovered by dismantalling a second generation NJoy electronic cigarette
Acetic Acid, Glacial	Sigma-Aldritch	A6283
Acetone (Chromatography Grade)	Sigma-Aldritch	34850
Basic Stamp Project Board	Digi-Key	27112-ND	This board contains the BS1 Microcontroller, serial adaptor, power switch, and a barrel pin connector for the AC/DC Wall Mount Adaptor
Basic Stamp USB to Serial Adapter	Digi-Key	28030-ND	An optional component to allow the BS1 serial adaptor to communicate through USB
Buchner Flask (Vacuum Flask) 250 mL	VWR	10545-854
Clear Tape	3M	S-9783
Clear Vinyl Tubing, 3/8" ID	Watts	443064
EGM-2 Endothelial Cell Culture Medium	Lonza	CC-3162
Ethanol	Pharmco-Aaper	111000200
Flow Regulator	Dwyer	VFA-23-BV
Gas Chromatograph	Varian	450-GC
Glass Syringe, 10 mL	Sigma-Aldritch	Z314552
Glass Syringe, 10 µL	Hamilton	80300
High Vacuum Silicon Grease	Dow Corning	146355D
Hose Clamp	Precision Brand	35125
Human Umbilical Vein Endothelial Cells	ATCC	PCS-100-013
Mass Spectrometer	Varian	300-MS
Midget Impinger	Chemglass	CG-1820-01
Neutral Red	Sigma-Aldritch	N4638
Paraffin Film	3M	PM-992
Plate Seal Roller	BioRad	MSR0001
Plate Seal; Foil	Thermo	276014
Ring Stand 20"	American Educational Products	7-G15-A
Solenoid Valve (normally open)	US Solid	USS2-00081
Solid State Relay	Digi-Key	CLA279-ND
Stand Clamp	Eisco	CH0688
Syringe Filter, PES, 0.22 um	Millipore	SLGP033RS
Syringe, 10 mL	BD Syringe	309604
Through Hole Stopper, Size 6	VWR	59581-287
Vacuum Pump	KNF Neuberger	N86KTP