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                                                                   EXHIBIT 10.28
AmSouth(R)

     LIMITED SECURITY AGREEMENT                                        (Alabama)

     For value received. and to secure all of the Obligations as hereinafter
defined, the undersigned (hereinafter, whether one or more, collectively, the
"Obligor") hereby transfers, pledges and assigns to AmSouth Bank (hereinafter
called the "Bank") and grants and conveys to Bank security title to, a security
interest in, and a Lien upon, the following described property and assets
(hereinafter called the "Collateral"):

     (Complete as applicable)

     All investment property, financial assets, securities entitlements and all
other property of whatever nature, now or hereafter held in account number
###-##-#### maintained by the Obligor with AmSouth Investment Services, Inc.
including, without limitation, all securities, mutual fund shares, negotiable
instruments, bonds, certificates of deposit, warrants, options and general
intangibles (all terms used herein and defined in the Alabama Uniform Commercial
Code ("UCC") shall have the meanings given to them in the UCC) together with all
proceeds and avails thereof and all stock rights, rights to subscribe, dividends
and other distributions of every kind and description, stock splits, new
securities and certificates, substitutions, additions, replacements, renewals,
consolidations, modifications. interest and other rights or distributions which
are now or hereafter declared, issued, paid or payable with respect to an
account of such property and assets.

     The Obligor represents and warrants, and so long as this Limited Security
Agreement remains in effect shall be deemed continuously to represent and
warrant, that the Obligor is the owner of the Collateral free of all liens,
security interests or other encumbrances, other than the security interest
created by this Limited Security Agreement.

     "Obligation" or "Obligations" shall include all indebtedness, obligations
(including obligations of performance) and liabilities of any or all parties
named as Obligor to Bank of every kind and description whatsoever, direct or
indirect, absolute or contingent and due or to become due, now existing or
hereafter incurred, contracted or arising, or acquired by Bank from any source,
joint or several, liquidated or unliquidated, regardless of how they arise or by
what agreement or instrument they may be evidenced or whether they are evidenced
by any agreement or instrument, and whether incurred as maker, endorser, surety,
guarantor or otherwise, including without limitation obligations incurred in
connection with the issuance of a letter of credit, and any and all extensions
and renewals of any of the same.

     The Obligor agrees that any shares of stock received as a result of stock
dividends, stock splits or other such distributions with respect to the
Collateral shall be delivered to the Bank by the Obligor promptly upon receipt
by the Obligor.

     In case of depreciation in the market value of any item of the Collateral
or, if for any cause whatsoever the Collateral shall cease to be satisfactory to
Bank, such Obligor shall forthwith, upon demand of Bank deposit with Bank as
part of the Collateral additional property satisfactory to Bank. Such demand may
be made in person or by mail addressed to such Obligor at the address given
below, or if none is given, to any address of such Obligor in Bank's files.

     Bank shall have, but shall not be limited to, the following rights, each of
which may be exercised at any time without the necessity of notice to (except as
the same may be provided for elsewhere) or consent of any Obligor, but which
rights the Bank shall have no obligation, or liability for failure to exercise:

     (i)   Receive and take control of any proceeds of or income (other than
           cash dividends paid in the ordinary course prior to the occurrence of
           an Event of Default) on the Collateral, including money, and hold the
           same as Collateral, or apply the same to any one or more of the
           Obligations, the manner, order and extent of such application to be
           in the sole discretion of Bank;

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     (ii)  Substitute, release or surrender, deposit subject to any plan of
           reorganization, liquidate, demand, sue for, collect, compromise,
           settle or receive or receipt for the cash or surrender value of the
           Collateral; and

     (iii) Receive and take control of dividends (other than cash dividends
           received in the ordinary course prior to the occurrence of an Event
           of Default), other distributions (including stock redemption
           proceeds, or other securities in respect of or in exchange for or
           replacement of any of the Collateral), whether by way of dividends
           (other than cash dividends received in the ordinary course prior to
           the occurrence of an Event of Default), recapitalizations,
           conveyances of assets, liquidations, mergers, consolidations,
           stock-splits, spin-offs, split-ups, reclassifications, combinations
           or exchanges of shares or otherwise, such dividends, distributions or
           other securities, or certificates representing the same, to be
           thereafter treated in all respects as Collateral.

     Additions to, reductions or exchanges of, or substitutions for the
Collateral, and payments on account of the Obligations or any other
indebtednesses, obligations or liabilities incurred partially or wholly in
reliance upon the Collateral, may from time to time be made without affecting
the provisions hereof.

