Electrospray in the dripping mode for cell microencapsulation

Jingwei Xie, Chi Hwa Wang

Research output: Contribution to journalArticle

88 Citations (Scopus)

Abstract

Entrapment of living cells in microbeads is to protect the encapsulated cells from the host's immune system, which can be used as drug delivery vehicles, immunotherapies and engineered tissues. The main objective of the present study was to investigate the droplet formation and to better develop mono-dispersed microencapsulation of living cells with controllable size. The uniformity of microencapsulation size was realized by performing electrospray in the dripping mode and also stabilized by an additional ring electrode. Reduction of droplet diameter and increase in the dripping frequency were observed with increasing applied voltage to the nozzle using a conventional electrospray setup. The vibration of the needle was found to reduce when high voltage was applied to the nozzle. With increasing voltage applied to the ring electrode, the dripping frequency was found to decrease with the formation of slightly larger sizes of droplets. Hep G2 cell line was taken as the model cell line for encapsulation in calcium alginate microbeads. Relatively uniform microbeads could be achieved when operating under low flow rates with high voltages applied to the nozzle by using a conventional electrospray setup. In contrast, uniform microbeads can not be obtained using a similar setup under high flow rates unless the ring electrode is applied with voltage to stabilize the electrospray in the dripping mode. In this modified electrospray, microbeads with narrow size distribution and slightly larger size can be obtained even for cases under high flow rates. Phase contrast microscope images showed that the diameter of microbeads from around 200 μm to 2 mm could be finely tuned by adjusting various operating parameters.

Original languageEnglish (US)
Pages (from-to)247-255
Number of pages9
JournalJournal of Colloid and Interface Science
Volume312
Issue number2
DOIs
StatePublished - Aug 15 2007

Fingerprint

Microencapsulation
nozzles
Cells
flow velocity
Electric potential
Nozzles
cells
cultured cells
electrodes
Flow rate
high voltages
rings
electric potential
Electrodes
immune systems
entrapment
phase contrast
needles
Immune system
Alginate

Keywords

  • Dripping
  • Droplet formation
  • Electrospray
  • Microencapsulation

ASJC Scopus subject areas

  • Colloid and Surface Chemistry
  • Physical and Theoretical Chemistry
  • Surfaces and Interfaces

Cite this

Electrospray in the dripping mode for cell microencapsulation. / Xie, Jingwei; Wang, Chi Hwa.

In: Journal of Colloid and Interface Science, Vol. 312, No. 2, 15.08.2007, p. 247-255.

Research output: Contribution to journalArticle

@article{a75a1982537b4fe5a00885d0f76a576d,
title = "Electrospray in the dripping mode for cell microencapsulation",
abstract = "Entrapment of living cells in microbeads is to protect the encapsulated cells from the host's immune system, which can be used as drug delivery vehicles, immunotherapies and engineered tissues. The main objective of the present study was to investigate the droplet formation and to better develop mono-dispersed microencapsulation of living cells with controllable size. The uniformity of microencapsulation size was realized by performing electrospray in the dripping mode and also stabilized by an additional ring electrode. Reduction of droplet diameter and increase in the dripping frequency were observed with increasing applied voltage to the nozzle using a conventional electrospray setup. The vibration of the needle was found to reduce when high voltage was applied to the nozzle. With increasing voltage applied to the ring electrode, the dripping frequency was found to decrease with the formation of slightly larger sizes of droplets. Hep G2 cell line was taken as the model cell line for encapsulation in calcium alginate microbeads. Relatively uniform microbeads could be achieved when operating under low flow rates with high voltages applied to the nozzle by using a conventional electrospray setup. In contrast, uniform microbeads can not be obtained using a similar setup under high flow rates unless the ring electrode is applied with voltage to stabilize the electrospray in the dripping mode. In this modified electrospray, microbeads with narrow size distribution and slightly larger size can be obtained even for cases under high flow rates. Phase contrast microscope images showed that the diameter of microbeads from around 200 μm to 2 mm could be finely tuned by adjusting various operating parameters.",
keywords = "Dripping, Droplet formation, Electrospray, Microencapsulation",
author = "Jingwei Xie and Wang, {Chi Hwa}",
year = "2007",
month = "8",
day = "15",
doi = "10.1016/j.jcis.2007.04.023",
language = "English (US)",
volume = "312",
pages = "247--255",
journal = "Journal of Colloid and Interface Science",
issn = "0021-9797",
publisher = "Academic Press Inc.",
number = "2",

