ISSN 1070-4272, Russian Journal of Applied Chemistry, 2014, Vol. 87, No. 8, pp. 1146−1150. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © Yu.A. Nashchekina, I.M. Zorin, P.A. Fetin, S.Ya. Skachilova, A.Yu. Bilibin, 2014, published in Zhurnal Prikladnoi Khimii, 2014, Vol. 87,
No. 8, pp. 1167−1171.
AND POLYMERIC MATERIALS
Composite Film Materials Based
) and Acexamic Acid
Yu. A. Nashchekina
, I. M. Zorin
, P. A. Fetin
, S. Ya. Skachilova
, and A. Yu. Bilibin
Institute of Chemistry, St. Petersburg State University, Universitetskaya nab. 7–9, St. Petersburg, 199034 Russia
Institute of Cytology, Russian Academy of Sciences, Tikhoretskii pr. 4, St. Petersburg, 194064 Russia
All-Russia Scientiﬁ c Center for Safety of Biologically Active Compounds,
ul. Kirova 23, Staraya Kupavna, Moscow oblast, 142450 Russia
Received July 22, 2014
Abstract—The inﬂ uence of the hydrophilicity and molecular mass of poly(D,L-lactide) on the solubility of
acexamic acid in the polylactide ﬁ lm and on the rate of its release from the polymer was studied. The release of
acexamic acid from the polylactide ﬁ lm is described by a two-step model according to which the ﬁ rst step consists
in dissolution of acexamic acid occurring in the intrinsic crystalline phase, and the second step, in the release
of acexamic acid dissolved in the poly(D,L-lactide) phase. The results of conductometric measurements show
that the limiting solubility of acexamic acid in poly(D,L-lactide) is higher in more hydrophilic ﬁ lms prepared
using zinc lactate and amounts to 5–8%. The rate of the acexamic acid release increases with a decrease in the
molecular mass of poly(D,L-lactide).
For quick and efﬁ cient wound healing, it is necessary
that a drug should be present in the wound for a deﬁ nite
time . Many drugs used for treatment of wounds and
burns exert curative effect at low concentrations but cause
side effect at high concentrations . Therefore, wound-
healing coatings consisting of a polymeric matrix and a
drug released at controllable rate onto the wound surface
have found wide use in the modern medical practice .
The rate at which small doses of a drug are released into a
living body can be controlled by varying the properties of
the matrix, which allows the toxicity of the drug, caused
by its increased dosage when it is applied at once, to be
reduced. Also, an important advantage of using a wound-
healing coating is that the extent of injuring the wound
is reduced compared to common treatment with daily
dressing for application of a drug onto the wound surface.
6-(N-Acetylamino)hexanoic acid (acexamic acid, AA)
is one of effective drugs actively used for curing burns
and wounds. Acexamic acid as a component of ointments
and solutions accelerates the removal of necrotic
masses from the wound surface, decreases exudation,
activates the granulation tissue growth, accelerates the
vascularization and regeneration of tissues, and prevents
the formation of keloid scars . However, the use of AA
as a component of ointments or solutions requires daily
dressing. Application of AA onto the wound surface by
desorption from a wound coating will allow not only the
frequent mechanical damage of wounds in the course
of dressing to be avoided, but also the dosage of the
introduced drug to be controlled.
A polymer based on lactic acid, poly(D,L-lactide)
(PL), is one of promising biodegradable polymeric
materials used, in particular, as matrices for wound-
healing coatings .
It is known that the hydrophilicity of the synthesized
poly(D,L-lactide) is inﬂ uenced by the kind of the initiator
. For example, poly(D,L-lactide) synthesized in the
presence of zinc lactate is more hydrophilic than the
polymer synthesized in the presence of tin octanoate .
The goals of this study are the development of a
wound-healing coating based on a polylactide matrix