     Prior to the occurrence of an Event of Default, all cash dividends paid
with respect to the Collateral in the ordinary course may be retained by an
Obligor, provided that all cash dividends payable with respect to the Collateral
determined by Bank, in its absolute discretion, to represent in whole or in part
an extraordinary or liquidating dividend or distributions in return of capital
shall be paid to Bank and retained by it in a non-interest-bearing fund as
security for the Obligations, except as otherwise provided in the investment
agreement.

     Unless and until an Event of Default shall have occurred, each Obligor
shall have the right to vote any and all shares of any of the Collateral which
is comprised of voting securities pledged by such Obligor and to give consents,
waivers and ratifications with respect to any such Collateral and otherwise act
with respect thereto. All such rights of the Obligor to vote and to give
consents, waivers and ratifications shall, at the option of Bank, cease upon the
occurrence of an Event of Default.

     Bank shall be deemed to have exercised reasonable care in the custody and
preservation of the Collateral to the extent required by applicable law if it
takes such action for that purpose as any Obligor shall reasonably request in
writing; but no omission to do any act not requested by an Obligor shall be
deemed a failure to exercise reasonable care and no omission to comply with any
request of an Obligor shall of itself be deemed a failure to exercise reasonable
care. Each Obligor shall take all necessary steps to preserve rights against
prior parties to instruments or chattel paper constituting Collateral and shall
he responsible generally for its preservation, and Bank shall have no obligation
or responsibility therefor.

     Upon the happening of any one or more of the following events (herein
called, individually, an "Event of Default" and, collectively, "Events of
Default"), each of which shall constitute a default hereunder, all unpaid
amounts represented by all Obligations shall immediately become due and payable,
with interest to date (or if interest has been deducted therefrom or included
therein, with unearned interest credited), without demand or notice,
notwithstanding any other expressed maturities of any thereof, unless Bank shall
on notice of such event elect to waive in writing such acceleration: (a) Failure
of any Obligor to pay any of the Obligations, or any part thereof, when due; or
(b) Occurrence of any event of default under the provisions at any loan
agreement or other instrument or other document evidencing or securing or
executed in connection with any of the Obligations, or (c) Failure of any
Obligor to deposit additional Collateral upon demand; or (d) Failure of any
Obligor to perform any other agreement hereunder; or (e) Abandonment of any of
the Collateral by any Obligor; or (f) Occurrence of any default with respect to
borrowed indebtedness other than the Obligations now or hereafter owing by any
party liable for any part of the Obligations; or (g) Misrepresentations by any
Obligor of any material fact in any statement to Bank at any time; or
(h) Occurrence of any of the following events with respect to any Obligor: death
(if an individual) or dissolution (if a partnership or corporation); death or
suspension of the usual business activities of any partner of an Obligor that is
a partnership or of any principal officer of an Obligor which is a corporation;
imminent or threatened insolvency; insolvency; assignment for the benefit of
creditors; calling a meeting of any creditors, appointment of a committee of any
creditors or liquidating agent; offering to or receiving from any creditors a
composition, refinancing,

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restructuring or extension of any Obligor's indebtedness; making or sending
notice of an intended bulk transfer; suspension of payment; the whole or partial
suspension or liquidation of any usual business of any Obligor, failing, after
demand by Bank, to furnish any financial information or to permit inspection of
books or records of account; commencement of any proceeding, suit or action (at
law or in equity, or under any provisions of any federal or state bankruptcy law
or amendments thereto) for an order of relief, adjudication as a bankrupt, or
for reorganization, composition, extension, arrangement, wage earner's plan,
receivership, liquidation or dissolution by or against any Obligor; entry of a
judgment or issuance of a warrant of attachment, or an injunction against any
Obligor or against any property of any Obligor, issuance of an execution against
property of any Obligor or commencement against any Obligor of any proceeding
for enforcement of a money judgment; or (i) in the event Bank in good faith
deems itself insecure for any reason.

     If an Event of Default shall occur, Bank shall be entitled to exercise,
successively or concurrently, all of the rights, powers and remedies vested in
it by this Limited Security Agreement, and now or hereafter existing at law or
in equity or by statute (including without limitation the Uniform Commercial
Code of the state of Bank's principal place of business) or otherwise for the
protection and enforcement of its rights with respect to the Collateral; and
each Obligor hereby irrevocably appoints and constitutes Bank as such Obligor's
attorney-in-fact, coupled with an interest and with full power of substitution,
to exercise any or all the following rights, powers and remedies:

     (a)   to receive all cash dividends and other amounts payable with respect
           to the Collateral otherwise payable to such Obligor prior to the
           occurrence of an Event at Default;

     (b)   to endorse and transfer all or any part of the Collateral into Bank's
           name or the name of its nominee and to cause new certificates to be
           issued in the name of Bank or of such nominee.