}

TY - JOUR

T1 - Electrospray in the dripping mode for cell microencapsulation

AU - Xie, Jingwei

AU - Wang, Chi Hwa

PY - 2007/8/15

Y1 - 2007/8/15

N2 - Entrapment of living cells in microbeads is to protect the encapsulated cells from the host's immune system, which can be used as drug delivery vehicles, immunotherapies and engineered tissues. The main objective of the present study was to investigate the droplet formation and to better develop mono-dispersed microencapsulation of living cells with controllable size. The uniformity of microencapsulation size was realized by performing electrospray in the dripping mode and also stabilized by an additional ring electrode. Reduction of droplet diameter and increase in the dripping frequency were observed with increasing applied voltage to the nozzle using a conventional electrospray setup. The vibration of the needle was found to reduce when high voltage was applied to the nozzle. With increasing voltage applied to the ring electrode, the dripping frequency was found to decrease with the formation of slightly larger sizes of droplets. Hep G2 cell line was taken as the model cell line for encapsulation in calcium alginate microbeads. Relatively uniform microbeads could be achieved when operating under low flow rates with high voltages applied to the nozzle by using a conventional electrospray setup. In contrast, uniform microbeads can not be obtained using a similar setup under high flow rates unless the ring electrode is applied with voltage to stabilize the electrospray in the dripping mode. In this modified electrospray, microbeads with narrow size distribution and slightly larger size can be obtained even for cases under high flow rates. Phase contrast microscope images showed that the diameter of microbeads from around 200 μm to 2 mm could be finely tuned by adjusting various operating parameters.

AB - Entrapment of living cells in microbeads is to protect the encapsulated cells from the host's immune system, which can be used as drug delivery vehicles, immunotherapies and engineered tissues. The main objective of the present study was to investigate the droplet formation and to better develop mono-dispersed microencapsulation of living cells with controllable size. The uniformity of microencapsulation size was realized by performing electrospray in the dripping mode and also stabilized by an additional ring electrode. Reduction of droplet diameter and increase in the dripping frequency were observed with increasing applied voltage to the nozzle using a conventional electrospray setup. The vibration of the needle was found to reduce when high voltage was applied to the nozzle. With increasing voltage applied to the ring electrode, the dripping frequency was found to decrease with the formation of slightly larger sizes of droplets. Hep G2 cell line was taken as the model cell line for encapsulation in calcium alginate microbeads. Relatively uniform microbeads could be achieved when operating under low flow rates with high voltages applied to the nozzle by using a conventional electrospray setup. In contrast, uniform microbeads can not be obtained using a similar setup under high flow rates unless the ring electrode is applied with voltage to stabilize the electrospray in the dripping mode. In this modified electrospray, microbeads with narrow size distribution and slightly larger size can be obtained even for cases under high flow rates. Phase contrast microscope images showed that the diameter of microbeads from around 200 μm to 2 mm could be finely tuned by adjusting various operating parameters.

KW - Dripping

KW - Droplet formation

KW - Electrospray

KW - Microencapsulation

UR - http://www.scopus.com/inward/record.url?scp=34250622461&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34250622461&partnerID=8YFLogxK

U2 - 10.1016/j.jcis.2007.04.023

DO - 10.1016/j.jcis.2007.04.023

M3 - Article

VL - 312

SP - 247

EP - 255

JO - Journal of Colloid and Interface Science

JF - Journal of Colloid and Interface Science

SN - 0021-9797

IS - 2

ER -