     (c)   provided that Bank has given one (1) calendar day's notice in writing
           of its intent to exercise rights under this subparagraph to vote all
           or any part of the Collateral, whether or not transferred into the
           name of Bank, and to give all proxies, consents, waivers and
           ratifications with respect to the Collateral and otherwise act with
           respect thereto as though it were the outright owner thereof; and

     (d)   at any time or from time to time to sell, assign and deliver, or
           grant options to purchase, all or any part of the Collateral, or any
           interest therein, at any public or private sale, to the fullest
           extent permitted by law, without demand of performance, advertisement
           or notice of intention to sell or of the time or place of sale or
           adjournment thereof or other notice of any kind (all of which are
           hereby waived by each Obligor to the fullest extent permitted by
           law), for cash, on credit or for other property, for immediate or
           future delivery without any assumption of credit risk, and for such
           price or prices and on such terms as Bank in its absolute discretion
           may determine. Bank may, but shall not be obligated to, sell all or
           any portion of the Collateral through any broker now or hereafter
           affiliated with it, and such Obligor hereby consents to Bank's
           selling the same through any such broker.

     Each Obligor hereby waives and releases to the fullest extent permitted by
law any right or equity of redemption with respect to the Collateral, whether
before or after sale hereunder, and all rights, if any, of marshalling the
Collateral and any other security for the Obligations or otherwise. At any such
sale, unless prohibited by applicable law, Bank may bid for and purchase all or
any part of the Collateral free from any such right or equity of redemption.

     To the extent notice of any sale or other disposition of the Collateral is
required by law to be given to an Obligor, the requirement of reasonable notice
shall be met by sending such notice, by certified mail, postage prepaid to such
Obligor at the address of such Obligor as it appears on this Limited Security
Agreement or, if none appears, to any address of such Obligor in Bank's files,
at least 5 days before the time of sale or disposition. Each Obligor shall
remain liable to Bank for the payment of any deficiency with interest as
hereinabove provided. However, Bank shall not be obligated to resort to any
Collateral but, at its election, may proceed to enforce any of the Obligations
in default against each Obligor without waiver of any rights as to the
Collateral or any other security or as to any Obligor against whom Bank shall
not elect then to proceed.

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     All moneys collected upon any disposition of the Collateral hereunder,
together with all other moneys received from any source on account of all or any
portion of the Obligations, shall be first applied to the payment of all costs
and expenses incurred by Bank in connection with the disposition of the
Collateral or the collection of the Obligations (including, without limitation,
all attorneys' fees as herein provided) and then to the Obligations in such
order and manner as Bank shall consider appropriate.

     If at any time Bank shall determine to sell all or any of the Collateral
and the Collateral (or the part thereof to be sold) shall not be effectively
registered under the Securities Act at 1933, as then in effect, or any similar
federal or state law relating of the registration and sales of securities
("Securities Laws"), Bank may, in its sole discretion, sell the Collateral or
part thereof, through a private sale in such manner and under such circumstances
as Bank may deem necessary or advisable in order that such Collateral may be
lawfully sold without being registered under the Securities Laws. Without
limiting the generality of the foregoing, Bank, in its sole discretion, (a) may
proceed to sell the Collateral or any part thereof through a non-public sale,
whether or not a registration statement concerning such Collateral shall have
been filed under the Securities Laws, (b) may approach and negotiate with as few
as one possible purchaser, and (c) may restrict such sale to a purchaser who
will represent and agree that such purchaser is purchasing for its own account,
for investment, and not with a view to the distribution or sale of such
Collateral and who satisfies such other conditions as at that lime may be
required in order for Bank to conduct a lawful non-public sale of such
Collateral. In the event of any such non-public sale, Bank shall be authorized
to sell all or any part of the Collateral at a price that Bank, in its sole
discretion, deems reasonable under the circumstances, notwithstanding the
possibility that a higher price might be realized if the sale were deferred
until after registration under the Securities Laws.

     The obligations of each Obligor under this Agreement shall be absolute and
unconditional and shall remain in full force and effect without regard to, and
shall not be released, suspended, discharged, terminated or otherwise affected
by, any circumstance or occurrence whatsoever, including, without limitation (a)
any renewal, extension, amendment or modification of or addition or supplement
to this Limited Security Agreement or any note evidencing, or other instrument
or document executed in connection with, or as security for, the Obligations or
any part thereof (herein collectively called "Loan Documents"), or any
assignment or transfer thereof; (b) any waiver, consent, extension, indulgence
or other action or inaction under or with respect to the Loan Documents or any
exercise or non-exercise of any right, remedy, power or privilege under or with
respect to any Loan Document or this Limited Security Agreement; (c) any
furnishing of any additional security to Bank or any acceptance thereof or any
release of any security or guaranty by Bank; (d) any limitation on or release or
discharge of any party's liability or obligations under any Loan Document or the
validity of unenforceability, in whole or in part of any Loan Document or any
term thereof; or (e) any bankruptcy. insolvency, reorganization, composition,
adjustment, dissolution, liquidation or other like proceeding relating to any
Obligor, or any action taken with respect to this Limited Security Agreement by
any trustee or receiver or by any court, in any such proceeding; whether or not
any Obligor shall have notice or knowledge of any of the foregoing.

     Each Obligor: (a) as to all or any portion of the Obligations, consents to
Bank's releasing, agreeing not to sue, suspending the right to enforce any Loan
Document against, or otherwise discharging or compromising any of the
Obligations of, any Obligor or any other person against whom any Obligor has a
right of recourse and (b) consents to Bank's releasing, exchanging or otherwise
dealing in any manner with all or any portion of the Collateral and any other
collateral, lien or right of set-off which may now or hereafter secure the
Obligations, or any portion et the Obligations, even though such release,
exchange or other dealing may in any manner and to any extent impair any such
Collateral, other collateral, lien or right of set-off. And Bank may take any or
all of the actions mentioned in clauses (a) or (b) of this paragraph without
notice to or further reservations of rights against any Obligor and all without
in any way affecting or releasing the liability of any Obligor.

     Each Obligor hereby severally (a) waives demand, presentment, protest,
notice of protest, notice of dishonor, suit against any party and all other
requirements necessary to hold such Obligor; (b) agrees to pay all costs of
collecting or securing or attempting to collect or secure the Obligations or
defending any unsuccessful claim asserted against Bank in connection with this
Limited Security Agreement or the Obligations or any portion thereof, including
reasonable attorneys' fees, provided, however, that if this Limited Security
Agreement is subject to Section 5-19-10 of the Code of Alabama 1975, attorney's
fees shall be limited to 15% of the unpaid balance of the Obligations after
default and referral to an attorney that is not a salaried employee of Bank, and
no attorneys' fees shall be payable if the original amount financed does not
exceed $300.00.

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     Each Obligor will, from time to time, on request by Bank, execute such
other or further transfers, instruments, proxies, consents or powers of attorney
as may be requested by Bank with respect to the Collateral.

     No failure or delay on the part of Bank in exercising any right, power or
privilege under this Limited Security Agreement shall operate as a waiver
thereof, nor shall a single or partial exercise thereof preclude any other or
further exercise or the exercise of any other right, power or privilege. No
modification, amendment, or waiver of any provision of this Limited Security
Agreement shall be effective unless in writing and signed by a duly authorized
officer of Bank, and then the same shall be effective only in the specific
instance and for the purpose for which given. No notice to or demand on any
Obligor in any case shall entitle any Obligor to any other or further notice or
demand in the same, similar or other circumstances.

     Any provision of this Limited Security Agreement that is prohibited or
unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective
to the extent of such prohibition or unenforceability without invalidating the
remaining provisions hereof or affecting the validity or enforceability of such
provision in any other jurisdiction.

     All rights, powers. and remedies of Bank under this Limited Security
Agreement and now or hereafter existing at law, in equity or otherwise shall be
cumulative and may be exercised successively or concurrently.

     This Limited Security Agreement shall be construed in accordance with and
governed by the laws of the State of Alabama. This Limited Security Agreement
shall remain in full force and effect until a written instrument of termination
shall he executed and delivered by a duly authorized officer of Bank. Each
Obligor agrees that this Limited Security Agreement shall secure all Obligations
(as defined herein), whether now existing or hereafter incurred, contracted for
or arising. Payment in full of the Obligations outstanding at any one time shall
not, in the absence of the execution and delivery of a written instrument of
termination as aforesaid, terminate this Limited Security Agreement.

     Each Obligor has subscribed his name hereto without condition that anyone
else should sign or become bound hereon and without any other condition whatever
being made. The provisions hereof are binding upon the heirs, executors,
administrators, assigns and successors of each Obligor, and shall inure to the
benefit of the Bank, its successors and assigns. All liabilities of the parties
named as "Obligor" hereunder are joint and several.

     This agreement is executed under the seal of each Obligor.

CAUTION - IT IS IMPORTANT THAT YOU THOROUGHLY READ THIS CONTRACT BEFORE YOU
SIGN IT.

     Dated: May 31, 2000                Surgical Laser Technologies, Inc.

                                        By: /s/ Michael R. Stewart (seal)
                                        Its: President & CEO

     Witnesses as to
     all signatures:

                                        By: /s/ Davis Woodward (seal)
     /s/ Craig K. Carra                 Its: VP, Finance, CFO

                                        Address: 147 Keystone Drive
                                        Montgomeryville, PA 18936